Neuronal control of Cerebrovascular Bed

脑血管床的神经元控制

基本信息

批准号：
06671420
负责人：
MAEDA Minoru
金额：
$ 1.41万
依托单位：
JUNTENDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1996
项目状态：
已结题

项目摘要

There are two possible causes for the development of plateau waves : persistent intracranial hypertension and cerebral vasomotor reaction. Previously we investigated the function of noradrenergic cell group (locus coeruleus complex, LC ; medullary reticular formation, MRF) and the cholinoceptive pontine area (CPA) in the generation of plateau waves. This study investigated the function of the cholinergic basal forebrain in control of ICP and cerebrovascular bed.Ten chloralose-anesthetized-immobilized cats with Kaolin-induced hydrocephalus and six normal rats were used of the experiments. BP,ICP and ETCO_2 were measured continuously. The CBF was measured by the hydrogen clearance method. The first experiments recorded single unit spikes continuously during ICP・variations using tungsten-microelectrode in the dorsomedial hypothalamic nucleus (DMH) of the cats. In the second series of experiments injection needles were inserted for microinjection of glutamate or Ach into the magnocellular … More basal nucleus (nucleus basalis of Meynert, NBM ; substantia innominata, SI) of the rats or the DMH of the cats.Glutamate or Ach microinjection into the NBM and SI caused consistent increases in ICP associated with slightly decreased BP,Ach microinjection into the DMH produced a persistent increase in ICP with a marked decrease in BP.ETCO_2 concentration changed little. Ach microinjection into the NBM or the DMH also induced consistent increases in CBF in the cerebral cortex. The DMH-neuron spike activities increased before onset and during spontaneous ICP elevation. The firing rate of the DMH-neuron discharge was increased in phase with the plateau wave like ICP-variations elicited by microinjection of Ach into the CPA or the contralateral DMH.However, some DMH-neurons demonstrated no suppression or promotion of spike activities during increased ICP.Plateau waves may result from an increase in CBV.Glutamate or Ach induced ICP changes in the present study have resulted from increased CBV in response to reduced cerebral vaso-constrictor tone. Our previous and present results suggest that activity within the cholinergic basal forebrain (NBM,SI,DMH), CPA,LC and MRF contributes to ICP changes and is the intrinsic neuronal origins controlling cerebrovascular bed. Less

平台波的产生可能有两个原因：持续性颅内高压和脑血管舒缩反应。之前我们研究了去甲肾上腺素能细胞群（蓝斑复合体，LC；髓质网状结构，MRF）和胆碱感受性桥脑区（CPA）的功能。本研究调查了胆碱能基底前脑在控制 ICP 和脑血管中的功能。实验采用10只氯醛糖麻醉的高岭土诱发脑积水的猫和6只正常大鼠，采用氢清除法连续测量CBF。在第二系列实验注射中，在猫的下丘脑背内侧核（DMH）中使用钨微电极连续进行ICP·变化。将针插入大鼠的大细胞基底核（Meynert 基底核，NBM；无名质，SI）或猫的 DMH 中显微注射谷氨酸或 Ach。将谷氨酸或 Ach 显微注射到 NBM 和 SI 中引起一致ICP 的增加与血压的轻微降低相关，Ach 显微注射到 DMH 中产生了 ICP 的持续增加，同时 BP 的显着降低BP.ETCO_2 浓度变化不大。Ach 微量注射到 NBM 或 DMH 中也引起大脑皮层 CBF 的持续增加。DMH 神经元尖峰活动在发作前和自发 ICP 升高期间增加。与平台波同相增加，如将 Ach 显微注射到 CPA 或对侧 DMH 中引起的 ICP 变化。然而，一些 DMH 神经元在增加期间没有表现出抑制或促进尖峰活动。 ICP.平台波可能是由CBV增加引起的。在本研究中，谷氨酸或乙酰胆碱引起的ICP变化是由于大脑血管收缩张力降低而导致的CBV增加所致。我们之前和目前的结果表明，胆碱能基底前脑内的活动。 (NBM、SI、DMH)、CPA、LC 和 MRF 导致 ICP 变化，是控制脑血管床的内在神经起源。