EFFECT OF NICOTINE TREATMENT ON ANTERIOR-PITUITARY HORMONES IN MALE-RATS

We determined the effect of daily injections of nicotine on luteinisin g hormone (LH), thyroid stimulating hormone (TSH) and prolactin conten ts of the anterior pituitary gland, and on serum levels of these hormo nes. In the first study, groups of male rats (n = 12) received daily i njections of 0.312 mg or 1.25 mg of nicotine kg(-1) b.wt or saline 7 d ays. Treatment with 0.312 mg nicotine kg(-1) b.wt decreased anterior p ituitary gland LH, TSH and prolactin contents, but serum levels of the se hormones did not change. The higher dose of nicotine decreased seru m LH and TSH concentrations. In the second study, groups of male rats (n = 10) were injected daily with either 0.312 or 0.625 mg nicotine kg (-1) b.wt for 30 days. These doses did not effect the serum or pituita ry gland prolactin or serum LH concentrations. Both doses of nicotine reduced the anterior pituitary gland LH content significantly. These r esults indicate that chronic treatment with nicotine can alter hormone levels in the anterior pituitary gland.