Effects of four calcium channel blockers on central cardiovascular control.
The cardiovascular effects of intravenous and intracisternal administration of low doses of calcium channel blockers (nicardipine: 0.3 to 10 micrograms/kg; nifedipine: 0.01 to 10 micrograms/kg; verapamil: 0.003 to 0.1 mg/kg and diltiazem: 1 to 300 micrograms/kg) were investigated in pentobarbital-anesthetized dogs. All studied calcium channel blockers induced a decrease in blood pressure and an increase in heart rate after intravenous injection. In contrast, the same doses injected by intracisternal route elicited an increase in both blood pressure and heart rate. These results show that blockade of central calcium channels in dogs increases blood pressure and heart rate and suggest that the pharmacological effects of these drugs are the addition of peripheral and central actions. However, the magnitude of these central properties seems to be higher for dihydropyridine than for phenylalkylamine or benzothiazepine derivatives.
Montastruc
J L
JL
Laboratoire de Pharmacologie Médicale et Clinique, INSERM U-317, Faculté de Médecine, Toulouse, France.
Damase-Michel
C
C
Dang-Tran
L
L
Montastruc
P
P
D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004110:Diltiazem / Q000494:pharmacology; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D009529:Nicardipine / Q000494:pharmacology; D009543:Nifedipine / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
D002121:Calcium Channel Blockers; D014700:Verapamil; D009529:Nicardipine; D004110:Diltiazem; D009543:Nifedipine