Chlordiazepoxide against signalling, receptor and regulatory proteins of breast cancer: a structure-based in-silico approach.

Among the most prevalent forms of cancer are breast, lung, colon-rectum, and prostate cancers, and breast cancer is a major global health challenge, contributing to 2.26 million cases with approximately 685,000 deaths worldwide in 2020 alone, typically beginning in the milk ducts or lobules that produce and transport milk during lactation and it is becoming challenging to treat as the tissues are developing resistance, which makes urgent calls for new multitargeted drugs. The multitargeted drug design provides a better solution, simultaneously targeting multiple pathways, even when the drug resists one, it remains effective for others. In this study, we included four crucial proteins that perform signalling, receptor, and regulatory action, namely- NUDIX Hydrolases, Dihydrofolate Reductase, HER2/neu Kinase and EGFR and performed multitargeted molecular docking studies against human-approved drugs using HTVS, SP and extra precise algorithms and filtered the poses with MM\GBSA, suggested a benzodiazepine derivative chlordiazepoxide, used as an anxiolytic agent, can be a multitargeted inhibitor with docking and MM\GBSA score ranging from - 4.628 to - 7.877 and - 18.59 to - 135.86 kcal/mol, respectively, and the most interacted residues were 6ARG, 6GLU, 3TRP, and 3VAL. The QikProp-based ADMET and DFT computations showed the suitability and stability of the drug candidate followed by 100 ns MD simulation in water and MMGBSA on trajectories, resulting in stable performance and many intermolecular interactions to make the complexes stable, which favours that chlordiazepoxide can be a multitargeted breast cancer inhibitor. However, experimental validation is needed before its use.

Discriminative-stimulus effects of cannabidiol oil in Sprague-Dawley rats.

Cannabidiol (CBD) is one of the major centrally active phytocannabinoid components of cannabis, and has been approved by the FDA only for the treatment of seizures associated with three rare disorders. It has also been touted as a potential treatment for anxiety in place of more traditional treatments like benzodiazepines. Although there is some evidence of anxiolytic effects of CBD, its suitability as a substitute for benzodiazepines is unknown. This experiment was designed to assess the extent to which CBD shares interoceptive discriminative-stimulus properties with the anxiolytic drug chlordiazepoxide (CDP), a benzodiazepine. In the present experiment, a range of doses (0-1569 mg/kg) of over-the-counter CBD oil was administered (i.g.) in male Sprague-Dawley rats trained to discriminate 5.6 mg/kg CDP from saline. Due to the long time-course effects of CBD, generalization tests were conducted at 90 and 120 min post-CBD administration. The two highest doses of CBD tested (1064 and 1569 mg/kg) were found to partially substitute for 5.6 mg/kg CDP, with mean percent responding on the CDP-associated lever reaching above 20% at time 2 (120 min post-CBD administration), suggesting that high doses of the over-the-counter CBD oils used in this experiment share interoceptive discriminative-stimulus properties to some degree with CDP. These results are novel in comparison to existing research into stimulus effects of CBD, in which substitution for benzodiazepines has not previously been observed.

Comparison of the Effect of Chlordiazepoxide and Transcranial Alternating Current Stimulation on Blood Potassium Loss Due to Preoperative Anxiety.

PURPOSE: This study evaluated and compared the effect of chlordiazepoxide and transcranial alternating current stimulation (tACS) on changes in blood potassium levels caused by preoperative anxiety. DESIGN: This randomized, double-blind placebo control study was performed on 100 patients undergoing surgery with the American Society of Anesthesiologists physical status (ASA I) who went through surgery for the first time. METHODS: Patients were classified into four groups of real or sham tACS, chlordiazepoxide, and placebo. The Amsterdam Preoperative Anxiety information Scale (APAIS) and serum potassium levels were used to collect data. The results were analyzed using the Kolmogorov-Smirnov tests, independent t test, Pearson correlation, and χ2 test. FINDINGS: There was no baseline difference between the groups. A significant difference was found between real tACS and the chlordiazepoxide group in plasma potassium level (P = .017). CONCLUSIONS: The results showed that real tACS was more effective than chlordiazepoxide in preventing the decrease of plasma potassium level in the preoperative period. Assessing the efficacy of the other types of brain electrical interventions is suggested for future studies.

Burrowing as an index of inflammatory pain in male vs. female rats.

