ISSN:
1432-2013
Keywords:
l-Leucine
;
l-Glutamine
;
Pancreatic islets
;
Insulin release
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract l-Glutamine enhances insulin release evoked byl-leucine in isolated rat pancreatic islets. The enhancing action ofl-glutamine, which is a rapid but steadily increasing and not rapidly reversible phenomenon, is not attributable to any major change in either K+ or Ca2+ outflow from the islet cells. It coincides with an apparent increase in Ca2+ inflow rate and, hence, with Ca accumulation in the islets. The initial ionic response tol-leucine is not qualitatively altered by the presence ofl-glutamine. In their combined capacity to stimulate45Ca net uptake in the islets,l-glutamine can be replaced byl-asparagine but not byl-glutamate, whereasl-leucine can be replaced byl-norvaline orl-isoleucine, but not byl-valine, glycine orl-lysine. Such a specificity is identical to that characterizing the effect of these various amino acids upon insulin release. It is postulated that the release of insulin evoked by the combination ofl-leucine andl-glutamine involves essentially the same remodelling of ionic fluxes as that evoked by other nutrient secretagogues with, however, an unusual time course for the functional response tol-glutamine.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00657000
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