Fine structure of gonadotrophs and prolactin producing cells in the rat pars distalis in organ culture.

A technique is described which permits the maintenance for up to 8 days in organ culture of explanted rat pituitary glands. Electron microscope studies showed that the cultured glands (whether treated with gonadotrophin-releasing hormone (GnRH) or not) were almost identical to controls in appearance, although the stellate (follicular) cells seemingly were eliminated in vitro. Gonadotrophs and prolactin-secreting cells in male and female pituitary glands were similar in appearance both in vivo and in vitro to comparable cells described by other authors. There was some evidence for an increase in the secretory activity of these cell types (particularly gonadotrophs) when the explants were treated with GnRH. The present technique thus provides a suitable and valid 'model' with which to study the effects of GnRH and steroid hormones on the release and synthesis of FSH and LH in vitro.