Age-related differences in the depressor responses to sodium nitroprusside and nifedipine in anaesthetized rats.
1. The blood pressure lowering actions of sodium nitroprusside (SNP) and nifedipine were compared in 5-month and 22-month pentobarbitone-anaesthetized Sprague-Dawley rats. 2. Five-month-old rats had significantly higher resting diastolic blood pressure (DBP) than 22-month rats and this may explain why SNP (1-30 micrograms kg-1) produced significantly greater falls of DBP in absolute terms in 5-month animals. 3. The depressor responses to nifedipine were similar in young and old rats, despite differences in resting DBP, suggesting that, in comparison to nifedipine, SNP is less effective at lowering DBP in aged rats.
Docherty
J R
JR
Department of Clinical Pharmacology, Royal College of Surgeons in Ireland, Dublin.
D000375:Aging / Q000187:drug effects*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D005292:Ferricyanides / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009543:Nifedipine / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D005292:Ferricyanides; D009599:Nitroprusside; D009543:Nifedipine; D007545:Isoproterenol