The study objective was to determine whether burrowing behavior is useful as a functional index of pain in both male and female rats, and whether a 'no-training' protocol can be used to increase testing efficiency. Adult Sprague-Dawley rats were injected in one or both hindpaws with oil vehicle or complete Freund's adjuvant (CFA); starting the next day, the amount of gravel each rat burrowed out of a tube in 1 h was measured daily for ≤7 days. Without preliminary training on the burrowing procedure, CFA reliably suppressed burrowing for 2-3 days compared to controls, in both sexes. However, whereas unilateral CFA completely suppressed burrowing 1-day post-CFA in nearly all males, bilateral CFA was required to do so in females. When administered 30 min before testing, once daily for 5 days post-CFA, the nonsteroidal anti-inflammatory drug ketoprofen (0.01-3.2 mg/kg) and the opioid morphine (0.1-3.2 mg/kg) significantly increased CFA-suppressed burrowing, whereas the purported cannabinoid analgesic Δ 9 -tetrahydrocannabinol (0.01-2.0 mg/kg) did not. The benzodiazepine chlordiazepoxide (1.25-10 mg/kg), included as a 'true negative' control, also did not restore CFA-suppressed burrowing in either sex. However, in CFA-treated males only, chlordiazepoxide decreased burrowing, suggesting that anxiety may contribute to burrowing in males but not females that are in pain. Overall these results suggest that burrowing is a valid, functional index of inflammatory pain in both sexes, and training on the burrowing procedure is not necessary. However, females are more avid burrowers than males, which should be considered when both sexes are used in inflammatory pain testing.

New Saccharin Salt of Chlordiazepoxide: Structural and Physicochemical Examination.

Since the formation of organic salts can improve the solubility, bioavailability, and stability of active pharmaceutical ingredients, the aim of this work was to prepare an organic salt of chlordiazepoxide with saccharin. To achieve this goal, the saccharin salt of chlordiazepoxide was obtained from a physical mixture of both components by grinding them with a small volume of solvent and by crystallizing them with complete evaporation of the solvent. The resulting salt was examined by methods such as Powder X-ray Diffraction (PXRD), Single Crystal X-ray Diffraction (SCXRD), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FT-IR), and Raman spectroscopy. The results of the studies proved that saccharin salt of chlordiazepoxide crystallizes in the orthorhombic Pbca space group with one chlordiazepoxide cation and one saccharin anion in the asymmetric unit. In the crystal of the title compound, the chlordiazepoxide cation and the saccharin anion interact through strong N-H···O hydrogen bonds and weak C-H···O hydrogen bonds. The disappearance of the N-H band in the FT-IR spectrum of saccharin may indicate a shift of this proton towards chlordiazepoxide, while the disappearance of the aromatic bond band in the chlordiazepoxide ring in the Raman spectrum may suggest the formation of intermolecular hydrogen bonds between chlordiazepoxide molecules. The melting point of the salts differs from that of the starting compounds. Thermal decomposition of the salt begins above 200 °C and shows at least two overlapping stages of mass loss. In summary, the results of the research showed that the crystalline salt of the saccharin and chlordiazepoxide can be obtained by various methods: grinding with the addition of acetonitrile and crystallization from acetonitrile or a mixture of methanol with methylene chloride.

Chlordiazepoxide-induced delirium in a patient undergoing alcohol withdrawal: a case report.

BACKGROUND: Ethanol dependence is associated with a discontinuation withdrawal delirium. Chlordiazepoxide is frequently successfully used in its treatment. CASE PRESENTATION: A 27-year-old, Caucasian female with ethanol dependence who had objective symptoms of withdrawal experienced worsening of her delirium after administration of chlordiazepoxide, but improved with lorazepam and cleared with discontinuation of benzodiazepine administration. CONCLUSIONS: Worsening of delirium appears to be related to the specific use of chlordiazepoxide, but the mechanism of this effect is not clear. While this case does not alter the standard care of ethanol dependence, it does alert clinicians that our treatment approach may not be fully benign.

Further disentangling the motivational processes underlying benzodiazepine hyperphagia.

