Role of central beta-adrenoceptors on stress-induced prolactin release in rats.
Adult Wistar male rats underwent immobilization stress (IS) during forty minutes. PRL secretion presented a remarkable increase after 5 minutes, and it was higher than pre-stress values during the entire duration of the experiment. The blockade of beta-1 adrenoceptors by icv injections of practolol did not modify IS-induced PRL release. IPS 339, a selective antagonist of beta-2 adrenoceptors, also injected icv, reduced PRL secretion during stress in a dose dependent fashion. The blockade of PRL secretion due to IPS 339 was reverted by a previous icv administration of salbutamol, a classical beta-2 agonist. The data presented here suggest that central beta-2 adrenoceptors activation is an important step in the control of stress-induced PRL secretion.
Department of Physiology, School of Medicine, University of São Paulo, Ribeirão Preto.
M A
MA
Haanwinckel
J
J
Antunes-Rodrigues
E
E
De Castro e Silva
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000420:Albuterol / Q000494:pharmacology; D000818:Animals; D008297:Male; D011217:Practolol / Q000494:pharmacology; D011388:Prolactin / Q000378:metabolism*; D011412:Propanolamines / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000502:physiology*; D012149:Restraint, Physical; D013312:Stress, Physiological / Q000209:etiology / Q000503:physiopathology*
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011943:Receptors, Adrenergic, beta; C014898:IPS 339; D011388:Prolactin; D000420:Albuterol; D011217:Practolol