Please use this identifier to cite or link to this item: http://ahro.austin.org.au/austinjspui/handle/1/11252
Title: Effects of nitric oxide synthase blockade on dorsal vagal stimulation-induced pancreatic insulin secretion.
Authors: Mussa, Bashair M;Sartor, Daniela M;Rantzau, Christian;Verberne, Anthony J M
Affiliation: Department of Medicine, University of Melbourne, Austin Health, Heidelberg 3084, Victoria, Australia.
Issue Date: 16-Apr-2011
Citation: Brain Research 2011; 1394(): 62-70
Abstract: We and others have previously shown that the dorsal motor nucleus of the vagus (DMV) is involved in regulation of pancreatic exocrine secretion. Many pancreatic preganglionic neurons within the DMV are inhibited by pancreatic secretagogues suggesting that an inhibitory pathway may participate in the control of pancreatic exocrine secretion. Accordingly, the present study examined whether chemical stimulation of the DMV activates the endocrine pancreas and whether an inhibitory pathway is involved in this response. All experiments were conducted in overnight fasted isoflurane/urethane-anesthetized Sprague Dawley rats. Activation of the DMV by bilateral microinjection of bicuculline methiodide (BIM, GABA(A) receptor antagonist, 100 pmol/25 nl; 4 mM) resulted in a significant and rapid increase in glucose-induced insulin secretion (9.2±0.1 ng/ml peak response) compared to control microinjection (4.0±0.6 ng/ml). Activation of glucose-induced insulin secretion by chemical stimulation of the DMV was inhibited (2.1±1.1 ng/ml and 1.6±0.1 ng/ml 5 min later) in the presence of the muscarinic receptor antagonist atropine methonitrate (100 μg/kg/min, i.v.). On the other hand, the nitric oxide (NO) synthesis inhibitor l-nitroarginine methyl ester (30 mg/kg, i.v.) significantly increased the excitatory effect of DMV stimulation on glucose-induced insulin secretion to 15.3±3.0 ng/ml and 16.1±3.1 ng/ml 5 min later. These findings suggest that NO may play an inhibitory role in the central regulation of insulin secretion.
Internal ID Number: 21530944
URI: http://ahro.austin.org.au/austinjspui/handle/1/11252
DOI: 10.1016/j.brainres.2011.04.015
URL: http://www.ncbi.nlm.nih.gov/pubmed/21530944
Type: Journal Article
Subjects: Animals
Atropine Derivatives.administration & dosage
Bicuculline.administration & dosage.analogs & derivatives
Enzyme Inhibitors.administration & dosage
GABA-A Receptor Antagonists.administration & dosage
Injections, Intraventricular
Insulin.secretion
Male
Medulla Oblongata.drug effects.metabolism
Microinjections
NG-Nitroarginine Methyl Ester.administration & dosage
Neural Pathways.drug effects.metabolism
Nitric Oxide.metabolism
Nitric Oxide Synthase.antagonists & inhibitors
Pancreas.innervation.secretion
Parasympatholytics.administration & dosage
Rats
Rats, Sprague-Dawley
Vagus Nerve.physiology
Appears in Collections:Journal articles

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