尼莫地平对脑出血患者局部脑血液、脑水肿及不同时间用药临床变化的影响

目的：动态观察尼莫地平对高血压脑出血患者局部脑血液（rCBF)、脑水肿和不同时间用药临床变化的影响。方法：随机将108例高血压脑出血患者分对照组和治疗组,并将治疗组再分为发病前12小时以内用药组和12小时以后用药组,行单光子发射断层扫描（SPECT）、临床疗效和动态观察;并随机从对照组和治疗组中分别抽出10例患者行SPCET、CT的动态观察,结果：治疗组rCBF、水肿带和临床疗效的改善显著优于对照组;12小时以内用药的临床疗效明显优于12小时以后用药。结论：早期使用尼莫地平对改善高血压脑出血后rCBF下降,提高临床疗效和减轻血肿周围水肿可能均有积极作用。     

Effects of topical methylene blue on cyclic GMP level,blood flow,and O2 consumption in focal cerebral ischaemia

Abstract

We hypothesized that a decrease in cyclic CMPa second messenger in the glutamate—nitric oxide pathway, would reduce oxygen consumption and improve O₂ balance in the ischaemic cerebral cortex. To test this hypothesis, a study was performed in unilateral middle cerebral artery occluded rats which were assigned to either a control or methylene blue (10^–3 m) group. Regional cerebral blood flow was determined using 14C-iodoantipyrine and regional arterial and venous O₂ saturations were determined by microspectrophotometry (n = 6). Cyclic GMP level was measured by radioimmunoassay (n = 8). Cuanylate cyclase and cyclic CMP-phosphodiesterase activities were determined in an additional set of control rats (n = 10). The cyclic CMP levels were not different between the ischaemic and contralateral areas in the control group. Compared to the cyclic CMP in the control ischaemic cortextopical methylene blue significantly decreased the cyclic CMP level by 56% in the ischaemic cortex of the methylene blue group. Ischaemia did not alter the activities of guanylate cyclase but mildly decreased cyclic GMP-phosphodiesterase. The regional cerebral blood flow and O₂ consumption in the control group were 50% and 32% lower than those in corresponding contralateral cortex. Topical methylene blue did not alter regional cerebral blood flow and O₂ consumption in the ischaemic cortex. Our data showed that cyclic CMP is not a major controller on O₂ supply or O₂ consumption in the ischaemic brain. [Neurol Res 1994; 16: 449-455]     

Colloidal volume expansion during acute cerebral ischaemia: assessed by local cerebral blood flow and computerized power ratio index

Colloidal volume expansion during acute cerebral ischaemia was assessed by local cerebral blood flow (CBF) and the power ratio index (PRI) in 8 anaesthetized Macaque monkeys. Focal cerebral ischaemia was produced by right middle cerebral artery occlusion. The animals were then volume expanded (to maximum cardiac output) with 6% hetastarch and then exsanguinated to baseline cardiac output. During volume expansion, local CBF in the ischaemic hemisphere increased from 25 ± 12 to 39 ± 23 cc/100 g/min (p > 0.01) and during exsanguination decreased to 32 ± 18 cc/100 g/min. Local CBF did not change significantly in the nonischaemic hemisphere. EEG power data, as assessed by PRI [(delta + theta power/alpha + beta power) × 100] changed significantly during blood volume manipulation. The mean PRI value in the right hemisphere deteriorated by increasing from 65 ± 22 to 94 ± 25 (p > 0.01) following vessel occlusion but improved by decreasing to 81 ± 23 (p > 0.05) following volume expansion. Following exsanguination, the PRI value increased to 87 ± 21. These data demonstrate the benefits of volume expansion during acute cerebral ischaemia. Changes in local CBF were consistently associated with changes in the PRI maps and values.     

The relationship between glutamate release and cerebral blood flow after focal cerebral ischaemia in the cat: effect of pretreatment with enadoline (a kappa receptor agonist)

The effect of the κ-opioid agonist enadoline (CI-977) upon the relationship between cerebral blood flow and glutamate release was simultaneously assessed (using microdialysis and hydrogen clearance techniques respectively) at the same anatomical locus in the cerebral cortex (suprasylvian gyrus) after permanent middle cerebral artery (MCA) occlusion in halothane-anaesthetised cats. During controlled graded ischaemia, pretreatment with enadoline (0.3 mg/kg i.v. followed by continuous infusion at 0.15 mg/kg/h), initiated 30 min prior to MCA occlusion, significantly attenuated the marked increases in extracellular glutamate, aspartate and GABA observed in the focal ischaemic penumbra. The present data are consistent with the hypothesis that the neuroprotective efficacy of enadoline in focal cerebral ischaemia is due to inhibition of glutamate release in the ischaemic penumbra.     

