Dissimilar Anxiety-like Behavior in Prepubertal and Young Adult Female Rats on Acute Exposure to Aluminium

Background: Puberty is a developmental transition in which an estrogenic surge occurs, mediating the release of xenoestrogens, like aluminium. Aluminium’s effect on anxiety in rodents at the different developmental stages is inconsistent. Aims: This study aimed at investigating the effect of the metalloestrogenic property of aluminium on anxiety-like behavioral changes in prepubertal and young adult female rats. Objective: Considering this aim, our objective was to evaluate the anxiety-like behavior by the elevated plus maze in prepubertal and young adult female rats with or without acute exposure to aluminium. Methods: To address this property of aluminium, 5mg/Kg body weight (Al-5) and 10 mg/Kg body weight (Al-10) of aluminium was administered intraperitoneally to female rats at two developmental stages, prepubertal (PP; n = 8 for each dose) and young adult (YA; n = 6 for each dose) for two weeks. Post-treatment, three days behavioral assessment of the rats was done employing elevated plus maze. Results: Reduced escape latency was seen in Al-5, Al-10 pre-pubertal rats, and Al-5 young-adult rats on day 3. A significant reduction in open arm time was seen in the Al-5 young-adult rats. Aluminium treatment in the pre-pubertal rats reduced their head dipping and grooming. Reduced sniffing, head dipping, and stretch-attended posture in the treated young-adult female rats showed that they had impaired risk-taking tendency. Conclusion: Differential effect on the anxiety-like behavior in the pre-pubertal and young-adult female rats might be due to the metalloestrogenic property of aluminium, acting differently on the two age groups.

Effect of grewia hirsuta vahl ethanolic root extract on cognition in scopolamine induced amnesia

Objective Alzheimer's illnesses are becoming medical nightmares because there is no exact solution and existing nootropic medicines (Piracetam, tacrine, and metrifonate) have significant drawbacks. The goal of this study was to see if the ethanolic root extract of Grewia hirsuta (ERGH) could improve memory in rats who had been given scopolamine. Materials and procedures At rats, ERGH was given orally in dosages of 200 and 400 mg/kg for 28 days, followed by Scopolamine (18 mg/kg i.p.) from the 25th to the 27th day. The usual nootropic drug was piracetam (200 mg/kg). The elevated plus maze (EPM), Morris water maze (MWM), and passive avoidance (PA) paradigms are used to assess cognitive functioning. Invivo anti-oxidant activity and brain acetylcholine esterase (AchE) activity were assessed. Results: At the indicated doses, ERGH extract showed a substantial memory-enhancing activity by decreasing the transfer latency in EPM, increasing the escape latency in MWM, and increasing the shock-free zone in PA. In scopolamine-induced amnesia rats, pretreatment with ERGH resulted in a significant drop in AchE enzyme, an increase in enzymatic antioxidant, and a decrease in MDA levels. Conclusion Because of its several favorable benefits, such as memory-improving properties, anticholinesterase activity, and antioxidant activity, ERGH may prove to be a useful drug in the current study, and it would be important to investigate its potential in the care of Alzheimer's patients.

Studying some neuroprotective effects of Calotropis procera extracts against scopolamine- induced neuropschiatric comorbidities in a rodent model of epilepsy

Many plants are largely used in alternative medicine of Burkina Faso for neuropsychiatric disorders treatment. However, their neuro-pharmacological properties are less evaluated through scientific studies. The present study aims to evaluate the neuroprotective effect of Calotropis procera leaves and root-bark aqueous extract, focusing on a scopolamine-induced model of epilepsy in rodents. In this study, we evaluated this plant extracts possible protective effects on the central nervous system, through the behavioral tests and the enzymes activity assays. Thus, elevated plus-maze test and Y-maze task were used to evaluate animals behavioral and UV/visible spectrophotometer methods were used to evaluate the enzyme’s activities in brain’s supernatant. Our results are showing no significant protective effects of leaves extract, but it revealed a significant neuroprotective effect of root-bark aqueous extract, as well as in the behavioral tests and the brain’s oxidative enzymes specific activity evaluation. Indeed, anti-amnesic and anxiolytic activities were observed through Y maze task and elevated plus maze tests for the groups of animals receiving root-bark extract (100 mg/kg b.w.). In these test, inhibition of disturbances of Time spent in Open Arms, Spontaneous Alternation, and Transfer Latency induced after scopolamine administration were recorded with animals received root-bark extract. Likewise, the superoxide dismutase and catalase activity disturbance induced by scopolamine were also inhibited in root-bark extract pre-administered group. Thus, our study provides biochemical and neuro-pharmacological data for traditional use of C. procera for neuropsychiatric disorders treatment, including scopolamine-induced epilepsy symptoms (mainly referring to the psychiatric comorbidities of this disorder).

