A role for the area postrema in mediating cholecystokinin-stimulated oxytocin secretion.
We have investigated the role of the area postrema (AP) in mediating the neurohypophyseal hormone response to peripheral administration of nausea-producing agents in rats. In control animals, lithium chloride (LiCl) and apomorphine (APO) caused a rise in plasma levels of immunoreactive oxytocin (OT) and arginine-vasopressin (AVP), whereas sulphated cholecystokinin octapeptide (CCK-8s) stimulated OT secretion only. Rats with AP lesions exhibited a similar OT and AVP response to LiCl and APO but the OT response to CCK-8s was significantly diminished. The results indicate that the selective stimulation of OT secretion by CCK-8s is partly mediated via the AP. Although the nausea-producing effects of LiCl and APO may involve the AP, the neuroendocrine effects of these agents may well be mediated via actions outside the AP.
Carter
D A
DA
Medical Unit, Charing Cross and Westminster Medical School, Westminster Hospital, London, U.K.
Lightman
S L
SL
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001127:Arginine Vasopressin / Q000097:blood / Q000378:metabolism; D001835:Body Weight; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D002712:Chlorides / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology; D018021:Lithium Chloride; D008297:Male; D010121:Oxytocin / Q000097:blood / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012844:Sincalide / Q000494:pharmacology*
D002712:Chlorides; D001127:Arginine Vasopressin; D010121:Oxytocin; D008094:Lithium; D018021:Lithium Chloride; D012844:Sincalide; D001058:Apomorphine