Activity of steroid sulphatase and estrogen sulphotransferase in the boar epididymis during the postpubertal period

The activities of steroid sulphatase (StS) and estrogen sulphotransferase (EST) were determined in the epididymis of 18 boars. The animals were divided into three groups (n = 6) according to age (8, 12 and 16 months). The boars were anesthetized and castrated. The tissue samples of different epididymal parts (caput, corpus and cauda) were taken and homogenized. Activities of StS and EST were assessed using 3H-estrone sulphate (3H-E1S) and free 3H-oestrone (3H-E1) as substrates, respectively. The substrate conversion rates after 60 min of incubation were 51.25% for 3H-E1S and 45.65% for 3H-E1. The activities of both enzymes were significantly higher in the caput epididymis compared to the cauda epididymis (p < 0.05). A significant age-dependent increase of StS and EST activities (p < 0.05) was observed. These results suggest that the availability of estrogens in the boar epididymis may be locally controlled also by StS and EST. The age-dependent increase of StS and EST activities may be related to the process of “biochemical maturation” of the reproductive system during the postpubertal period.