|
|
||||||||
Institute of Physiological Sciences, 1 Departments of Pharmacology and 2 Pathology, University of Lund, Lund, Sweden
Islet production of nitric oxide (NO) and CO in relation to islet hormone secretion was investigated in mice given the NO synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME) in their drinking water. In these mice, the total islet NO production was paradoxically increased, reflecting induction of inducible NOS (iNOS) in background of reduced activity and immunoreactivity of constitutive NOS (cNOS). Unexpectedly, normal mice fasted for 24 h also displayed iNOS activity, which was further increased in L-NAME-drinking mice. Glucose-stimulated insulin secretion in vitro and in vivo was increased in fasted but unaffected in fed mice after L-NAME drinking. Glucagon secretion was increased in vitro. Control islets incubated with different NOS inhibitors at 20 mM glucose displayed increased insulin release and decreased cNOS activity. These NOS inhibitors potentiated glucose-stimulated insulin release also from islets of L-NAME-drinking mice. In contrast, glucagon release was suppressed. In islets from L-NAME-drinking mice, cyclic nucleotides were upregulated, and forskolin-stimulated hormone release, CO production, and heme oxygenase (HO)-2 expression increased. In conclusion, chronic NOS blockade evoked iNOS-derived NO production in pancreatic islets and elicited compensatory mechanisms against the inhibitory action of NO on glucose-stimulated insulin release by inducing upregulation of the islet cAMP and HO-CO systems.
chronic nitric oxide synthase blockade; nitric oxide and carbon monoxide; insulin and glucagon secretion; isolated islets; cyclic nucleotides
This article has been cited by other articles:
![]() |
A. Vasilijevic, B. Buzadzic, A. Korac, V. Petrovic, A. Jankovic, and B. Korac Beneficial effects of L-arginine nitric oxide-producing pathway in rats treated with alloxan J. Physiol., November 1, 2007; 584(3): 921 - 933. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. S. Qader, J. Jimenez-Feltstrom, M. Ekelund, I. Lundquist, and A. Salehi Expression of islet inducible nitric oxide synthase and inhibition of glucose-stimulated insulin release after long-term lipid infusion in the rat is counteracted by PACAP27 Am J Physiol Endocrinol Metab, May 1, 2007; 292(5): E1447 - E1455. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Mosen, A. Salehi, R. Henningsson, and I. Lundquist Nitric oxide inhibits, and carbon monoxide activates, islet acid {alpha}-glucoside hydrolase activities in parallel with glucose-stimulated insulin secretion. J. Endocrinol., September 1, 2006; 190(3): 681 - 693. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Bertelli and M. Bendayan Association between Endocrine Pancreas and Ductal System. More than an Epiphenomenon of Endocrine Differentiation and Development? J. Histochem. Cytochem., September 1, 2005; 53(9): 1071 - 1086. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Salehi, S. S. Qader, E. Grapengiesser, and B. Hellman Inhibition of Purinoceptors Amplifies Glucose-Stimulated Insulin Release With Removal of its Pulsatility Diabetes, July 1, 2005; 54(7): 2126 - 2131. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Lundquist, P. Alm, A. Salehi, R. Henningsson, E. Grapengiesser, and B. Hellman Carbon monoxide stimulates insulin release and propagates Ca2+ signals between pancreatic {beta}-cells Am J Physiol Endocrinol Metab, November 1, 2003; 285(5): E1055 - E1063. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Henningsson, A. Salehi, and I. Lundquist Role of nitric oxide synthase isoforms in glucose-stimulated insulin release Am J Physiol Cell Physiol, July 1, 2002; 283(1): C296 - C304. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. NUNES, D. LEBREC, M. MAZMANIAN, F. CAPRON, J. HELLER, K. A. TAZI, E. ZERBIB, E. DULMET, R. MOREAU, A. T. DINH-XUAN, et al. Role of Nitric Oxide in Hepatopulmonary Syndrome in Cirrhotic Rats Am. J. Respir. Crit. Care Med., September 1, 2001; 164(5): 879 - 885. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |