The role of hippocampal 5-HT1D and 5-HT1F receptors on learning and memory in rats.

Serotonin is a neurotransmitter, which is involved in memory via its receptors. The 5-HT1D and 5-HT1F receptors mainly exist in the hippocampus, which plays an important role in memory processing. However, few studies have assessed the effect of these serotonin receptors on memory. We evaluated the effect of a 5-HT1D receptor agonist, PNU142633, 5-HT1D receptor antagonist, BRL15572 hydrochloride, and 5-HT1F receptor agonist, LY344864, on the recognition and avoidance memory in the hippocampus area. Fifty adult male Wistar rats weighing 200-250 g were divided into the control, sham-operated, PNU, BRL, and LY groups (n=10 per group). Bilateral guide cannulas were implanted into the dentate gyrus area of the hippocampus. The drugs were administered at the dose of 1 µg/µl before the novel object recognition (NOR) and passive avoidance learning (PAL) tests. The results showed that in the NOR test, the administration of PNU and LY had no significant effect on recognition index; however, the recognition index was increased by BRL. In the PAL test, the administration of PNU had no significant effect on recognition index, but the administration of BRL and LY increased the time spent in the dark compartment of the apparatus and decreased the step-through latency into the dark compartment apparatus. It can be concluded that the inhibition of the hippocampal 5-HT1D receptor improved cognition memory but impaired avoidance memory. Activation of the hippocampal 5-HT1F receptor had no effect on cognitive memory but impaired avoidance memory.

Structural model of the relationship between physical activity and students' quality of life: Mediating role of body mass index and moderating role of gender.

BACKGROUND: As a country's future leaders and pioneers, University students must live with healthy habits. In order to achieve a healthy lifestyle, Physical activity and Quality of Life can serve as suitable indices to study. The purpose of the study was to clarify how physical activity (PA), Body mass index (BMI) and gender relate to the quality of life (QOL) of students of Medical Sciences University by using a structural equation model. METHODS: The research was a cross-sectional study. The number of participants was 225 students of the University. The participants answered three questionnaires, including Demographic, International Physical Activity Questionnaire (IPAQ short form), and Quality of Life Questionnaire (SF-12), BMI was calculated by anthropometric measures, as well. The Structural equation model (SEM) method was employed. The Fitness of the proposed pattern was measured using the following indexes: chi-square/degree of freedom ratio (CMIN/DF), Normed Fit Index (NFI), comparative fit index (CFI), the goodness of fit index (GFI), and standardized root mean squared residual (SRMR). In the analysis the significant level was considered as P < 0.05. RESULTS: PA (r = -0.726, P<0.001) and QOL (r = -0.405, P<0.001) have significantly inverse relationship with BMI, whereas the QOL and PA were proven to be positively related (r = 0.357, P<0.001). Moreover, the results signify gender as a moderator in the relationship between PA and QOL (Δχ2 (10) = 19.903, P = 0.030) and also the mediatory role of BMI among students. BMI affects the QOL in men (P < 0.001, ß = -0.307) more in compare to women women (P = 0.324, ß = -0.158). CONCLUSION: Study findings supported the research hypothesis. Gender exhibited moderating role in the relationship between PA and QOL, considering the mediating role of BMI.