The effects of prostaglandin E1 and nicardipine on cerebral blood flow, blood volume and oxygenation in young rabbits.
The effects of the vasodilators, prostaglandin E1 and nicardipine, on cerebral blood flow (CBF), cerebral blood volume and oxygenation were studied in young rabbits of 2 weeks of age using the hydrogen clearance method and near infrared spectrophotometry. Prostaglandin E1 decreased CBF in the cerebral cortex. However, cerebral oxygenation through oxyhemoglobin and cytochrome a, a3 was not affected by the drug. On the other hand, nicardipine increased CBF in the cerebral white matter and diencephalon in spite of the fall in blood pressure and the decreased cerebral blood volume due to deoxyhemoglobin. Oxidized cytochrome a, a3 variably increased. These results suggest that nicardipine, a calcium channel antagonist, may cause dilation of cerebral arterioles, increase CBF and cellular oxidation, and cause constriction of cerebral veins, in contrast to the little effect of prostaglandin E1 on cerebral vessels.
Koyama
K
K
Division of Pharmacy, National Institute of Nishi-Koufu Hospital, Yamanashi, Japan.
Mito
T
T
Takashima
S
S
Suzuki
S
S
D000527:Alprostadil / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001810:Blood Volume / Q000187:drug effects*; D002540:Cerebral Cortex / Q000098:blood supply; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004027:Diencephalon / Q000098:blood supply; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006454:Hemoglobins / Q000378:metabolism; D007262:Infusions, Intravenous; D009529:Nicardipine / Q000008:administration & dosage / Q000494:pharmacology*; D010100:Oxygen / Q000097:blood*; D010108:Oxyhemoglobins / Q000378:metabolism*; D011817:Rabbits; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects
D006454:Hemoglobins; D010108:Oxyhemoglobins; D009529:Nicardipine; D000527:Alprostadil; D010100:Oxygen