title: The effect of atropine on secretin release and aspirated bicarbonate secretion after duodenal acidification in man.
abstract: The effect of duodenal instillation of hydrochloric acid on peripheral plasma immunoreactive secretin (IRS) concentration--without or with a constant intravenous infusion of atropine--was studied in eight healthy volunteers. Without atropine infusion, IRS increased from 1.2 +/- 0.3 pmol/l to a peak value of 17.1 +/- 4.4 pmol/l. The volume of duodenal aspirates increased from 0.74 +/- 0.12 ml/min to 5.03 +/- 0.46 ml/min, and the bicarbonate output from 7.6 +/- 1.7 mumol/min to 349 +/- 39 mumol/min. With atropine infusion (bolus of 500 micrograms + 750 micrograms/h of atropine sulphate), IRS increased from 1.4 +/- 0.3 pmol/l to 14.8 +/- 3.6 pmol/l. The volume of the duodenal aspirates increased from 0.71 +/- 0.08 ml/min to 2.76 +/- 0.37 ml/min and the bicarbonate output from 4.0 +/- 1.6 mumol/min to 142 +/- 33 mumol/min. The integrated IRS response to acidification was 18% lower during atropine infusion (p < 0.05). Both the aspirated flow rate from the duodenum and the bicarbonate output were markedly reduced by atropine infusion, 45% and 59%, respectively (p < 0.005).
mesh_terms: D000328:Adult; D001285:Atropine / Q000494:pharmacology*; D001639:Bicarbonates / Q000378:metabolism*; D004338:Drug Combinations; D004386:Duodenum / Q000378:metabolism*; D005260:Female; D006801:Humans; D006851:Hydrochloric Acid / Q000494:pharmacology; D008297:Male; D012633:Secretin / Q000097:blood / Q000378:metabolism*; D012636:Secretory Rate / Q000187:drug effects
chemical_list: D001639:Bicarbonates; D004338:Drug Combinations; D012633:Secretin; D001285:Atropine; D006851:Hydrochloric Acid