In addition to their well-known anxiolytic functions, benzodiazepines produce hyperphagia. Previously, we reported that the benzodiazepine, chlordiazepoxide (CDP), increased consumption of both normally-preferred and normally-avoided taste stimuli during long-term (1 h) tests, primarily through changes in licking microstructure patterns associated with hedonic taste evaluation, whereas there was little effect on licking microstructure measures associated with post-ingestive feedback. In this study, we further examined the hedonic and motivational specificity of CDP effects on ingestive behavior. We tested brief access (15 s) licking responses for tastants spanning all taste qualities after treatment with either CDP (5 or 10 mg/kg) or the non-benzodiazepine anxiolytic, buspirone (1.5 or 3 mg/kg). A between-subjects, counterbalanced design compared the CDP or buspirone effects on licking responses for water and a range of weak to strong concentrations of NaCl, Q-HCl, citric acid, MSG, saccharin, and capsaicin under water-restricted (23 h) conditions; and sucrose, saccharin, and MSG under water-replete conditions. In a dose dependent manner, CDP increased licking for taste stimuli that were normally-avoided after saline treatment, with a notable exception observed for the trigeminal stimulus, capsaicin, which was not affected at any concentration or drug dose, suggesting a taste-specific effect of CDP on orosensory processing. Under water-replete conditions, CDP dose-dependently increased licking to normally-accepted concentrations of sucrose, saccharin, and MSG. There was no effect of either drug on licks for water under either water-restricted or water-replete conditions. Buspirone slowed oromotor coordination by increasing brief interlick intervals, but it did not affect licking for any concentrations of the tastants. Overall, these results indicate that benzodiazepines selectively enhance the hedonic acceptance of gustatory orosensory stimuli, independent of general anxiolytic or oromotor coordination effects, or physiological states such as thirst.

Creatine@SiO2 @Fe3 O4 nanocomposite as an efficient sorbent for magnetic solid-phase extraction of escitalopram and chlordiazepoxide from urine samples through quantitation via HPLC-UV.

An efficient, cost-effective, and fast-synthesis method is presented in the current study to prepare magnetic nanoparticles covered by cheap and nitrogen-rich creatine. The hydrothermal method was used for the synthesis of the magnetic core. The prepared magnetic core was then covered by SiO2 and subsequently functionalized using creatine. The prepared creatine@SiO2 @Fe3 O4 was utilized as a sorbent in the magnetic solid-phase extraction of the selected antidepressants including escitalopram and chlordiazepoxide as the model drugs. The extracted drugs were desorbed by a suitable organic solvent and analyzed by high-performance liquid chromatography equipped with an ultraviolet detection system. The influence of different variables on the magnetic solid-phase extraction method was examined by the Plackett-Burman and Box-Behnken designs for screening and optimization, respectively. Under the obtained optimum conditions, the linear ranges of the method were found to be in the range of 1-500 µg L-1 . The limits of detection and limits of quantification were in the range of 0.27-0.63 µg L-1 and 0.89-1.93 µg L-1 for the selected analytes, respectively. Furthermore, the enrichment factors were found to be 79.8 and 92.7 for chlordiazepoxide and escitalopram, respectively. The method was successfully employed for the analysis of selected drugs in urine samples.

Association of benzodiazepines, Z-drugs, pregabalin, and melatonin with traffic accidents: A nationwide cohort and case-crossover study in Danish adults.

BACKGROUND: Benzodiazepines, Z-drugs, pregabalin, and melatonin (BZPMs) have been associated with a higher risk of traffic accidents, but the evidence is inconsistent, and lacking for newer drugs. AIM: To examine the association of BZPMs with risk of traffic accidents. METHODS: All Danish adults (n = 3,823,588) were followed for redeemed prescriptions of BZPM and for incident traffic accidents registered in Danish registers from 2002 through 2018. Associations were examined in cohort and case-crossover designs using Cox proportional hazard and conditional logistic regression with adjustment for co-variables. RESULTS: A total of 19.3% (n = 738,019) of all participants initiated treatment with BZPMs. During the mean follow-up of 10.3 years, 595,173(15.5%) of participants were involved in a traffic accident. In the cohort analysis, all BZPMs besides pregabalin were associated with a higher risk of traffic accidents in adults below 70 years, with chlordiazepoxide showing the strongest association (hazard ratio (HR)age 18-49 = 1.76, 95% confidence interval (CI): 1.67-1.86 and HRage 50-69 = 1.84, 95% CI: 1.70-2.00). In the older age groups, the specific BZPM medications were associated with lower or no risk of traffic accidents. However, in case-time-crossover analysis with inherited control for confounders, no BZPM medication was positively associated with traffic accidents, except for chlordiazepoxide, which had a higher odds ratio in middle-aged group (1.62, 95% CI: 1.15-2.29). CONCLUSIONS: This study does not fully support that BZPM use is a risk factor for traffic accidents. However, a positive association was found for chlordiazepoxide, which is approved for treatment of acute alcohol withdrawal.

