NICOTINE STIMULATES MATURATIONAL GONADOTROPIN (GTH2) RELEASE FROM CARP (CYPRINUS-CARPIO L) PITUITARY-CELLS

1. Perifusion of dispersed pituitary cells and pituitary cell culture was used to investigate the effects of cholinergic drugs on the secret ion of maturational gonadotropin (GtH2) in carp. 2. Nicotine strongly, and in a dose dependent manner, stimulated GtH2 release in male and i n female carp (from 10(-8) M in the perifusion and 10(-10) M in the ce lls cultures). 3. Nicotine is 10 times more active in females than in males. 4. The results suggest that in carp, nicotine stimulates GtH2 r elease directly from the pituitary cells, indicating a possible involv ement of a cholinergic system in the regulation of GtH2 secretion in t eleost fish.