Stress-induced immobility in male and female rats and its effects on offspring numbers, sex ratios and sexual hormones

Iman Rad,1,* Ehsan salarkia,2 Rashed sheikhzadeh,3

1. Kerman Physiology Research Center, Kerman University of Medical Sciences, Kerman, Iran
2. Kerman Physiology Research Center, Kerman University of Medical Sciences, Kerman, Iran
3. Department of Biology, Science and Research, Islamic Azad University

Abstract

Introduction

Stress-induced immobility inhibition of reproductive functions and can effect on sexual hormones. increasing/decreasing hormones affected by factors such as stress during developmental period causes discrepancy in stable effects on growth. the purpose of the present study was investigated the effects of repeated stationary stress on hormonal changes of ovary, testes and sexual ratio of neonates.

Methods

In this experimental study, 120 wistar rats, randomly divided in 4 groups, control, empirical group 1 (only females were under stress), empirical group 2 (only males were under stress) and empirical group 3 (both females and males were under stress). stress was applied by restrainer device to animals. after testing, 10 rats from each group were killed, sample bloods were collected from heart in order to measure hormonal changes of lh, fsh, testosterone, estrogen and progesterone via elisa method. then, the rats were divided into control and treatment group to measure number of neonates, their birth weights and their sexual ratio. results were analyzed by spss 20.

Results

Total number of neonates and male neonates reduced in empirical groups 2 and 3. significantly in comparison to control group. but number of female neonates in empirical group 2 increased. (p<0.05) weight of neonates, concentration of lh in female and fsh in male, estrogen and progesterone in empirical group reduced significantly in comparison to the control group. (p<0.05)

Conclusion

Result showed that, immobility stress can reduce sexual male and female hormones and also effect on birth of male neonates and the number alive born.

Keywords

Immobility stress, sexual female hormone, sexual male hormone, sexual ratio, rat