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Article

The Effect of Co-Administration of Levetiracetam or Brivaracetam with Ethanol on the Associative Learning and Anxiety Level of Rats

by
Ewa Zwierzyńska
and
Bogusława Pietrzak
*
Department of Pharmacodynamics, Medical University of Lodz, Muszyńskiego 1, 90-151 Łódź, Poland
*
Author to whom correspondence should be addressed.
Future Pharmacol. 2025, 5(3), 45; https://doi.org/10.3390/futurepharmacol5030045
Submission received: 26 June 2025 / Revised: 21 July 2025 / Accepted: 5 August 2025 / Published: 21 August 2025

Abstract

Background: Ethanol intake leads to cognitive deficits. Recent research demonstrated that a dysregulation of synaptic vesicle glycoprotein 2A (SV2A) expression seems to be linked to anxiety and memory disorders. Levetiracetam and brivaracetam are two antiseizure drugs that affect the SV2A protein. This study aimed to assess the impact of these drugs on associative learning and anxiety-like behaviors in ethanol-treated rats. Methods: Adult male Wistar rats (n = 64) were given brivaracetam or levetiracetam via i.g. for three weeks at doses of 300 mg/kg or 6 mg/kg, respectively. Ethanol was administered as a 20% solution twice a day, via i.g., at a morning dose of 1.5 g/kg b.w. and an afternoon dose of 3.5 g/kg b.w. Additionally, 5% ethanol was available ad libitum between 4:00 p.m. and 8:00 a.m. Associative learning was evaluated using the passive avoidance test during the alcohol administration period, as well as the contextual fear conditioning and cued fear conditioning tests during the withdrawal period. The level of anxiety was determined using the elevated plus maze test in withdrawal rats. Results: Ethanol consumption resulted in impaired associative memory, and its withdrawal was linked to increased anxiety levels. Levetiracetam enhanced memory performance in the passive avoidance test, but brivaracetam disturbed memory associated with unpleasant stimuli in the contextual fear conditioning. Additionally, withdrawal-induced disturbance of locomotor activity persisted, particularly in animals receiving levetiracetam in the elevated plus maze. Conclusions: Levetiracetam appears to provide certain beneficial effects, whereas brivaracetam may worsen memory disturbances in rats.

