Intravenous infusion of calcium antagonist, nicardipine, does not increase intracranial pressure: evaluation in a rat model of transient cerebral ischemia and reperfusion.
OBJECTIVE
Early use of parenteral antihypertensive drugs is recommended in acute ischemic stroke patients suffering hypertensive emergencies. Calcium antagonist has been widely employed, although there is controversy as to whether calcium antagonist can be administered safely to patients with intracranial hypertension. In a rat model of transient cerebral ischemia and reperfusion, we evaluated the effect of the calcium antagonist, nicardipine, on intracranial pressure (ICP). Using spontaneously hypertensive rats (SHRs), focal cerebral ischemia was induced by an intraluminal thread method. ICP was monitored continuously employing an intraparenchymal catheter. The mean arterial blood pressure (MABP) was reduced by infusing nicardipine intravenously.


RESULTS
Following 6 hours of transient ischemia and reperfusion, MABP was decreased by about 10 or 20% as compared to the baseline MABP with low-dose or high-dose nicardipine administration, respectively. ICP was significantly increased following reperfusion, although it did not increase further with nicardipine infusion.


CONCLUSIONS
Under conditions where ICP was high following reperfusion, nicardipine reduced blood pressure safely without increasing ICP in rats.
Matsuzaki
Toshinori
T
Department of Neurological Surgery, Nihon University School of Medicine, Tokyo 173-8610, Japan.
Kano
Tsuneo
T
Katayama
Yoichi
Y
Nakamura
Shin
S
Harada
Tadashi
T
D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D020520:Brain Infarction / Q000209:etiology / Q000517:prevention & control; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D007427:Intracranial Pressure / Q000187:drug effects*; D002546:Ischemic Attack, Transient / Q000188:drug therapy* / Q000503:physiopathology*; D008297:Male; D009529:Nicardipine / Q000627:therapeutic use*; D051381:Rats; D011918:Rats, Inbred SHR; D015424:Reperfusion
D002121:Calcium Channel Blockers; D009529:Nicardipine