Effect of sexual steroids upon ontogeny of alpha-amylase of rat parotid gland.

The effect of gonadectomy (at the 10th day of life) and treatment with sexual steroids (during the first month) upon development of alpha-amylase activity in rat parotid gland has been studied. Alpha-amylase specific activity of parotid glands from 20-day-old orchidectomized rats and from 25-day-old ovariectomized animals was significantly higher than that of intact male and female rats of the same age respectively. Spayed males treated with testosterone (10 microgram/day on the 13th, 15th, and 17th day) and ovariectomized rats treated with oestradiol (2.5 microgram/day from the 16th to the 22nd day) showed values of enzymic activity similar to those of normal animals. Results indicate that oestradiol and testosterone have an inhibitory effect upon the increase of alpha-amylase activity in parotid gland during a very defined period of development.