Graphical Abstract

1. Introduction

Excessive alcohol consumption is associated with severe health problems, including neurological disorders. Ethanol is recognized as a neurotoxin that directly impacts nerve cells, contributing to various cognitive deficits. Its intake may lead to memory loss due to ethanol-induced neuroadaptations in memory-related brain regions. The key brain structure associated with memory consolidation is the hippocampus [1,2]. It has been shown that alcohol impairs the function of the hippocampus by disrupting neurotransmitter release and synaptic plasticity. Moreover, ethanol also increases the production of reactive oxygen species and inflammatory molecules [3]. The amygdala, which is closely connected to the hippocampus, is involved in anxiety and mood regulation. This structure plays a key role in fear memory acquisition and storage and is involved in fear conditioning tests [4]. Similarly to the hippocampus, alcohol can also disrupt synaptic transmission in the amygdala, leading to the suppression of fear conditioning and emotional memory dysregulation, both during chronic exposure and withdrawal [1]. It is known that alcohol withdrawal is associated with anxiety symptoms, which may lead to a relapse to ethanol abuse [5].
The synaptic vesicle glycoprotein 2 (SV2) family comprises three transmembrane proteins, with SV2A being the most expressed in the brain. Although the function of the SV2A protein remains unclear, it plays a role in modulating neurotransmitter release. It binds synaptotagmin and regulates its trafficking and expression [6]. The SV2A protein is found in both GABAergic and glutamatergic terminals within the hippocampus, and it might contribute to achieving the balance between excitatory and inhibitory signals [7]. It is known that ethanol may interfere with the activity of these neurotransmissions [1]. Drugs that primarily affect the SV2A protein include levetiracetam and brivaracetam. However, they interact with the protein differently [8]. Moreover, levetiracetam inhibits the high-voltage-activated calcium channels [9] and affects both GABAergic and glutamatergic neurotransmissions [10,11]. This impact may not be direct but could be related to the SV2A protein [12] or calcium channels [13]. Brivaracetam may exhibit similar effects induced by SV2A [12]. Recent research has demonstrated that a dysregulation of hippocampal SV2A expression is linked to anxiety and memory disorders [14]. A reduction in SV2A binding has also been observed in patients with Alzheimer’s disease [15]. Preclinical studies indicate that levetiracetam and brivaracetam have beneficial effects in mouse models of Alzheimer’s disease [16,17,18]. Furthermore, levetiracetam appears to be well tolerated in Alzheimer’s patients who have not experienced seizures [19]. The effect of these drugs on anxiety is varied, as some data indicate that they had no impact on anxiety levels and fear learning in rats. Brivaracetam seems to have a more favorable profile, with fewer aggressive behaviors in preclinical tests than levetiracetam [20]. In contrast, our previous studies have shown that these drugs have different effects on anxiety and memory, with brivaracetam specifically causing some memory disturbances [21,22].
The pharmacotherapy of alcohol addiction remains a pressing issue, as currently registered drugs are not sufficiently effective. Antiseizure drugs are being investigated, and levetiracetam has shown mixed effects, either increasing or decreasing alcohol consumption in mice and rats [23,24]. In clinical studies, levetiracetam decreased alcohol drinking [25,26], although it had no significant effect on heavy-drinking patients [27]. Moreover, the drug had no significant impact on the treatment of alcohol withdrawal syndrome and did not alter the benzodiazepine requirements in patients [28]. However, levetiracetam has shown potential efficacy in reducing co-occurring anxiety disorders in individuals with alcohol dependence [29]. Brivaracetam has not been studied in alcohol dependence patients. The only available study examines its acute interaction with ethanol in healthy males, revealing that brivaracetam enhanced ethanol-induced changes in psychomotor function, attention, and memory [30]. Given the mixed results with levetiracetam and the lack of evaluation for brivaracetam, this study aims to assess the effects of these drugs co-administered with ethanol on associative learning and anxiety-like behaviors in adult rats. The drugs were administered separately to select groups of animals to assess the impact of each SV2A ligand on cognitive functions in rats that have been exposed to ethanol.

2. Materials and Methods

2.1. Animals

Male Wistar rats were purchased from the Mossakowski Institute of Experimental and Clinical Medicine in Warsaw, Poland. The animals weighed between 240 and 300 g (n = 64). All experimental procedures complied with the European Directive 2010/63/EU, ARRIVE guidelines, and Polish governmental regulations regarding experiments on animals (Dz.U.05.33.289) and were approved by the Local Ethical Committee for Experiments on Animals in Łódź, Poland (no. 66/ŁB/121/2018; 9/ŁB231/2022). The rats were accommodated in four per cage, each equipped with a plastic tunnel. Animals were kept on a 12 h dark/light cycle, with a constant room temperature (20–22 °C) and humidity (55 ± 5%). The rats in all groups had free access to commercial chow. Before the start of the experiments, the animals were acclimated to the facility conditions for one week. The experiments were performed between 8:00 a.m. and 4:00 p.m. The rats were allowed to stay in the testing room for approximately 30 min before each behavioral test began.
Thirty-two animals were divided into four groups (C, Eth, Eth + Brv, and Eth + Lev; n = 8) and were involved in the passive avoidance, contextual fear conditioning and cued fear conditioning tests. Another thirty-two rats were also assigned to one of four groups (C, Eth, Eth + Brv, and Eth + Lev; n = 8) and were involved in the elevated plus maze test.

