J Korean Neurosurg Soc.
1989 Jan;18(1):23-31.
Effect of Nicardipine on Pressor Response to Raised Intracranial Pressure and alpha-Adrenoceptor Agonist
- Affiliations
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- 1Department of Neurosurgery, Chonam University Medical School, Gwang-ju, Korea.
Abstract
- The effect of nicardipine was investigated on hypertension due to raised intracranial pressure, pressor response of alpha-adrenoceptor agonists in the dissected thoracic aorta. Intracerebroventricular(icv) and intravenous(iv) nicardipine produced dose-dependent depressor response and bradycardiac effect, especially marked response was observed following iv injection. The pressor response to raised intracranial pressures was potentiated following iv injection of 50 microgram/kg nicardipine but was markedly inhibited following iv 100 microgram/kg injection, and was not affected following icv 50 microgram/kg administration but was markedly inhibited following icv administration of 100-200 microgram/kg nicardipine. The nicardipine inhibited contractile effect of KCI 35 mM in a dose-dependent fashion but did not affect that of Ne and ME. These data suggest that nicardipine caused hypotensive effect by blocking calcium influx in the peripheral vessels and that direct effect of nicardipine on central nervous system involves the hypotensive action. Conclusively, the inhibitory effect of nicardipine on the pressor response to the intracranial pressure elevation may be induced by these two mechanisms.