Effects of chlordiazepoxide on pausing during rich-to-lean transitions.

Extended pausing during discriminable transitions from rich-to-lean conditions can be viewed as escape (i.e., rich-to-lean transitions function aversively). Thus, an anxiolytic drug would be predicted to mitigate the aversiveness and decrease pausing. In the current experiment, pigeons' key pecking was maintained by a multiple fixed-ratio fixed-ratio schedule of rich (i.e., larger) or lean (i.e., smaller) reinforcers. Intermediate doses (3.0-10.0 mg/kg) of chlordiazepoxide differentially decreased median pauses during rich-to-lean transitions. Relatively small decreases in pauses occurred during lean-to-lean and rich-to-rich transitions. Effects of chlordiazepoxide on pausing occurred without appreciable effects on run rates. These findings suggest that signaled rich-to-lean transitions function aversively.

Caracterización de la prescripción de ansiolíticos en adultos mayores institucionalizados en un hogar de ancianos / Characterization of the prescription of anxiolytics in institutionalized older adults in the nursing home

El objetivo de este estudio fue caracterizar la prescripción de los medicamentos ansiolíticos utilizados en población de adultos mayores institucionalizados en el hogar de ancianos de Pinar del Río durante el año 2017.Se realizó un estudio descriptivo transversal, con recogida de datos retrospectiva, sobre prescripción de medicamentos ansiolíticos en la población de adultos mayores institucionalizados en el hogar de ancianos, se analizó la forma de utilización de los medicamentos, su indicación y prescripción con elementos de esquema terapéutico y factores que condicionan los hábitos de prescripción. Se trabajó con el universo (U= 98) de estudio el cual estuvo conformado por el total de pacientes institucionalizados, que estaban consumiendo ansiolíticos. Se revisaron las historias clínicas individuales y se confeccionó un modelo de recolección de datos.El medicamento más consumido por los adultos mayores fue el nitrazepam (41,8 %), siendo este a su vez el más consumido por el sexo masculino, no así para el femenino que resultó ser el clorodiazepóxido (64,6 %), el grupo de edad que más predominó fue el de 60-69 años, asimismo los viudos y el nivel educacional primario, el 79,5 % de los ancianos consume otros medicamentos que poseen interacción farmacocinética. El profesional que más indicó fue el médico de familia, la prescripción e intervalos entre dosis fue adecuada, la prescripción se consideró no racional.La prescripción de ansiolíticos en la población objeto de estudio, disminuye a medida que aumenta la edad, los más consumidores son los del sexo masculino y los institucionalizados por abandono familiar, esto apunta a la necesidad de continuar trabajando desde el nivel primario de atención dado que es de donde proceden estos ancianos.

The objective of this study was to characterize the prescription of anxiolytic medications used in the institutionalized elderly population at the Pinar del Río Nursing Home during 2017.A cross-sectional descriptive study was carried out, with retrospective data collection, on the prescription of anxiolytic medications in the population of institutionalized older adults in the Nursing Home, the form of use of the medications, their indication and prescription with elements of the therapeutic scheme was analyzed and factors that condition prescription habits. We worked with the universe (U = 98) of the study, which was made up of the total number of institutionalized patients who were consuming anxiolytics. Individual medical records were reviewed and a data collection model was created.The drug most consumed by older adults was nitrazepam (41.8%), this in turn being the most consumed by males, not so for females, which turned out to be chlorodiazepoxide (64.6%), the group The most prevalent age group was 60-69 years, likewise widowers and primary educational level, 79.5% of the elderly consume other drugs that have pharmacokinetic interaction. The professional who indicated the most was the family doctor, the prescription and intervals between doses were adequate, the prescription was considered non-rational.The prescription of anxiolytics in the population under study decreases as age increases, the most consumers are those of the male sex and those institutionalized due to family abandonment, this points to the need to continue working from the primary level of care since that is where these elders come from.

Acute lead poisoning: a diagnostic challenge in the emergency department.

