Effects of the calcium antagonist NB-818 on cerebral blood flow.
The effects of intravenous injection of NB-818, isopropyl methyl 2-carbamoyloxymethyl-6-methyl-4-(2,3-dichlorophenyl)-1,4-dihydropyridine-3,5- dicarboxylate, on regional cerebral blood flow were studied in rabbits and Rhesus monkeys, using the hydrogen clearance technique. The above effects were compared with those of nicardipine and nimodipine. In rabbits, NB-818 (10 micrograms/kg i.v.) increased both cerebral cortical blood flow (rCBF) and cerebellar cortical blood flow by about 80% of the predrug level with a moderate decrease in mean arterial blood pressure, and no increase in skeletal muscle blood flow. The increase in cerebral blood flow with NB-818 was as great as that with nicardipine or nimodipine. In Rhesus monkeys, NB-818 (10-20 micrograms/kg i.v.) increased rCBF by about 30% of the predrug level, and its effect continued 30-60 min after dosing. The increase in rCBF with NB-818 was greater than that with nicardipine. The results from the present study indicate that NB-818 predominantly increases rCBF with a concomitant moderate hypotension, and its action is greater than that of nicardipine or nimodipine.
Nishikibe
M
M
Central Research Laboratories, Banyu Pharmaceutical Co., Ltd., Tokyo, Japan.
Nakajima
A
A
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004095:Dihydropyridines / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D008253:Macaca mulatta; D008297:Male; D009529:Nicardipine / Q000494:pharmacology; D009553:Nimodipine / Q000494:pharmacology; D011817:Rabbits; D012016:Reference Values; D013045:Species Specificity
D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D009553:Nimodipine; C048962:NPK 1886; D009529:Nicardipine