Insulinotropic action of α-d-glucose pentaacetate: functional aspects.
نویسندگان
چکیده
The functional determinants of the insulinotropic action of α-d-glucose pentaacetate were investigated in rat pancreatic islets. The ester mimicked the effect of nutrient secretagogues by recruiting individual B cells into an active secretory state, stimulating proinsulin biosynthesis, inhibiting86Rb outflow, and augmenting45Ca efflux from prelabeled islets. The secretory response to the ester was suppressed in the absence of Ca2+ and potentiated by theophylline or cytochalasin B. The generation of acetate from the ester apparently played a small role in its insulinotropic action. Thus acetate, methyl acetate, ethyl acetate, α-d-galactose pentaacetate, and β-d-galactose pentaacetate all failed to stimulate insulin release. The secretory response to α-d-glucose pentaacetate was reproduced by β-d-glucose pentaacetate and, to a lesser extent, by β-l-glucose pentaacetate. It differed from that evoked by unesterifiedd-glucose by its resistance to 3- O-methyl-d-glucose,d-mannoheptulose, and 2-deoxy-d-glucose. It is concluded that the insulinotropic action of α-d-glucose pentaacetate, although linked to the generation of the hexose from its ester, entails a coupling mechanism that is not identical to that currently implied in the process of glucose-induced insulin release.
منابع مشابه
Insulinotropic action of a-D-glucose pentaacetate: functional aspects
WILLY J. MALAISSE, CARMEN SÁNCHEZ-SOTO, M. ELENA LARRIETA, MARCIA HIRIART, HASSAN JIJAKLI, CONCEPCIÓN VIÑAMBRES, MARÍA L. VILLANUEVA-PEÑACARRILLO, ISABEL VALVERDE, OLE KIRK, MARCEL M. KADIATA, AND ABDULLAH SENER Laboratory of Experimental Medicine, Brussels Free University, B-1070 Brussels, Belgium; Department of Biophysics, Institute of Cellular Physiology, Universidad Nacional Autónoma de Méx...
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ورودعنوان ژورنال:
- American journal of physiology. Endocrinology and metabolism
دوره 273 6 شماره
صفحات -
تاریخ انتشار 1997