CEREBRAL CIRCULATORY RESPONSE TO HYPERCAPNIA - EFFECTS OF LESIONS OF CENTRAL DOPAMINERGIC AND SEROTONINERGIC NEURON SYSTEMS
CEREBRAL CIRCULATORY RESPONSE TO HYPERCAPNIA - EFFECTS OF LESIONS OF CENTRAL DOPAMINERGIC AND SEROTONINERGIC NEURON SYSTEMS
复制标题
DOI：
10.1016/0006-8993(81)90403-0
复制
发表时间：
1981-01-01
期刊：
影响因子：
2.9
通讯作者：
STENEVI, U
中科院分区：
文献类型：
--
作者：
DAHLGREN, N;LINDVALL, O;STENEVI, U
研究了在正常碳酸和高碳酸条件下，中枢多巴胺能和多巴胺能神经元系统影响脑血流量的可能性。用放射自显影技术，以[14 C]碘安替比林作为扩散示踪剂，测定黑质纹状体多巴胺通路单侧6-羟基多巴胺损伤对局部CBF（1-CBF）的影响。在正常碳酸血症或高碳酸血症条件下，病变对CBF无重大影响。对高碳酸血症的循环反应轻微增强（约10%）。在高碳酸血症条件下，尾壳核血流量的显著增加通常可通过由黑质纹状体系统释放多巴胺引起的轻微血管收缩来调节。采用改良的Kety-Schmidt惰性气体技术评价脑室内5，7-二羟色胺对脑氧代谢率（CMRO 2）和CBF的影响。切除了. apprx. 90%的皮质5-羟色胺对高碳酸血症的循环反应没有影响，也没有改变CMRO 2。然而，在碳酸正常的条件下，病变似乎诱导CMRO 2的轻微增加，表明肾上腺素能系统对大脑中的代谢率施加了一种抑制性静息张力。
The possibility that the central dopaminergic and serotoninergic neuron systems inluence CBF [cerebral blood flow] under normocapnic and hypercapnic conditions was studied. The effect of unilateral 6-hydroxydopamine lesion of the nigrostriatal dopamine pathway on local CBF (1-CBF) was measured autoradiographically with [14C]iodoantipyrine as the diffusible tracer. The lesion caused no major effect on CBF under normocapnic or hypercapnic conditions. The circulatory response to hypercapnia was slightly enhanced (.apprx. 10%) in the denervated caudate-putamen. Under hypercapnic conditions the pronounced increase in blood flow in the caudate-putamen may normally be modulated by a slight vasoconstriction caused by dopamine release from the nigrostriatal system. The effect of intraventricular 5,7-dihydroxytryptamine on cerebral metabolic rate for O2 (CMRO2) and CBF was evaluated using a 133Xe modification of the Kety-Schmidt inert gas technique. The lesion, which removed .apprx. 90% of cortical 5-hydroxytryptamine, had no effect on the circulatory response to hypercapnia, nor did it alter CMRO2. Under normocapnic conditions, though, the lesion seemed to induce a minor increase in CMRO2, indicating that the serotoninergic system exerts a depressant resting tone on metabolic rate in the brain.