Hormone Levels of Anterior Pituitary Gland and Serum in Nagase Analbuminemia Rats

Abstract

The hormone levels in the anterior pituitary gland and serum in Nagase analbuminemia rats (NAR), a mutant strain established from Sprague-Dawley rats with hyperlipidemia, were examined. For the anterior pituitary gland, the prolactin, TSH, GH, LH and FSH contents in male NAR were significantly lower than those of normal rats. In female NAR, prolactin, TSH and LH levels were also lower than those in normal rats, whereas FSH and GH were normal. For the serum, the concentrations of TSH, total T3, total and free T4, estradio1-17β and testosterone were examined. The serum testosterone concentration in NAR was lower than that of normal rats. Histochemical examination of the hydroxysteroid dehydrogenase (HSD) activity of testes was made in relation to the serum testosterone level. NAR testes, which are rather small compared with those of normal rats, have lower HSD activity. A higher level of serum TSH was seen in NAR. Total and free T4 concentrations were low in the male NAR only. Estradiol-17β and T3 concentrations in NAR were unchanged. Changes in serum LH and FSH levels during the estrous cycle in NAR were also studied. Their patterns of change are normal.