Acute abdominal pain is a common presentation to the emergency department (ED). Ruling out life-threatening causes and giving pain relief are the most important tasks in ED. We describe a 32-year-old man who presented to ED with abdominal pain and vomiting which was unrelieved by usual doses of analgesic. Extensive investigations revealed no significant abnormalities. On further probing, he admitted taking traditional medications for infertility. The toxicological panel revealed a high blood lead level, leading to a diagnosis of acute lead toxicity. Chelation therapy with D-penicillamine was initiated and the patient's abdominal pain resolved within 4 days.

Effects of linalool on extinction of mouse operant behaviour.

Linalool is an enanitomer monoterpene compound identified as the pharmacologically active constituent in a number of essential oils and has been reported to display anxiolytic properties in humans and in animal models and to exert both GABAergic and glutamatergic effects. In Experiment 1 linalool (100, 200, and 300, i.p.) had no significant effects compared with saline in an activity tracker with C57BL/6j mice. Experiment 2 assessed the effects on operant extinction with mice of chlordiazepoxide at a dose (15 mg/kg, i.p.) previously shown to facilitate extinction, and the same doses of linalool, compared with saline. Linalool had a dose-related facilitatory effect on extinction. While the effects of the highest dose of linalool most closely resembled the effects of chlordiazepoxide, the pattern of results suggested that linalool may affect both the acquisition of extinction learning, which is influenced by glutamatergic processes, and the expression of extinction, known to be affected by GABAergic agents such as chlordiazepoxide.

The elevated gradient of aversion: a new apparatus to study the rat behavior dimensions of anxiety, fear, and impulsivity.

Few behavioral tests allow measuring several characteristics and most require training, complex analyses, and/or are time-consuming. We present an apparatus based on rat exploratory behavior. Composed of three different environments, it allows the assessment of more than one behavioral characteristic in a short 3-min session. Factorial analyses have defined three behavioral dimensions, which we named Exploration, Impulsivity, and Self-protection. Behaviors composing the Exploration factor were increased by chlordiazepoxide and apomorphine and decreased by pentylenetetrazole. Behaviors composing the Impulsivity factor were increased by chlordiazepoxide, apomorphine, and both acute and chronic imipramine treatments. Behaviors composing the Self-protection factor were decreased by apomorphine. We submitted Wistar rats to the open-field test, the elevated-plus maze, and to the apparatus we are proposing. Measures related to exploratory behavior in all three tests were correlated. Measures composing the factors Impulsivity and Self-protection did not correlate with any measures from the two standard tests. Also, compared with existing impulsivity tests, the one we proposed did not require previous learning, training, or sophisticated analysis. Exploration measures from our test are as easy to obtain as the ones from other standard tests. Thus, we have proposed an apparatus that measured three different behavioral characteristics, was simple and fast, did not require subjects to be submitted to previous learning or training, was sensitive to drug treatments, and did not require sophisticated data analyses.

Lorazepam versus chlordiazepoxide for the treatment of alcohol withdrawal syndrome and prevention of delirium tremens in general medicine ward patients.

Alcohol withdrawal syndrome (AWS) is a serious complication of abrupt alcohol cessation. Severe AWS can develop into delirium tremens (DT), which is potentially life-threatening. Lorazepam (LOR) and chlordiazepoxide (CDE) are mainstays of therapy for AWS. Current literature lacks studies comparing outcomes between the two drugs for patients who are not in a de-addiction ward specifically for withdrawal treatment. The primary objective of the study was to determine the incidence rate of DT between the groups. Of 2112 patients screened, 142 met inclusion criteria (LOR = 74, CDE = 68). Baseline characteristics were similar between groups. No significant difference in the primary outcome of DT development was observed (7% LOR, 9% CDE; p = 0.76). No significant differences in cumulative doses of scheduled LOR or CDE were observed (LOR 14.6 ± 8 mg, CDE 15.4 ± 12; p = 0.64). However, significant differences were found in the amount of "as needed" (PRN) LOR required for the two groups (LOR 3.2 ± 4 mg, CDE 6.6 ± 13 mg; p = 0.03) and the amount of scheduled plus PRN LOR required (LOR 17.7 ± 10 mg, CDE 21.9 ± 14 mg; p = 0.04). Doses are reported in LOR equivalents. There were no observed differences in duration of treatment (LOR 3.6 ± 1.3 days, CDE 3.9 ± 2.1 days; p = 0.3) or length of stay (LOR 5.28 ± 3.8 days, CDE 4.73 ± 4.2 days p = 0.4). No adverse events related to BZD were noted in either group. Hospital outcomes did not differ between the groups, but patients treated with CDE may require more adjuvant therapy to control symptoms of AWS. Both agents appear equally effective at preventing the development of DT in those patients admitted to general medicine wards.

