DYNAMIC CHANGES IN PLASMA ADRENOCORTICOTROPHIN AFTER NEUROTROPIC STRESS IN MALE AND FEMALE RATS

Laboratoire de Physiologie des Régulations, Faculté des Sciences Biologiques, Avenue du Général Ledere, 35031 Rennes Cedex, France (Received 31 May 1977) Reports of the response of the hypothalamo-hypophysial-adrenal axis to stress have involved measurement of the levels of corticosterone and/or adrenocorticotrophin (ACTH) in the plasma of intact and adrenalectomized rats. It is known that the size and kinetics of the adrenal response are dependent on the nature of the stress and the sex of the rat (Kitay, 1961; Lescoat, Jego, Beraud & Maniey, 1970). From work on the effect of stress on plasma ACTH (Lutz, Koch & Miahle, 1969; Cook, Kendall, Greer, & Kramer 1973; Usategui, Oliver, Vaudry, Lombardi, Rosenberg & Mourre, 1976), the nature of the stress and the parameters of the response appear to be related and Barrett (1960) reported that the release of ACTH in response to stress is greater in female than in male rats. This