2.2. Drugs and Ethanol Administration

Levetiracetam (Trund®, 10 mg/mL solution; Glenmark Pharmaceuticals, Mumbai, India) or brivaracetam (Briviact®, 10 mg/mL solution; UCB Pharma, Brussels, Belgium) was given via oral gavage to the stomach. The drugs were administered repeatedly once a day for 21 days before the start of behavioral tests at doses of 300 mg/kg b.w. or 6 mg/kg b.w., respectively. The forced ethanol intake model, developed by Majchrowicz [31] and amended by Szmigielski [32], was utilized to minimize the risk that observed changes would be related to the different alcohol consumption between groups. To prepare appropriate alcohol concentrations, 95% food-grade ethanol was used. Three groups of rats received a 20% ethanol: Eth, Eth + Brv, and Eth + Lev in two daily doses: 1.5 g/kg b.w. (0.75 mL/100 g) in the morning and 3.5 g/kg b.w. (1.75 mL/100 g) in the afternoon, via an oral gavage. Additionally, from 4:00 p.m. to 8:00 a.m., these rats had free access to a 5% ethanol solution. Water was available ad libitum during the remaining hours. The control group had unrestricted access to water 24 h a day and received a 1% solution of methylcellulose in the same volume as the drugs (0.2 mL/100 g).

2.3. Behavioral Testing

2.3.1. The Passive Avoidance Test

The passive avoidance test is a behavioral assay designed to measure associative learning and fear-related memory retention in rodents [33]. The test is based on the natural desire of a rodent to remain in dark places and on the association between a specific environmental context and an aversive stimulus. It was conducted using a step-through apparatus (Gemini Avoidance System, San Diego, CA, USA) consisting of two compartments (25 cm × 20 cm × 17 cm) separated by a movable gate.
A single acquisition trial was performed on the first day of the test. Initially, the rat was allowed to explore the dark compartment for 60 s to habituate to the environment. Following this, the light was turned on, and the gate to the dark compartment was opened simultaneously. Since rodents typically prefer dark places, the rat was expected to move into the dark compartment. The gate closed automatically once the rat fully entered the dark compartment, and the animal received a 3 s electric foot shock (0.5 mA) through the floor grid. To help establish an association between the stimulus and the environment, the rat remained in the dark compartment for approximately 15 s. To clean the apparatus between trials, 70% isopropyl alcohol was used.
The retention trial was conducted 24 h after the acquisition trial. The animals experienced a similar trial but without the foot shock. The latency time for the rats to step through to the dark compartment was measured, with a maximum trial duration of 300 s.

2.3.2. Contextual Fear Conditioning

The contextual fear conditioning is a procedure for assessing associative learning and fear responses to a context associated with an aversive stimulus. After returning to a familiar environment, the rat demonstrates fear responses characterized by freezing, defined as a lack of movement aside from breathing. Extended periods of freezing indicate a memory of the unpleasant experience in the familiar environment.
The test was conducted using a fear conditioning system (Ugo Basile, Gemonio, Italy), which includes a sound-attenuating chamber (55 cm × 60 cm × 57 cm) with a speaker and light, as well as an animal box with an electrified floor (30 cm × 34 cm × 41.5 cm). A camera located in the central part of the chamber allowed for monitoring and recording of the animal’s behavior. The contextual fear conditioning was performed after 24 h following the discontinuation of ethanol administration.
Contextual fear conditioning is a two-day test performed according to the method described by [34]. On the first day, a training session begins with a 120 s adaptation period, during which the animal can explore the new environment. Afterwards, an 80 dB sound signal (conditioned stimulus—CS) is presented for 30 s. During the final 2 s of the sound, a foot shock (0.5 mA; unconditioned stimulus—US) is administered. A second similar trial follows after a 2 min break. The animal then remains in the cage for approximately 60 s to consolidate the information. The cage is cleaned with isopropyl alcohol between trials to eliminate any lingering scents.
After 24 h, the rat is returned to the same cage, and the procedure is repeated under similar conditions (light, scent, timing). Each trial lasts 240 s, during which the rat is not exposed to CS or US. The total duration of freezing responses is assessed using Any-Maze 4.73. software. As before, the cage is cleaned with isopropyl alcohol between trials.

2.3.3. Cued Fear Conditioning

The cued fear conditioning is a test used to evaluate associative learning in animals, similar to the contextual fear conditioning. The key differences between those procedures occur on the test second day. During this phase, the animal is introduced to new surroundings with a familiar CS, while the US is not utilized [34]. This study was conducted 24 h after the discontinuation of ethanol administration, using the same apparatus as in the contextual fear conditioning.
The animals involved in this study had previously participated in the contextual fear conditioning. On the first test day, the training session was analogous to the contextual fear conditioning test. On the second test day, the rats underwent the cued fear conditioning test, which occurred three hours after completing the contextual fear conditioning test. The appearance of the walls and floor was altered, and the cage was thoroughly cleaned between trials using isopropyl alcohol mixed with vanilla extract. Initially, the rat was placed in the device for a 180 s adaptation period. Then, the animal was exposed to a familiar sound stimulus at 80 dB for three minutes, during which the total time of freezing responses was recorded using Any-Maze 4.73. software.

