Investigation of the effects of heat and cold stress on the gonadotrophins and sex steroids in rats [Ratlarda sicak ve soguk stresi?ni?n gonadotropi?nler ve seks steroi?dleri? üzeri?ne etki?leri?ni?n araştirilmasi]

Abstract

Purpose: This study aims to evaluate the effects of the heat and cold stress on the levels of gonadotrophins (FSH, LH) and sex steroids (estradiol, testosterone) in rats. Material and methods: Male and female rats were grouped as control group(7 rats) and stress group (7 rats). Vaginal smears were taken daily from the control and test groups of female rats in the proestrus stage. Heat (40 ?C) and cold (4 ?C) stress was applied to the stress group for one hour and then blood samples taken from the heart. Serum FSH, LH, estradiol and testosterone levels were measured by RIA. The results were statistically evaluated by Kruskal-Wallis and Mann-Whitney U tests. Results: There were not statiscally significant changes in the FSH, LH and estradiol level of female rats (P>O.05). Statistically significant changes in the testosterone (T) level of male rats were observed (P<0.05), but there were not significant changes in FSH and LH levels (P<0.05). When the testosterone levels of the groups were correlated, statistically significant differences between the control and the heat applied group was observed (P<0.05); there was not a significant difference between the control and the cold applied group (P>0.05). Conclusion: Various patterns of stress can cause different hormonal responses in male and female rats. Variations in the type of stress (acute or chronic), experimental conditions, experimental animals and psychological influences can affect the response to stress in experimental settings.