尼莫地平灌洗对自发性蛛网膜下腔出血脑血流的影响

目的 已证实尼莫地平液灌洗可缓解蛛网膜下腔出血(SAH)后脑血流速度的异常增高,现拟研究其对SAH所致异常脑血流灌注的影响.方法 14头雄性小型实验猪随机分为假手术组、SAH组和灌洗组.开颅向鞍上池注入5 ml自体股动脉血制备SAH模型,4 d后用40 ml尼莫地平稀释液(0.04 mg/ml)灌洗灌洗组蛛网膜下腔.30 min后行CT/SPECT扫描,图像经重建断层、对齐及空间标准化后于CT模板绘制感兴趣区再与对应层面SPECT图像配准计算大脑小脑比(CCR)和相对离散度(RD)以半定量描述右侧大脑半球血流量和血流分布异质性.结果 假手术组、SAH组和灌洗组CCR分别为1.988±0.346、1.382±0.192和1.503±0.107;RD分别为0.389±0.015,0.417±0.015和0.425±0.018.SAH组CCR和RD与假手术组差异有统计学意义(P<0.05);灌洗组CCR和RD均与SAH组差异无统计学意义(P>0.05),提示尼莫地平灌洗对SAH所致的半球血流量下降及脑血流分布异质性增加无显著缓解作用.结论 尼莫地平灌洗不能缓解SAH后异常脑血流灌注的机制尚不明确,可能与难以缓解SAH引起的脑微循环障碍有关.     

Effect of nimodipine on the autoregulation of cerebral blood flow studied by laser-Doppler flowmetry

The present work examines whether nimodipine impairs autoregulation of CBF during hypotension. The CBF of 16 anesthetized rabbits was measured with a laser-Doppler flowmetry probe placed on the external surface of a plexiglas window, chronically inserted in the skull. Autoregulation was triggered by aortic bleeding. First, the effects of three doses of nimodipine (1, 3 and 10 μg/kg) and the solvent were studied in 10 rabbits in which MABP was maintained at 50 mmHg for one minute. Second, 10 μg/kg i.v. nimodipine was administered to 6 rabbits in which MABP was kept at 30 mmHg for one minute. Before bleeding, the 10 μg/kg dose significantly decreased MABP (from 96 ± 11mmHg to 81 ± 11mmHg, P < 0.01) and increased CBF (from 104 ± 20%to147 ± 25%, P < 0.01) as compared to the solvent. In the first set of experiments, only the 10 μg/kg dose suppressed the autoregulatory vasodilation, but CBF was not different from control (84 ± 17%versus87 ± 12%), probably because of the previous induced vasodilation. In the second set of experiments, active vasodilation occurred and the CBF during hypotension was not different from control (72 ± 26%versus65 ± 11%). We conclude that under nimodipine the triggering of the active autoregulatory vasodilation is dependent on both the severity of hypotension and the previous nimodipine-induced vasodilation.     

尼莫地平注射液对脑出血急性期患者高血压调控的体会

目的观察尼莫地平注射液对脑出血急性期患者高血压调控的作用。方法收集本院2012年2月-2012年5月的脑出血住院患者14例,住院治疗期间均应用尼莫地平注射液静脉泵点,比较治疗前后平均动脉压及病情。结果病情危重行锥颅引流术1例(7%),病情明显好转的13例(93%)。治疗后平均动脉压均明显降低。结论尼莫地平注射液可用于脑出血患者高血压急性期的调控。     

大鼠蛛网膜下腔出血后脑局部血流量与血脑屏障动态变化

目的：探讨大鼠蛛网膜下腔出血（SAH）后局部脑血流（rCBF）与血脑屏障（BBB）超微结构的动态变化规律和尼莫地平（Nim）的作用特点。方法：通过大鼠枕大池自体血注入法制备SAH后脑血管痉挛（CVS）模型，在SAH后1h、4h、12、24h、3d、7d、14d、及21d等不同时相点，利用激光普勒技术和电镜对各组大鼠局部脑血流与血脑屏障超微结构变化进行观察。结果：SAH后大鼠的rCBF明显下降且具有“两期”反应，在SAH后1h后rCBF有所恢复，4h后再度降低，并可持续至21d。BBB损害改变在SAH后早期即可观察到。Nim对rCBF降低和BBB损害均有改善作用。结论：SAH后rCBF与BBB超微结构的动态变化符合CVS的发展规律，可以反映该时期CVS的状态。早期应用Nim可以改善SAH后CVS，并对BBB的损害有一定保护作用。     

Influence of blood viscosity to cerebral blood flow in older humans compared to young subjects

Objective

Since blood viscosity (BV) is one of the most important factors determining blood flow, this study aimed to investigate the possible correlation between increased blood viscosity and reduction of regional cerebral blood flow (rCBF) in healthy ageing.

