Repeated calcitonin treatment reduces the stimulation of inositol phospholipid by norepinephrine and serotonin in rat hippocampus and cerebral cortex.
Stimulation of inositol phospholipid hydrolysis by norepinephrine or 5-hydroxytryptamine was reduced in hippocampal or cortical slices from rats repeatedly injected with (Asu1.7)eel-calcitonin (2.5 IU/kg i.p.). This effect was specific, as the basal or carbamylcholine-stimulated inositol phospholipid hydrolysis was unchanged in slices from calcitonin-injected animals. The reduced responsiveness to norepinephrine did not reflect a decreased number or affinity of alpha 1-adrenergic recognition sites, suggesting that calcitonin treatment leads to a reduced coupling between alpha 1-adrenoceptors and phospholipase C.
Clementi
G
G
Institute of Pharmacology, University of Catania School of Medicine, Italy.
Favit
A
A
Curreri
R
R
Nicoletti
F
F
Scapagnini
U
U
D000818:Animals; D002116:Calcitonin / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology*; D010716:Phosphatidylinositols / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism*; D011224:Prazosin / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000494:pharmacology*
D010716:Phosphatidylinositols; D010743:Phospholipids; D012701:Serotonin; D002116:Calcitonin; D009638:Norepinephrine; D011224:Prazosin