Application of an in-vitro perifusion technique to studies of luteinizing hormone release by rat anterior hemi-pituitaries: Self-potentiation by luteinizing hormone releasing hormone.
A technique is described for the continuous perifusion of rat adenophypophyses. Exposure of the perifused glands to repeated equal 5 min stimuli with hypothalamic extract resulted in a series of equal peaks of corticotrophin secretion, the response was proportional to log dose over the range 0 - 25-2 - 0 rat hypothalamic equivalents/ml. Repeated equal stimuli with hypothalamic extract, or with luteinizing hormone releasing hormone (LH-RH) at concentrations of 2 or 10 ng/ml, resulted in a progressively increasing series of peaks of LH secretion, i.e. a self-potentiating or priming effect. The effect took between 30 min and 1 h to develop. A delayed increase in the responsiveness of the glands was also seen with continuous incubation of anterior pituitaries with LH-RH. The relevance of these observations to the physiological control of LH secretion is discussed.
D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D007986:Luteinizing Hormone / Q000378:metabolism*; D010477:Perfusion / Q000379:methods; D010902:Pituitary Gland / Q000378:metabolism*; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D012636:Secretory Rate / Q000187:drug effects
D000324:Adrenocorticotropic Hormone; D007986:Luteinizing Hormone