2.3.4. Elevated Plus Maze Test

The elevated plus maze was conducted in an apparatus consisting of two open arms (50 cm × 10 cm), two closed arms (50 cm × 10 cm × 40 cm), and a central platform (5 cm × 5 cm). The maze was situated approximately 50 cm above the floor. The test was performed as described previously [21]. Briefly, the animal was placed on the central platform and allowed to explore freely for five minutes. A camera mounted above the maze recorded the trial. The time spent in the open arms, the number of entries into the open arms, and the distance traveled were analyzed using the Any-Maze 4.73. software. The time spent in the open arms was calculated as a percentage of the total time spent in both the open and closed arms. Similarly, the number of entries into the open arms was expressed as a percentage of the total entries into both the open and closed arms. An entry into the arm was counted when all four paws were placed inside. The maze was cleaned with isopropyl alcohol between trials to maintain a consistent fragrance.

2.4. Data Analysis

Statistical analysis was performed using GraphPad Prism 6.0 software (GraphPad, San Diego, CA, USA). The results are presented as mean values ± SEM (cued fear conditioning) and median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line) (all other tests). The normality of the distribution was checked using the Kolmogorov–Smirnov test, with Lilliefors correction. One-way ANOVA was applied for the cued fear conditioning test. Due to the non-normal distribution of results, non-parametric tests were used for other tests, with post hoc statistical analysis conducted using Dunn’s test. A p-value of 0.05 or lower was considered statistically significant for all tests.

3. Results

3.1. The Effect of Levetiracetam or Brivaracetam Co-Administered with Ethanol on Associative Memory in the Passive Avoidance Test

After three weeks of the administration of ethanol and drugs, the rats that received ethanol exhibited the shortest step-through latency, which was significant compared to the control group (Figure 1). Levetiracetam significantly prolonged the latency compared to the ethanol group, while brivaracetam did not result in any improvement in the measured time.

3.2. The Effect of Levetiracetam or Brivaracetam on Associative Memory in the Contextual Fear Conditioning Test 24 h After the Discontinuation of Ethanol Administration

Brivaracetam administered for 23 days significantly reduced the proportion of freezing responses compared to the control group (Figure 2). In contrast, levetiracetam did not have a significant impact on this parameter. Additionally, a decrease in freezing behavior was observed in the rats that had previously only been exposed to ethanol. However, this difference was not significant when compared to the other groups.
Figure 1. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on associative memory in passive avoidance. C—control group, Eth—ethanol group, Eth + Brv—ethanol and brivaracetam group, Eth + Lev—ethanol and levetiracetam group; * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Figure 1. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on associative memory in passive avoidance. C—control group, Eth—ethanol group, Eth + Brv—ethanol and brivaracetam group, Eth + Lev—ethanol and levetiracetam group; * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Futurepharmacol 05 00045 g001
Figure 2. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on % freezing after 24 h of abstinence in the contextual fear conditioning test. * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Figure 2. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on % freezing after 24 h of abstinence in the contextual fear conditioning test. * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Futurepharmacol 05 00045 g002

3.3. The Effect of Levetiracetam or Brivaracetam on Associative Memory in the Cued Fear Conditioning Test 24 h After the Discontinuation of Ethanol Administration

The rats were introduced to a new environment without a familiar sound stimulus during the first three minutes of the test. During this period, the rats that had previously received ethanol exhibited the lowest freezing responses. However, this decrease was not statistically significant compared to other groups (Figure 3). In the following three minutes of the test, the rats were exposed to a familiar sound signal. The animals that received both brivaracetam and ethanol displayed the lowest freezing responses, but this difference was also not significant.

