Reduced responses of prolactin and catecholamine to stress in the lactating rat.
Prolactin, GH, TSH, adrenaline and noradrenaline responses to the stress of immobilization were compared between lactating and non-lactating dioestrous rats. The concentrations of GH in plasma were reduced to a similar degree by the immobilization of lactating and non-lactating rats, and TSH levels were unchanged in both groups. The increases in plasma concentrations of adrenaline and noradrenaline induced by stress were significantly smaller in lactating than in non-lactating rats. Immobilization caused a marked increase in prolactin levels in the plasma of non-lactating rats but no increase in lactating rats. These changes may help to save energy and maintain milk production during the period of lactation.
Department of Physiology, Fukui Medical School, Japan.
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T
Higuchi
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H
Negoro
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Arita
D000818:Animals; D004837:Epinephrine / Q000097:blood*; D005260:Female; D013006:Growth Hormone / Q000097:blood; D007103:Immobilization; D007774:Lactation / Q000097:blood* / Q000523:psychology; D009638:Norepinephrine / Q000097:blood*; D011247:Pregnancy; D011388:Prolactin / Q000097:blood*; D051381:Rats; D011919:Rats, Inbred Strains; D013315:Stress, Psychological / Q000097:blood*; D013972:Thyrotropin / Q000097:blood
D011388:Prolactin; D013972:Thyrotropin; D013006:Growth Hormone; D009638:Norepinephrine; D004837:Epinephrine