[Influence of long-term antihypertensive treatment on cerebral ischemia induced by bilateral common carotid artery ligation in SHRSR--protective effect of nicardipine hydrochloride].
We have already reported that the long-term antihypertensive treatment reduced the degree of cerebral ischemia induced by bilateral common carotid artery ligation (BLCL) in stoke-resistant spontaneously hypertensive rats (SHRSR). This antihypertensive treatment was achieved by the combination of captopril and hydroflumethiazide. In this study, nicardipine hydrochloride which is one of the Ca2+ antagonist was similarly administrated to SHRSR for 8-10 weeks (T-SHR). The effect of long-term antihypertensive treatment by this agent on cerebral ischemia induce by BLCL was investigated and compared with untreated SHRSR (U-SHR). The degree of cerebral ischemia 4 hr after BLCL was estimated by the levels of brain energy metabolites (ATP, lactate, c-AMP) and brain water content. The brain metabolites and water content were measured in the forebrain and hindbrain of each hemisphere. And also the histopathological study on brain vessels 3 hr after BLCL was achieved by using scanning electron microscopy (SEM). The blood pressure of T-SHR gradually declined from 185 +/- 10 mmHg (mean +/- S.D.) to 154 +/- 8 mmHg after 8-10 weeks of antihypertensive treatment. However the blood pressure of U-SHR spontaneously changed from 185 +/- 8 mmHg to 206 +/- 12 mmHg after 8-10 weeks. The blood pressure of T-SHR after the treatment was significantly lower than that of U-SHR. The levels of ATP and c-AMP in T-SHR after BLCL were statistically higher than those in U-SHR, and the lactate levels in T-SHR were significantly lower than in U-SHR in the both fore- and hindbrain.(ABSTRACT TRUNCATED AT 250 WORDS)
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000378:metabolism; D002545:Brain Ischemia / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D002339:Carotid Arteries / Q000601:surgery; D002536:Cerebral Arteries / Q000648:ultrastructure; D006973:Hypertension / Q000150:complications / Q000188:drug therapy*; D008026:Ligation; D008297:Male; D009529:Nicardipine / Q000008:administration & dosage / Q000627:therapeutic use*; D051381:Rats; D011918:Rats, Inbred SHR
D009529:Nicardipine