Effect of age of donor on the responsiveness of dispersed and cultured chicken anterior pituitary cells to GnRH‐I

Abstract

1. The aim of this study was to devise a method to prepare and culture anterior pituitary cells from juvenile and adult chickens in order to investigate mechanisms controlling gonadotrophin‐releasing hormone‐I (GnRH‐I) ‐induced luteinising hormone (LH) release in vitro.

2. The optimum culture medium for maintaining gonadotroph responsiveness to GnRH‐I was bicarbonate‐buffered and phenol red‐free Medium 199 supplemented with 10% foetal calf serum.

3. Cultured pituitary cells from juvenile chickens were more responsive to GnRH‐I than cells from adult cockerels, while no LH was released in response to GnRH‐I from pituitary cells from laying hens.

4. Cultured pituitary cells from adult chickens of both sexes released LH in response to 12‐O‐tetradecanoyl‐13‐phorbol acetate (TPA), an activator of an enzyme involved in intracellular signalling, protein kinase C.

5. It is concluded that freshly‐dispersed and cultured gonadotrophs from adult chickens do not regain their responsiveness to GnRH‐I as well as freshly‐dispersed and cultured gonadotrophs from juvenile chickens. It appears that the stimulus‐secretion coupling pathway between the GnRH‐receptor and the activation of protein kinase C in gonadotrophs from adult chickens is more easily disrupted by dispersion and culture than in gonadotrophs from juvenile chickens.

Notes

Present address: Du Pont, Haskell Laboratory for Toxicology and Industrial Medicine, PO Box 50, Elkton Road, Newark, Delaware 19714–0050, USA

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