1999 Fiscal Year Final Research Report Summary
EFFECTS OF NMDA-ATAGONISTS AND ALPHA2-ADRENERGIC AGONISTS ON SPINAL AND CEREBRAL MICROCIRCULATION -ASSESSED WITH CLOSED SPINAL AND CRANIAL WINDOW TECHNIQUE-.
Project/Area Number |
09671555
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Anesthesiology/Resuscitation studies
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Research Institution | GIFU UNIVERSITY |
Principal Investigator |
IIDA Hiroki DEPARTMENT OF ANESTHESIOLOGY AND CRITICAL CARE MEDICINE, ASSOCIATE PROFESSOR, 医学部, 助教授 (30159561)
|
Co-Investigator(Kenkyū-buntansha) |
DOHI Shuji DEPARTMENT OF ANESTHESIOLOGY AND CRITICAL CARE MEDICINE, PROFESSOR, 医学部, 教授 (40155627)
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Project Period (FY) |
1997 – 1999
|
Keywords | NMDA antagonist / Alpha2-adrenergic agonist / Cerebral vessel / Spinal vessel / Microcirculation |
Research Abstract |
Pentobaribital anesthetized animals were prepared for measurement of cerebral and spinal pial vessel diameter in a cranial and a spinal window preparation. We investigated the experiments according to following protocols. (1) To investigate the effect of systemic pretreatment with dexmedetomidine on cerebrovascular response to isoflurane and sevoflurane.; The vasodilation of cerebral pial vessels induced by isoflurane and sevoflurane could be attenuated by the systemic administration of dexmedetomidine, and this interaction between dexmedetomidine and volatile anesthetics showed no evidence of dose dependency. (2) To investigate the effect of ketamine on cerebrovascular response to isoflurane and sevoflurane.; Ketamine itself did not induce cerebrovascular dilation. The vasodilation of cerebral pial vessels induced by isoflurane and sevoflurane could be attenuated by the systemic administration of ketamine, and the response of pial vessels to PaCO2 also attenuated. (3) To investigate the effects of alpha1- and alpha2-adrenergic agonists on spinal and cerebral pial vessels: Dexmedetomidine and clonidine constricted spinal vessels in a concentration-dependent manner, but such vasoconstrictions were smaller than those induced by phenylephrine and epinephrine. In cerebral vessels, greater constriction was induced by dexmedetomidine and clonidine than those induced by phenylephrine and epinephrine. (4) To investigate the effects of spinal alpha2-adrenergic agonists on cerebrovascular reactivity to hypercapnia and hypoxia.: The presence of alpha2-adrenergic agonist administered intrathecally into the lumbar spinal region attenuated hypercapnic, but not hypoxic cerebral vasodilation, probably via a stimulation of central alpha2-adrenergic receptors of the central nervous system.
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Research Products
(12 results)