Effect of exercise and morphine on psychological and physical dependencies, BDNF and TrkB gene expression in rat's hippocampus

Objectives: To compare the effect of exercise and morphine on abstinence syndrome and hippocampal gene expression in rat model

Methods: Thirty adult male rats were exposed to voluntary wheel exercise [low, medium, high] for 28 days. The subjects entered Conditioned Place Preference [CPP] apparatus and experienced morphine [low, medium, high] CPP and followed by naloxone test. Correlation between exercise level, morphine injection, concurrent morphine administration and exercise with morphine CPP, BDNF and TrkB genes was determined. Rats were euthanized, decapitated and the hippocampus was removed. The expression of BDNF and TrkB genes were evaluated by real time PCR

Results: Active rats ran an average of 839.18 m/d. A significant [P<0.001] correlation between exercise level, morphine injection, concurrent morphine administration and exercise with morphine CPP and BDNF and TrKB gene expressions was found

Conclusion: Voluntary exercise in different levels potentiates the brain rewarding system, CPP scale, and hippocampal BDNF and TrKB expressions. High range of voluntary exercise demonstrated an increase in the likelihood of developing addictive and drug-seeking behavior

Histopathologic and sonographic analysis of laparoscopic removal ovarian nonendometriotic cyst: the evaluating effects on ovarian reserve

Currently, laparoscopic cystectomy is the first-line therapy for ovarian benign cysts that are resistant to current therapies. There are different studies that point to ovarian reserve damage due to laparoscopic cystectomy. In this study, we evaluate the ovarian damage following laparoscopic cystectomy for non-endometriosis cysts using ultrasound and pathology findings. This is a prospective cohort study conducted between 7rd month of 2011 and 10th month of 2012 in Women hospital affiliated to Tehran university of medical sciences.45 non-endometriosis cysts [17 teratoma,7 mucinous, 10 simple serous and 11 simple cysts] underwent laparoscopic cystectomy with stripping technique. Amount of excised parenchyma, number of lost oocytes and cyst wall fibrosis thickness were histopathologically studied. Before and 3 months after surgery antral follicle count was evaluated by ultrasound. AFC after cystectomy for teratoma and simple serous was significantly reduced P<0.05. By larger teratomas and more parenchyma inadvertently removed during their excision [1.64, 0.255] reduced AFC was seen and in simple serous cysts with more removed parenchyma amount [1.5] reduced AFC occurred. In our study simple cysts excision led to a loss in AFC that was not associated with any other cyst parameters. Mucinous cysts resection led to no specific ovarian reserve damage. Laparoscopic cystectomy for non-endometriosis leads to reduced ovarian reserve

A role for endocannabinoids in acute stress-induced suppression of the hypothalamic-pituitary-gonadal axis in male rats / 대한생식의학회지

OBJECTIVE: Stress is known to be an inhibitor of the reproductive hypothalamic-pituitary-gonadal (HPG) axis. However, the neural and molecular connections between stress and reproduction are not yet understood. It is well established that in both humans and rodents, kisspeptin (encoded by the kiss1 gene) is a strong stimulator of the HPG axis. In the present study we hypothesized that endocannabinoids, an important neuromodulatory system in the brain, can act on the HPG axis at the level of kiss1 expression to inhibit reproductive function under stress. METHODS: Adult male Wistar rats were unilaterally implanted with an intracerebroventricular cannula. Afterwards, the animals were exposed to immobilization stress, with or without the presence of the cannabinoid CB1 receptor antagonist AM251 (1 microg/rat). Blood samples were collected through a retro-orbital plexus puncture before and after stress. Five hours after the stress, brain tissue was collected for reverse transcriptase-quantitative polymerase chain reaction measurements of kiss1 mRNA. RESULTS: Immobilization stress (1 hour) resulted in a decrease in the serum luteinizing hormone concentration. Additionally, kiss1 gene expression was decreased in key hypothalamic nuclei that regulate gonadotrophin secretion, the medial preoptic area (mPOA), and to some extent the arcuate nucleus (ARC). A single central administration of AM251 was effective in blocking these inhibitory responses. CONCLUSION: These findings suggest that endocannabinoids mediate, at least in part, immobilization stress-induced inhibition of the reproductive system. Our data suggest that the connection between immobilization stress and the HPG axis is kiss1 expression in the mPOA rather than the ARC.

Effects of lithium on peripheral neuropathy induced by vincristine in rats

Vincristine [VCR] as a frequently used antimitotic agent which is commonly prescribed for wide spectrum of neoplasm, causes mixed sensorimotor neuropathy. Several evidences show lithium could be a neuroprotective agent, therefore to assess whether a pretreatment and at subtherapeutic dose it could prevent the peripheral neuropathy produced by VCR, rats were treated with VCR 0.1mg/kg i.p. for 3 alternative doses and / or lithium chloride [20mg/kg or 40 mg/kg i.p. daily from the first day to the day of sacrifice]. Erythrocyte lithium concentration [ELC] and plasma lithium concentration [PLC] were measured at the seventh day of study and the day of scarification. After seventh day of lithium administration, PLC and ELC reached to a steady state at subtherapeutic dose and they did not significantly change at normal housing situation. Hot plate, open field test and nerve conduction velocity were used to evaluate the sensory and motor neuropathy. Only VCR treated rats showed behavioral, electrophysiological and histological evidences of a mixed sensorimotor neuropathy by significant increase in hot plate latencies and a marked decrease in total distance moved and conduction velocities in both sensory and motor nerves. Lithium at the dose of 20mg/kg and specially 40mg/kg robustly reduced the rate of mortality, general toxicity and was able to ameliorate mixed sensorimotor neuropathy induced by VCR. These results suggest that lithium at dose of 20mg/kg and 40 mg/kg, potentially by its effects on cell survival pathways such as inhibition of glycogen synthase kinase-3 [GSK3beta], can prevent both motor and sensory components of VCR neuropathy

Medical students' viewpoint regarding the integrated module of basal ganglia

Integration is an important educational strategy in medical education. Considering this idea, the goal of the present study was to design and implementation of longitudinal and vertical integrated education of anatomy, physiology, pharmacology, neurology and neuropsychiatry subjects of brain's basal ganglia by a multidisciplinary team. Kern's approach to curriculum development was used. Participants were 20 medical students at basic science level who contribute in a 10 stations of pre-test exam at Medical School's Skill Lab. After the implementation of the module by a multidisciplinary team, post-test were done. A structured questionnaire was designed to assess student opinions about adequacy, usefulness of the module using a Likert scale with 5 categories ranging from "completely agreement" to "completely disagreement". The result of pre and post-test were also compared. Twenty questionnaires were completed, giving a 77.63% satisfaction rate. Seventy-five percent of students found it useful and appropriate at basic science level. About fifty percent of students suggested the implementation of this module for other medical students. The score of post-test was significantly [14.52 +/- 0.47 vs 6.32 +/- 0.62, P<0.05] higher than pre-test results. The viewpoints of medical students were positive and they value the module highly. Since it is not easy to change the style we teach, these results suggest necessitate of supporting the faculty member's participation in these modules