Cardiovascular and bronchial actions of famotidine in anesthetized dogs.
The effects of famotidine (Gaster; CAS 76824-35-6) and cimetidine on cardiovascular and bronchial functions were investigated in anesthetized dogs. Famotidine did not affect heart rate, blood pressure, left ventricular pressure (LVP), max. dLVP/dt, cardiac output or coronary blood flow at i.v. doses of 1 to 30 mg/kg in open-chest dogs anesthetized with pentobarbital or a combination of nitrous oxide, oxygen and halothane (GOF). No hemodynamic changes were either observed after famotidine in pentobarbital anesthetized dogs whose cardiac function was depressed by propranolol (1 mg/kg i.v.). On the contrary, cimetidine dose-dependently decreased heart rate and blood pressure at doses greater than 3 mg/kg, and left ventricular pressure, cardiac output and coronary blood flow at the dose of 30 mg/kg. Regarding the electrocardiogram (ECG), famotidine did not produce any remarkable change at doses up to 30 mg/kg with the exception of a transient increase or decrease in the T-wave amplitude at a dose of 30 mg/kg. Cimetidine prolonged Q-T intervals of ECG in addition to changing the T-wave at a dose of 30 mg/kg. Neither famotidine nor cimetidine showed any effect on resting and histamine-increased bronchoresistance at doses up to 30 mg/kg. It is concluded that famotidine is superior to cimetidine with regard to safety because famotidine has no significant effects on cardiovascular functions in anesthetized dogs.
Miyata
K
K
Department of Pharmacology, Medicinal Research Laboratories, Yamanouchi Pharmaceutical Co., Ltd., Tsukuba, Japan.
Kamato
T
T
Fujihara
A
A
Takeda
M
M
D000403:Airway Resistance / Q000187:drug effects; D000758:Anesthesia; D000818:Animals; D001980:Bronchi / Q000187:drug effects*; D002927:Cimetidine / Q000494:pharmacology; D004285:Dogs; D004562:Electrocardiography; D015738:Famotidine / Q000494:pharmacology*; D005260:Female; D006221:Halothane; D006321:Heart / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006632:Histamine / Q000494:pharmacology; D008297:Male; D009609:Nitrous Oxide; D010424:Pentobarbital; D011433:Propranolol / Q000494:pharmacology
D015738:Famotidine; D002927:Cimetidine; D006632:Histamine; D011433:Propranolol; D010424:Pentobarbital; D009609:Nitrous Oxide; D006221:Halothane