Effects of the calcium antagonist nilvadipine on focal cerebral ischemia in spontaneously hypertensive rats.
We studied the efficacy of preischemic and postischemic systemic treatment with a new calcium antagonist nilvadipine in a permanent focal cerebral ischemia model of spontaneously hypertensive rats. Rats that underwent microsurgical middle cerebral artery occlusion were blindly assigned to a single intraperitoneal injection of nilvadipine (0.32 mg/kg) or the same amount of polyethylene glycol either 15 minutes before, immediately after, 1 hour after, or 3 hours after occlusion of the left middle cerebral artery. Neurologic conditions of rats were closely examined, and rats were killed 24 hours later. Removed brains were sliced coronally, stained with triphenyltetrazolium chloride, and the size of infarct was determined. Although no neurologic improvements were observed in the treated rats, the area of infarcts was significantly reduced in the groups treated before, immediately after, and 1 hour after occlusion of the middle cerebral artery. Treatment started 3 hours after occlusion was ineffective.
Shiino
A
A
Department of Neurosurgery, Shiga University of Medical Science, Ohtsu, Japan.
Matsuda
M
M
Susumu
T
T
Handa
J
J
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002545:Brain Ischemia / Q000188:drug therapy* / Q000503:physiopathology; D002121:Calcium Channel Blockers / Q000494:pharmacology / Q000627:therapeutic use*; D002536:Cerebral Arteries / Q000187:drug effects; D002544:Cerebral Infarction / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D002560:Cerebrovascular Circulation / Q000187:drug effects; D008297:Male; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D011918:Rats, Inbred SHR
D002121:Calcium Channel Blockers; C035100:nilvadipine; D009543:Nifedipine