Evaluation of the neuroprotective activity of a new allylmorpholine derivative in a rat model of traumatic brain injury

Introduction. The search for and development of new drugs capable of reducing the severity of neurological deficit in traumatic brain injury are a critical task for investigational pharmacology. Chromone-containing allylmorpholines are a new group of neuroprotective drug candidates that have been shown to inhibit acetylcholinesterase and butyrylcholinesterase, and block N-methyl-D-aspartate receptors in vitro.Aim. This study aimed to evaluate the neuroprotective activity of the allylmorpholine derivative (E)-4-[3-(8-bromo-6-methyl-4-oxo-4H-chromen- 3-yl)-1-cyclohexylallyl]morpholin-4-ium chloride (33b) in vivo using a rat model of traumatic brain injury.Materials and methods. Traumatic brain injury was induced using the controlled cortical impact model. The allylmorpholine derivative was administered intraperitoneally at 1, 10, or 50 mg × kg-1 b.w. at 1 h after trauma induction, and then daily for the next 6 d. The neurological deficit was assessed using the Limb Placing, Open Field, Elevated Plus Maze, Beam Walking, and Cylinder tests.Results and discussion. At all doses administered, the allylmorpholine derivative had no positive effect on the motor function or exploratory behavior following traumatic brain injury. In the Elevated Plus Maze, 10 mg × kg-1 b.w. of the compound further suppressed exploratory behaviour in the injured animals, which appears to be consistent with its sedative properties observed previously in zebrafish.Conclusion. Despite the previously described in vitro affinity of allylmorpholines towards several molecular targets crucial for the pathogenesis of brain trauma and posttraumatic functional recovery, an allylmorpholine derivative had no neuroprotective effect in a rat model of traumatic brain injury in this study. These results further emphasize the importance of in vivo evaluation of potential neuroprotective drug candidates.

Systemic and intra-amygdala administrations of midazolam reverse anxiety-like behavior induced by cohabiting with a cagemate in chronic pain condition

The affective component of pain may be shared among conspecifics through emotional contagion, a form of empathic expression. In this sense, reverberation of negative emotions could generate distress behavioral responses, such as pathological anxiety. Evidences reported that amygdala and its benzodiazepine receptors are involved in perception of pain in others. However, relatively little is known about the neural processes underlying emotional contagion induced by pain observation. In the present study, we investigated the effects of midazolam, an allosteric GABAergic receptor agonist, in anxiety-like behaviors induced by cohabitation with cagemate submitted to sciatic nerve constriction. For this purpose, we administrated systemic (0.5, 1.0 and 2.0 mg/kg) and intra-amygdala midazolam injections (3.0 and 30.0 nmol) in observer cagemates before elevated plus-maze (EPM) evaluation. We found that mice subjected to nerve constriction and their observer cagemates increased anxiety-like behavior in the EPM. Further, systemically (1.0 and 2.0 mg/kg) and intra-amygdala administration of midazolam (3.0 and 30 nmol) reverse this anxiogenic effect. Collectively, these results suggest that social interaction with a cagemate under chronic pain produces anxiety-like responses that could be blocked through midazolam application.

TO EVALUATE THE EFFECT OF MORUS ALBA LEAVES EXTRACT ON SLEEP AND ANXIETY IN RAT MODELS

Objectives: The objectives of the study were to study the effect of Morus alba leaves extract (MAE) on sleep by phenobarbitone-induced sleeping time and the antianxiety effect by elevated plus maze apparatus model in rats. Methods: In this study, the effect of MAE on sleep was evaluated by the phenobarbitone-induced sleeping time of rats. The onset and the duration of sleep were recorded in minutes. The antianxiety effect was evaluated by the elevated plus maze apparatus model in rats. During 5 min test period, the number of entries into the open arm and closed arm and time spent in the open arm and closed arm were recorded in seconds. Results: MAE at the dose 200 and 400 mg/kg, highly significantly (p<0.001) decreased the onset of phenobarbitone-induced sleeping time. The duration of sleeping time was increased significantly (p<0.01) for 200 mg/kg and highly significantly (p<0.001) for 400 mg/kg as compared to the control group. M. alba has significant antianxiety activity in comparison with control in a dose-dependent manner. M. alba in a dose of 200 mg showed significant (p<0.01) and 400 mg/kg treated groups showed highly significant (p<0.001) anxiolytic activity by increasing the mean time spent in open arms as compared to control but less significant with standard (diazepam). Conclusion: Results indicate that the MAE has a significant dose-dependent effect on phenobarbitone- induced sleeping time and antianxiety effect in the elevated plus maze test.