Responses to positive and aversive stimuli in estrous female rats housed in a seminatural environment: Effects of yohimbine and chlordiazepoxide.

The behavioral effects of putative anxiolytic and anxiogenic drugs are usually evaluated in highly standardized tests. Here, we determined the effects of such drugs in rats housed in mixed sex groups in a seminatural environment. Sexually receptive female Wistar rats were treated with either the anxiolytic drug chlordiazepoxide (2 mg/kg), the anxiogenic drug yohimbine (1 mg/kg), or saline (1 ml/kg). Different emotional challenges eliciting purportedly positive affect (lavender odor, Mozart's music, chocolate flavored food) or negative affect (white noise, fox odor) were then introduced into the seminatural environment. A co-occurrence analysis revealed that music was rather aversive to the rats, as were white noise and fox odor. Lavender and chocolate exposure decreased classical indicators of fear. White noise suppressed sexual behaviors and caused avoidance of the open area. Yohimbine increased sexual receptivity during lavender exposure, decreased the latency to flee the white noise, and increased self-grooming regardless of the emotional challenge. Chlordiazepoxide was effective only during exposure to white noise, and increased the frequency of hiding alone. The modest effects of the drugs in the seminatural environment may be the result of social buffering and rats experiencing a high degree of controllability over their environment.

Demoxepam Derivatization and GC-MS Analysis Produces Erroneous Nordiazepam and Oxazepam Results.

Demoxepam, when derivatized by silylation and analyzed using gas chromatography-mass spectrometry (GC-MS), produces artifacts which are falsely identified as nordiazepam and oxazepam. Demoxepam was analyzed unextracted at various concentrations, using different derivatization procedures, and on different GC-MS systems. Oxazepam and nordiazepam were consistently identified in neat demoxepam samples, despite the changing variables. Under certain conditions, oxazepam was identified as low as 50 ng/mL derivatized demoxepam, and nordiazepam identified as low as 500 ng/mL derivatized demoxepam. The analysis of underivatized demoxepam resulted in nordiazepam detection at levels ≥2,500 ng/mL, whereas oxazepam was not detectable at or below 10,000 ng/mL demoxepam. Isolating the derivatization procedures and GC-MS analyses demonstrates that these processes are responsible for any degradation or rearrangement reactions which are taking place. Laboratories which follow similar procedures for benzodiazepine confirmations should consider these findings when interpreting analytical data from chlordiazepoxide cases.

Effects of plus-maze experience and chlordiazepoxide on anxiety-like behavior and serotonin neural activity in the dorsal raphe nucleus in rats.

The extent to which rats express anxiety-like behavior on the elevated plus-maze (EPM) depends on their previous maze experience. Open-arm avoidance develops in maze-experienced rats, and is often accompanied by a diminished anxiolytic response to benzodiazepines. Regions of the dorsal raphe nucleus (DRN) were examined in male Sprague-Dawley rats using c-Fos and serotonin immunohistochemistry following a single exposure, a second exposure or no exposure to the EPM. We then examined the effect of the benzodiazepine anxiolytic chlordiazepoxide (CDP, 5 mg/kg) on EPM behavior and DRN neural activity. Enhanced open-arm avoidance was evident on the second EPM trial in both experiments. The observed pattern of c-Fos expression suggests that the first exposure to the maze activates serotonin cells in the rostral and dorsal regions of the DRN and that only the dorsal subregion is activated by a second exposure. CDP increased open-arm exploration during the first trial, which corresponded to decreased 5-hydroxytryptamine (5-HT) activity in the rostral and ventral subregions of the DRN. However, 5-HT activity in the DRN was reduced in rats on the second maze trial compared with the first trial, when CDP had no effect on open-arm exploration. These results suggest that open-arm avoidance in maze-experienced rats can be characterized as a coping response that is mediated by specific populations of 5-HT neurons in the DRN.