3.4. The Effect of Levetiracetam or Brivaracetam on Anxiety-like Behavior in the Elevated Plus Maze Test 24 h After the Discontinuation of Ethanol Administration

The rats that had previously received ethanol spent less time in the open arms (Figure 4) and demonstrated reduced open-arm entries (Figure 5) and traveled distance (Figure 6). These differences were statistically significant compared to the control group. Withdrawal animals receiving levetiracetam also exhibited a significant reduction in the traveled distance compared to control rats, but other parameters were not affected. No significant changes were observed in animals receiving brivaracetam.

4. Discussion

The present study demonstrates that levetiracetam and brivaracetam have varying impacts on ethanol-induced memory impairment and anxiety-like behaviors in rats. Levetiracetam co-administered with ethanol improved associative learning in the passive avoidance test, while brivaracetam did not affect it. Furthermore, brivaracetam disturbed associative learning in withdrawal rats, especially in the contextual fear conditioning test. Neither drug significantly affected the elevated anxiety level during the abstinence period. However, withdrawal-induced disturbance of locomotor activity persisted, particularly in levetiracetam-treated animals.
The first test used to evaluate associative learning and fear-related memory was the passive avoidance test. Tests were performed during the alcohol administration period. Ethanol disturbed memory in rats, which was demonstrated by a reduced step-through latency. Levetiracetam significantly improved memory in the rodents, while brivaracetam did not affect alcohol-induced disturbances. In the available literature, there is no data about the impact of levetiracetam and brivaracetam on associative learning in the alcohol model. In our previous study, levetiracetam administered repeatedly at 300 mg/kg b.w did not impair memory in the passive avoidance test. However, temporary adverse effects were seen when the drug was given acutely [21]. Similarly, repeated administration of brivaracetam at 6 mg/kg b.w. did not impact associative learning. Memory alterations were only seen in rats that received a high acute dose of brivaracetam [22]. Moreover, brivaracetam has not been tested in passive avoidance assessments in other contexts. On the other hand, the influence of levetiracetam on associative memory was assessed in a streptozotocin-induced rat model of Alzheimer’s disease. It has been demonstrated that the drug administered for 20 days at doses of 100 mg/kg b.w. and 150 mg/kg b.w. i.p. attenuated memory impairments. This positive outcome was associated with a reduction in the loss of hippocampal neurons and a restoration of altered redox status [35]. However, the drug was administered at a dose of 310 mg/kg p.o. impaired the retention memory in Wistar rats, which was linked with increased levels of malondialdehyde (MDA), a marker of oxidative stress [36].
Contextual and cued fear conditioning are other tests utilized to evaluate associative learning. These tests were conducted 24 h after the cessation of a twenty-three-day ethanol intake period. In contextual conditioning, brivaracetam disturbed the memory of unpleasant stimuli, as evidenced by a diminished freezing response in the rats. The duration of immobility is an anxious response that reflects the association between unpleasant stimuli and the environment. Moreover, the lowest freezing response was observed in these animals when they were exposed to familiar sound stimuli during cued conditioning. However, this effect was not significant. On the contrary, levetiracetam did not influence associative learning outcomes in either test. Currently, the literature lacks studies on the effects of brivaracetam or levetiracetam administered chronically in conditioning tests, and drugs have only been examined in acute doses. Sanon et al. (2018) compared the impact of levetiracetam and brivaracetam administered in acute doses (300 mg/kg b.w. or 30 mg/kg b.w. i.p., respectively) on behavioral effects like learning and anxiety. The freezing responses to the sound stimulus were similar among the drug groups in both sham and epileptic rats, which indicates that both drugs had no effect on anxiety-related memory [20]. Moreover, Devi and Ohno (2013) investigated the effect of an acute dose of levetiracetam in a mouse model of Alzheimer’s disease and in mice with an aging-associated memory decline. The animals received a single intraperitoneal injection of levetiracetam either before training, immediately following training, or three hours post-training. Pretraining administration of levetiracetam improved memory in aged mice. A similar beneficial effect was noted in rats when the drug was given immediately post-training. However, no positive effect was observed when the drug was administered three hours after training. Additionally, levetiracetam did not significantly affect memory deficits in the Alzheimer’s model mice [37].
