EN
Males and females of Wistar strain at different inbred level: 0, 25, 37, 50 and 100% have been examined 3 day starvation and 3h swimming has been applied. The control group have been given ether anaesthesia in order to collect blood samples. The level of growth hormone /GH/ in blood serum has been determined by RIA. Body weight has been measured and histological analysis of reticular layer of adrenal cortex has been made. The regression of GH concentration with the increase in the inbred level and the decrease in body weight has been found. It can be associated with higher resistance of females to acute stress and growing homozygosity compared to males.