Primary culture of normal pituitary cells of carp (Cyprinus carpio) for the study of gonadotropin release

A method for preparing enzymatically dispersed pituitary cell cultures of carp (Cyprinus carpio) is described. The cultures have been used to assay a synthetic analog of gonadotropin releasing hormone (GnRH) and to determine the specificity of steroids able to affect gonadotropin (GtH) release in vitro. Time course secretion studies indicated that by 48 h incubation, in the presence of 500 pM GnRH, cumulative secretion of gonadotropin ($719 ng \pm 90/2.5 \times 10^{5} cells$) had exceeded that of controls ($446 ng \pm 106/2.5 \times 10^5$cells).$Estradiol-17\beta$, progesterone, testosterone, and 11-ketotestosterone showed different inhibitory effects on pituitary basal GtH release. Based on the results, it was concluded that carp pituitary cell cultures can be applied to investigations of several aspects of the hypothalamo-hypophysial-gonadal system.