Finally, the elevated plus maze was used to evaluate anxiety 24 h after alcohol withdrawal. Rats that had previously received only ethanol for three weeks demonstrated an exaggerated level of anxiety expressed as a significant decrease in time in open arms and fewer entries to these arms. Both brivaracetam and levetiracetam have shown a tendency to improve abstinence-induced anxiety levels, particularly noted by an increase in entries into the open arms. However, these differences were not statistically significant. Additionally, ethanol negatively affected locomotor activity, resulting in a significant decrease in the distance traveled. A similar significant reduction in distance was noted in animals receiving levetiracetam. In our previous study, levetiracetam administered for three weeks at a dose of 300 mg/kg b.w. similarly decreased locomotor activity without affecting the anxiety level in rats [21]. Conversely, we reported that administering brivaracetam at a dose of 6 mg/kg body weight for three weeks did not affect locomotor activity but increased anxiety in the rats [22]. Furthermore, Sanon et al. (2018) also compared the effect of acute doses of both drugs on anxiety in an elevated plus maze test and found that neither drug influenced anxiety nor locomotor activity [20]. In turn, a beneficial effect of levetiracetam was observed in rats exposed to adolescent stress, which triggers changes in adulthood similar to those observed in animal models of schizophrenia. Although levetiracetam administered at an acute dose of 10 mg/kg i.p. did not impact anxiety-related behavior in the elevated plus maze, it reversed anxiety-like responses in the light–dark box [38].
The effect of levetiracetam on locomotor activity was also examined previously in ethanol-exposed mice. In this study, levetiracetam (10–100 mg/kg i.p.) did not significantly affect locomotor activity. However, when given prior to an acute dose of ethanol, levetiracetam reduced both acute and repeated ethanol-induced locomotor sensitization [39]. In the above-mentioned study, Sanon et al. (2018) investigated the effects of acute doses of levetiracetam and brivaracetam on locomotion and reported that neither drug caused any disturbances in locomotor activity [20].
The efficacy of levetiracetam was also assessed in 37 patients with alcohol use disorder. The drug was administered at a dose of 2000 mg/kg b.w. p.o. for 14 weeks, including a 2-week taper period. Levetiracetam, similarly to the other studied drugs topiramate and zonisamide, did not affect anxiety as determined using the Hamilton Anxiety scale. Moreover, the drug did not impair verbal fluency and working memory, determined, respectively, using the Controlled Word Association Test and The Rey Audio Visual Learning Test, in contrast to zonisamide and topiramate. However, levetiracetam did not significantly attenuate drinking, except for the percentage of days with heavy drinking [25]. Moreover, levetiracetam seemed to be effective in the treatment of patients with co-occurring alcohol use and anxiety disorders. The drug administered in doses of up to 1500 mg for up to 8 weeks reduced ethanol consumption and anxiety symptoms during this period (n = 3) [29].
The observed behavioral changes, including levetiracetam’s improvement in memory in the passive avoidance test and brivaracetam’s disturbing effect in the contextual fear conditioning test, might be related to the differential interaction of these drugs with the SV2A protein. The previous results showed that drugs bind to different sites or affect varied conformational states of the SV2A protein [40]. However, the same authors demonstrated that the binding sites of these drugs are closely related, but they interact with them in a different way [8]. Additionally, levetiracetam, unlike brivaracetam, is not a selective modulator of the SV2A protein, and the observed differences in effects might also be associated with the inhibition of high-voltage-activated calcium channels by levetiracetam [9]. These varied effects might be particularly relevant in the hippocampus and the amygdala, which are brain structures associated with memory processes and anxiety. However, since this study did not evaluate any biochemical changes, which is a limitation of this study, further investigations are required to understand how the drugs impact SV2A protein activity in these brain areas. Currently, there is limited information available about how ethanol and both drugs affect them. In our previous pharmaco-EEG study, levetiracetam was found to reduce the sensitivity of the hippocampus to the effects of ethanol in rabbits [41]. However, no alterations were noted in hippocampal GABAergic and glutamatergic transmissions in rats receiving levetiracetam and ethanol for three weeks [42]. The observed beneficial effect of levetiracetam may be related to the neuroprotective activity observed mainly in varied epilepsy models [43,44,45]. No information is available about the impact of brivaracetam on the hippocampus and amygdala in alcohol-drinking models. Nevertheless, the neuroprotective effects of brivaracetam on the hippocampus have been identified in a rat model of temporal lobe epilepsy [46].
To sum up, levetiracetam shows a beneficial effect on associative memory in rats, especially during the alcohol-drinking period, while brivaracetam appears to exaggerate or does not affect alcohol-induced memory disturbances. However, withdrawal-induced disturbance of locomotor activity persisted, particularly in rats receiving levetiracetam. Further research is needed to clarify the mechanisms behind these effects and to understand the differences in the observed outcomes. These differences may be associated with the drug’s effects on the hippocampus and amygdala, as well as their varying influences on SV2A protein, calcium channels, or potential neuroprotective properties.