Complex Interactions Between Sex and Stress on Heroin Seeking

Rationale: Stress plays a dual role in substance use disorders as a precursor to drug intake and a relapse precipitant. With heroin use at epidemic proportions in the United States, understanding interactions between stress disorders and opioid use disorder is vital and will aid in treatment of these frequently comorbid conditions.Objectives: Here, we combine assays of stress and contingent heroin self-administration (SA) to study behavioral adaptations in response to stress and heroin associated cues in male and female rats.Methods: Rats underwent acute restraint stress paired with an odor stimulus and heroin SA for subsequent analysis of stress and heroin cue reactivity. Lofexidine was administered during heroin SA and reinstatement testing to evaluate its therapeutic potential. Rats also underwent tests on the elevated plus maze, locomotor activity in a novel environment, and object recognition memory following stress and/or heroin.Results: A history of stress and heroin resulted in disrupted behavior on multiple levels. Stress rats avoided the stress conditioned stimulus and reinstated heroin seeking in response to it, with males reinstating to a greater extent than females. Lofexidine decreased heroin intake, reinstatement, and motor activity. Previous heroin exposure increased time spent in the closed arms of an elevated plus maze, activity in a round novel field, and resulted in object recognition memory deficits.Discussion: These studies report that a history of stress and heroin results in maladaptive coping strategies and suggests a need for future studies seeking to understand circuits recruited in this pathology and eventually help develop therapeutic approaches.

A Model in Female Rats With Phenotypic Features Similar to Interstitial Cystitis/Bladder Pain Syndrome

This report describes methodological and exploratory investigations of the zymosan-induced neonatal bladder inflammation (NBI) model of interstitial cystitis/bladder pain syndrome (IC/BPS) in female rats. These results validate and extend the currently employed model by evaluating critical timepoints for obtaining treatment effects and identified that a second insult as an adult including repeat intravesical zymosan, intravesical lipopolysaccharide, acute footshock stress, neuropathic nociception (facial) or somatic inflammation (hindpaw) all resulted in magnified visceromotor responses to urinary bladder distension (UBD) in rats which had experienced NBI when compared with their controls. NBI also resulted in increased tone and reactivity of pelvic floor musculature to UBD, as well as increased responsiveness to intravesical potassium chloride solutions, abnormal anxiety measures (elevated plus maze) and an increased number of submucosal petechial hemorrhages following 30 min of hydrodistension of the bladder. These phenotypic findings have correlates to the clinical features of IC/BPS in humans and so support use of this model system to examine mechanisms of and treatments for IC/BPS.

Effect of Short Time Exposure of Local ELF-MFs on Sleepiness Induced in Male Rats

Introduction: Lack of high-quality sleep causes serious side effects like anxiety and changes in plasma concentration of oxalate. The current study aimed to investigate the impact of local extremely low frequency magnetic fields (ELF-MFs) on inducing sleep (sleepiness) and anxiety in male rats. Methods: In this experimental study, 40 male rats were allocated in four groups (n=10). The ELF-MFs exposure (0, 10 and 18 Hz) was applied with intensity 200µT for three days (10 min/day). Sham-treated animal did not receive ELF-MF. Serum level of oxalic acid (OA) and sleepiness were measured both before first and after last exposure to ELF-MF or sham. Anxiety, sleepiness and OA were measured by using elevated plus maze, open-field test (OFT) and ELISA test, respectively. Results: Comparison of oxalate levels between before and after exposure to ELF-MF revealed that ELF-MF (10 Hz) decreased the serum level of oxalate (p<0.05). Comparison of the percent of open:closed arm entry (in elevated plus maze) between before and after exposure to ELF-MF revealed significant differences. Also, frequency, velocity and distance moved were decreased in the open-field test. Conclusion: Results of the present study demonstrated that ELF-MF with short time exposure may modulate the metabolism of OA and may modulate anxiety-like behavior or kind of induction of sleepiness in male rats.