Effects of lorglumide and atropine on MgSO(4)-induced gallbladder emptying in conscious dogs.
The aim of the study was to examine the possible involvement of cholecystokinin (by lorglumide) and cholinergic mechanisms (by atropine) in magnesium sulphate (MgSO(4))-induced gallbladder contraction of conscious dogs. The gallbladder (GB) volume was determined by ultrasonography. The optimal dose of 80 mg kg(-1)of MgSO(4)was determined from a MgSO(4)dose-response curve using doses of 10, 20,40, 80, 120 mg kg(-1). The largest dose of MgSO(4)was less effective than the optimal dose. Peak gallbladder contraction (32 per cent) was achieved at 30 minutes. Atropine (50 microg kg(-1)s.c.) or lorglumide (1 mg kg(-1)p.o.) fully prevented GB contraction. In conclusion, supraoptimal doses of MgSO(4)have a diminishing effect. The sustained contraction of the gallbladder in response to the optimal dose of MgSO(4)can be explained by an additive effect of the cholecystokinin release and a cholinergic trigger mechanism. Ultrasonography and MgSO(4)stimulation proved to be a valuable technique for examination of gallbladder motility.
Sterczer
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A
Department of Internal Medicine, AOTE, University of Veterinary Science, Budapest, Hungary. astercz@ns.univet.hu
Szénási
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G
Vörös
K
K
Pap
A
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D000818:Animals; D001285:Atropine / Q000494:pharmacology*; D002766:Cholecystokinin / Q000502:physiology; D004285:Dogs / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D005704:Gallbladder / Q000000981:diagnostic imaging / Q000187:drug effects*; D006727:Hormone Antagonists / Q000494:pharmacology*; D008278:Magnesium Sulfate / Q000008:administration & dosage / Q000494:pharmacology*; D008747:Methylcellulose / Q000494:pharmacology; D018727:Muscarinic Antagonists / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D011377:Proglumide / Q000031:analogs & derivatives* / Q000494:pharmacology; D014463:Ultrasonography
D006727:Hormone Antagonists; D018727:Muscarinic Antagonists; D008278:Magnesium Sulfate; D001285:Atropine; D008747:Methylcellulose; D002766:Cholecystokinin; D011377:Proglumide; C048181:lorglumide