Characterization of receptors mediating AVP- and OT-induced glucagon release from the rat pancreas.
Am J Physiol
; 277(1): E56-62, 1999 07.
Article
en En
| MEDLINE
| ID: mdl-10409128
ABSTRACT
We characterized the receptors that mediate arginine vasopressin (AVP)- and oxytocin (OT)-induced glucagon release by use of a number of antagonists in the perfused rat pancreas and the fluorescence imaging of the receptors. AVP and OT (3 pM-3 nM) increased glucagon release in a concentration-dependent manner. The antagonist with potent V(1b) receptor-blocking activity, CL-4-84 (10 nM), abolished AVP (30 pM)-induced glucagon release but did not alter OT (30 pM)-induced glucagon release. d(CH(2))(5)[Tyr(Me)(2)]AVP (10 nM), a V(1a) receptor antagonist, and L-366,948 (10 nM), a highly specific OT-receptor antagonist, failed to inhibit AVP-induced glucagon release. In contrast, L-366,948 (10 nM) abolished OT (30 pM)-induced glucagon release but did not change the effect of AVP. Fluorescent microscopy of rat pancreatic sections showed that fluorescence-labeled AVP and OT bound to their receptors in the islets of Langerhans and that the bindings were inhibited by 1 microM of Cl-4-84 and L-366,948, respectively. Because AVP and OT at physiological concentrations (3-30 pM) increased glucagon release, we conclude that AVP and OT increase glucagon release under the physiological condition through the activation of V(1b) and OT receptors, respectively.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Páncreas
/
Arginina Vasopresina
/
Glucagón
/
Oxitocina
/
Receptores de Vasopresinas
/
Receptores de Oxitocina
Límite:
Animals
Idioma:
En
Revista:
Am J Physiol
Año:
1999
Tipo del documento:
Article
País de afiliación:
Estados Unidos