Document Detail


Nitric oxide (NO) - Production and regulation of insulin secretion in islets of freely fed and fasted mice.
MedLine Citation:
PMID:  22120830     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
Production of nitric oxide through the action of nitric oxide synthase (NOS) has been detected in the islets of Langerhans. The inducible isoform of NOS (iNOS) is induced by cytokines and might contribute to the development of type-1 diabetes, while the constitutive isoform (cNOS) is thought to be implicated in the physiological regulation of insulin secretion. In the present study we have detected and quantified islet cNOS- and iNOS-derived NO production concomitant with measuring its influence on insulin secretion in the presence of different secretagogues: glucose, l-arginine, l-leucine and α-ketoisocaproic acid (KIC) both during fasting and freely fed conditions. In intact islets from freely fed mice both cNOS- and iNOS-activity was greatly increased by glucose (20mmol/l). Fasting induced islet iNOS activity at both physiological (7mmol/l) and high (20mmol/l) glucose concentrations. NOS blockade increased insulin secretion both during freely fed conditions and after fasting. l-arginine stimulated islet cNOS activity and did not affect islet iNOS activity. l-leucine or KIC, known to enter the TCA cycle without affecting glycolysis, did not affect either islet cNOS- or iNOS activity. Accordingly, insulin secretion stimulated by l-leucine or KIC was unaffected by addition of l-NAME both during feeding and fasting. We conclude that both high glucose concentrations and fasting increase islet total NO production (mostly iNOS derived) which inhibit insulin secretion. The insulin secretagogues l-leucine and KIC, which do not affect glycolysis, do not interfere with the islet NO-NOS system.
Authors:
Dag Eckersten; Ragnar Henningsson
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2011-11-24
Journal Detail:
Title:  Regulatory peptides     Volume:  -     ISSN:  1873-1686     ISO Abbreviation:  -     Publication Date:  2011 Nov 
Date Detail:
Created Date:  2011-11-28     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8100479     Medline TA:  Regul Pept     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
Copyright © 2011. Published by Elsevier B.V.
Affiliation:
Department of Nephrology and Transplantation Skane University Hospital, Sweden.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Low-dose ghrelin infusion - Evidence against a hormonal role in food intake.
Next Document:  Dexamethasone stimulates the expression of ghrelin and its receptor in rat hypothalamic 4B cells.