Author Contributions

Conceptualization, methodology, software, E.Z.; validation, formal analysis, investigation, data curation, E.Z. and B.P.; writing—original draft preparation, E.Z.; writing—review and editing, B.P.; visualization, E.Z.; supervision, E.Z.; project administration, E.Z.; funding acquisition, E.Z. and B.P. All authors have read and agreed to the published version of the manuscript.

Funding

This study was supported by a research Grant No: 503-31-001 from the Medical University, Łódz, Poland. The funding source had no other role other than financial support.

Institutional Review Board Statement

The study was approved by the Local Ethical Committee for Experiments on Animals in Łódź, Poland (resolutions no. 66/ŁB/121/2018; 9/ŁB231/2022).

Informed Consent Statement

Not applicable.

Data Availability Statement

All data supporting the reported results are included in this manuscript.

Acknowledgments

The authors would like to thank Jakub Wojcieszak for his help in data analysis.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 3. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on % freezing after 24 h of abstinence in the cued fear conditioning test. Data are presented as mean values ± SEM.
Figure 3. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on % freezing after 24 h of abstinence in the cued fear conditioning test. Data are presented as mean values ± SEM.
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Figure 4. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on time in the open arms in the elevated plus maze (EPM). * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Figure 4. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on time in the open arms in the elevated plus maze (EPM). * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
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Figure 5. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on open-arm entries in the elevated plus maze (EPM). * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Figure 5. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on open-arm entries in the elevated plus maze (EPM). * p < 0.05. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
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Figure 6. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on locomotor activity in elevated plus maze (EPM). * p < 0.05; ** p < 0.01. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
Figure 6. The effect of prolonged administration of levetiracetam or brivaracetam with ethanol on locomotor activity in elevated plus maze (EPM). * p < 0.05; ** p < 0.01. Data are presented as median (horizontal bar), first and third quartiles (vertical column), and minimum and maximum (vertical line); outlier values are represented by circles.
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Zwierzyńska, E.; Pietrzak, B. The Effect of Co-Administration of Levetiracetam or Brivaracetam with Ethanol on the Associative Learning and Anxiety Level of Rats. Future Pharmacol. 2025, 5, 45. https://doi.org/10.3390/futurepharmacol5030045

AMA Style

Zwierzyńska E, Pietrzak B. The Effect of Co-Administration of Levetiracetam or Brivaracetam with Ethanol on the Associative Learning and Anxiety Level of Rats. Future Pharmacology. 2025; 5(3):45. https://doi.org/10.3390/futurepharmacol5030045

Chicago/Turabian Style

Zwierzyńska, Ewa, and Bogusława Pietrzak. 2025. "The Effect of Co-Administration of Levetiracetam or Brivaracetam with Ethanol on the Associative Learning and Anxiety Level of Rats" Future Pharmacology 5, no. 3: 45. https://doi.org/10.3390/futurepharmacol5030045

APA Style

Zwierzyńska, E., & Pietrzak, B. (2025). The Effect of Co-Administration of Levetiracetam or Brivaracetam with Ethanol on the Associative Learning and Anxiety Level of Rats. Future Pharmacology, 5(3), 45. https://doi.org/10.3390/futurepharmacol5030045

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