On the point of action for sympatho-adrenergic inhibition of duodenal alkaline secretion in the rat.
Experiments were performed on chloralose anaesthetized rats. A duodenal segment was decentralized by means of bilateral vagotomy and splanchnicotomy. The mucosal alkaline secretion by the segment was measured using an in situ pH-stat titration. The duodenal alkaline secretion was raised by about 100% utilizing two different secretagogues; vasoactive intestinal polypeptide (VIP) and prostaglandin E2 (PGE2). Direct splanchnic nerve stimulation (10 Hz, 5 min, bilaterally), or exogenous administration of the alpha-2-adrenoceptor agonist clonidine (15 micrograms h-1 kg-1), inhibited the secretion stimulated by PGE2, but not by VIP. The results suggest that the sympathetic nerves exert their inhibitory effect mainly on enteric secretomotor neurones.
Jönson
C
C
Department of Physiology, University of Göteborg, Sweden.
Johansson
B
B
Fändriks
L
L
D000818:Animals; D001639:Bicarbonates / Q000378:metabolism*; D001794:Blood Pressure; D003000:Clonidine / Q000494:pharmacology; D015232:Dinoprostone / Q000494:pharmacology; D004386:Duodenum / Q000187:drug effects / Q000294:innervation / Q000378:metabolism*; D004558:Electric Stimulation; D006863:Hydrogen-Ion Concentration; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013153:Splanchnic Nerves / Q000502:physiology; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000502:physiology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D001639:Bicarbonates; D014660:Vasoactive Intestinal Peptide; D015232:Dinoprostone; D003000:Clonidine