Ethanol causes mucosal injury to the stomach and which accompanied by back-diffusion of H+. Using several drugs known to modify the gastric acid secretion and to provide cytoprotection the effect of back-diffusion of H+ by ethanol was examined. Following 48 hours of starvation rats were anesthetized with urethane, and their stomachs were filled with 4 ml of 20% ethanol solution containing 1.8 mM HCI (7.2 microEq/4 ml) every 15 min. H+ content of the collected perfusates was determined by back-titration to pH 6.0. The presence of ethanol in the stomach for 1 hour caused a loss of luminal H+ at a rate of 4.8 +/- 0.4 microEq/15 min. Pretreatment of rats with atropine (2 mg/Kg, i.v.), pirenzepine(2 mg/Kg. i.v.), cimetidine (10mg/Kg i.v.), cromolyn sodium (20mg/Kg/hr, i.v.) or domperidone (1 mg/kg. i.v.) did not affect the ethanol-induced H+ back-diffusion. Similarly, no effect was seen in rats treated with prostaglandin E2 (100 microgram/Kg i.v.) or indomethacin (5 mg/Kg, s.c). The addition of procaine (10(-5)~10(-3) M) or propranolol (10(-9)~10(-5) M) to the perfusate did not cause any changes in the ethanolinduced H+ back-diffusion. However, pretreatment of rats with acetazolamide (100 mg/Kg i.v.) or ethoxzolamide(50 mg/Kg/day, p.o. for 6 days), carbonic anhydrase inhibitors, markedly suppressed the ethanol-induced loss of luminal H+. Based on these results, it is suggested that ethanol-induced back-diffusion of H+ is mediated, at least in part, by the activity of carbonic anhydrase, and that cholinergic, histaminergic and dopaminergic mechanisms are not involved. Moreover, the implications of prostaglandins and membrane stability are not suggested.
Absorption ; Animal ; Diffusion ; Ethanol/pharmacology* ; Female ; Gastric Acid/secretion* ; Gastric Mucosa/drug effects* ; Male ; Parasympatholytics/pharmacology ; Protons* ; Rats

OBJECTIVETo compare the relief effect of diltiazem, papaverine and nitroglycerin on radial artery spasm in elderly patients with coronary atherosclerotic heart disease.

METHODSSixty patients aged beyond 70 years underwent coronary artery bypass grafting (CABG) with autologous radial artery from July 2009 to March 2010. Redundant radial artery was collected and the relief function of different drugs was evaluated through "organ bath" technique in vitro. All the patients were randomly divided into 3 groups based on different antispasmodic drugs: diltiazem, papaverine and nitroglycerin. Thirty seconds free blood flow of radial artery and hemodynamic parameters (heart rate, mean arterial pressure and central venous pressure) were assessed before and after intra-radial administration of diltiazem, papaverine and nitroglycerin in vivo.

RESULTSAll three drugs could relieve radial artery spasm in different levels and the eventual relief rate was over 80%. Only nitroglycerin could relax radial artery completely, the relief capacity of nitroglycerin, diltiazem and papaverine decreased in order. There was no significant difference in the hemodynamic parameters before and after the injection. Blood flow of radial artery increased in nitroglycerin group [(42 ± 10) ml/30 s vs. (28 ± 7) ml/30 s, P < 0.05] while there was no significant difference in diltiazem [(23 ± 10) ml/30 s vs. (25 ± 8) ml/30 s, P > 0.05] and papaverine group [(25 ± 10) ml/30 s vs. (24 ± 9), P > 0.05].

CONCLUSIONSNitroglycerin could relieve vasospasm of radial artery effectively and increased blood flow. Nitroglycerin is the suitable antispasmodic drug for radial artery in the elderly patients with coronary atherosclerotic heart disease compare with diltiazem and papaverine.

Aged ; Aged, 80 and over ; Coronary Artery Bypass ; Coronary Artery Disease ; physiopathology ; surgery ; Diltiazem ; pharmacology ; Female ; Follow-Up Studies ; Humans ; Male ; Nitroglycerin ; pharmacology ; Papaverine ; pharmacology ; Parasympatholytics ; pharmacology ; Radial Artery ; drug effects ; physiology ; transplantation