Pentagastrin-induced nitric oxide-dependent protein secretion from the parotid gland of the anaesthetized rat.
Infusion of pentagastrin (20 microg kg(-1) h(-1), i.v.) for 10 min evokes protein output but no overt fluid secretion from the parotid gland of the rat, as revealed by increased protein concentration in a subsequent wash-out flow of saliva in response to a bolus injection of methacholine (5 microg kg(-1), i.v.) 10 min later. Using this experimental set-up, the contribution of nitric oxide (NO) generation to the protein and amylase response evoked by pentagastrin was investigated. Neither the neuronal type NO synthase inhibitor N(omega)-propyl-L-arginine (N-PLA; 30 mg kg(-1), i.v.) nor the non-selective NO synthase inhibitor L-NAME (30 mg kg(-1), i.v.) as such affected the methacholine-evoked volume response or the outputs of protein and amylase. However, when preceeded by the pentagastrin infusion, the expected increases in concentrations of protein (145%) and amylase activity (127%) of the methacholine-evoked response (compared to a pre-infusion methacholine response) were reduced to 68 and 74%, respectively, in the presence of N-PLA, and to 70 and 63%, respectively, in the presence of L-NAME. Thus, NO generation resulting from the activity of the neuronal type NO synthase, most probably of parenchymal origin, plays an important role in the pentagastrin-induced protein and amylase secretion of the rat parotid gland.
Aras
Hülya Cevik
HC
Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at Göteborg University, Medicinaregatan 15 D, 405 30 Göteborg, Sweden.
Ekström
J
J
D000681:Amylases / Q000378:metabolism*; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D016210:Methacholine Chloride / Q000494:pharmacology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010306:Parotid Gland / Q000187:drug effects / Q000378:metabolism* / Q000503:physiopathology; D010418:Pentagastrin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012471:Salivary Proteins and Peptides / Q000378:metabolism*; D027544:Salvia / Q000378:metabolism; D014474:Unconsciousness / Q000503:physiopathology*
C511598:Bpifa2 protein, rat; D004791:Enzyme Inhibitors; C109599:N(omega)-propylarginine; D012471:Salivary Proteins and Peptides; D016210:Methacholine Chloride; D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase; D000681:Amylases; D010418:Pentagastrin; D019331:NG-Nitroarginine Methyl Ester