Methods

Male subjects were distributed in two groups: “young”, aged 20-30 (27 volunteers), or “elderly”, aged 60-70 (50 volunteers). Whole blood viscosity was obtained with a Wells-Brookfield Cone/Plate Viscometer. Cerebral blood flow was analysed by means of single photon emission computed tomography (SPECT).

Results

The mean BV values were 3.28 ± 0.43 mPa in the group of young volunteers and 4.33 ± 0.73 mPa in the group of elderly volunteers (t = −6.9, p < 0.0001). The elderly had a lower blood flow than the young in the following regions: bilateral parietal; temporal-parietal and temporal of the left hemisphere. Pearson’s correlation between BV and rCBF showed a good inverse correlation when the BV was above 3.95 ± 0.83 mPa.

Conclusions

Our results point to a close relationship between the two parameters analysed, BV and rCBF. The impairment in rCBF observed in the elderly volunteers might be due to an increase in BV, among other factors.

Significance

These findings suggest interesting possibilities for the treatment/prevention of brain ageing.     

Endorphinergic mechanisms in cerebral blood flow autoregulation

The influence of naturally occurring opioid peptides (Met-enkephalin (Met-Enk), dynorphin (DYN), β-endorphin (β-EP)) as well as morphine and the opiate antagonist naloxone and specific antisera on cerebral blood flow autoregulation was studied in anesthetized, artificially ventillated rats. Local hypothalamic blood flow (CBF, H₂-gas clearance technique) and total cerebral blood volume (CBV, photoelectric method) were simultaneously recorded. Autoregulation was tested by determining CBF and CBV during consecutive stepwise lowering of the systemic mean arterial pressure to 80, 60 and 40 mm Hg, by hemorrhage. Resting CBF decreased following Met-Enk, DYN, β-EP or morphine administration without simultaneous changes in CBV. Naloxone administration, on the contrary, increased CBV without affecting local CBF. Autoregulation of cerebral blood flow was maintained until 80 mm Hg, but not completely at 60 and 40 mm Hg arterial pressure in the control group. General opiate receptor blockade by 1 mg/kg s.c. naloxone abolished autoregulation at all levels, since CBF and CBV passively followed the arterial pressure changes. Intracerebroventricularly injected naloxone (1 μg/kg) as well as a specific antiserum against β-EP, but not against Met-Enk or DYN, resulted in the very same effect as peripherally injected naloxone. The present findings suggest that central, periventricular β-endorphinergic mechanisms might play a major role in CBF autoregulation.     

尼莫地平治疗脑出血后缺血性脑损害的疗效观察

目的研究尼莫地平治疗脑出血后缺血性脑损害的疗效,进一步探讨尼莫地平的作用机制。方法应用尼莫地平治疗脑出血后缺血性脑损害36例,与对照组30例常规治疗进行比较。结果尼莫地平治疗组有效率94.4%,对照组46.7%（P〈0.05）,尼莫地平治疗组神经功能缺损评分显著减少,与对照组相比差异显著（P〈0.01）。结论提示尼莫地平早期使用对减少和治疗脑出血后缺血性脑梗死均又明显的疗效。     

静滴尼莫地平治疗脑出血的疗效研究

目的 :观察尼莫地平治疗急性脑出血的临床疗效。方法 :应用前瞻性随机单盲方法 ,对 96例经CT证实为急性脑出血病人 ,在起病 4 8h内随机分为治疗组和对照组 ,治疗前后比较两组病人神经功能缺损程度积分差及颅内血肿体积 ,血肿周围水肿带面积的改变。结果 :尼莫地平治疗组较对照组血肿周围水肿带面积明显缩小 (P <0 0 5 ) ,神经功能缺损评分明显改善 (P <0 0 1) ,血肿体积则改变不明显。结论 :在脑出血急性期应用尼莫地平治疗 ,可明显改善其病情     

Caffeine-induced cerebral blood flow changes in schizophrenia

Summary Cerebral blood flow (CBF) measurements and mental status examinations were performed before and 30 min after oral administration of 250 mg of caffeine or a placebo given under double-blind conditions, in two groups of patients with schizophrenia. Caffeine produced significant CBF reductions but no changes in the patient's clinical condition.     

尼麦角林对偏头痛患者脑血流的影响

目的研究尼麦角林对成人偏头痛患者脑血流动力学的影响。方法156例偏头痛患者随机分为试验组（76例）和对照组（80例）,同时选择60例健康体检者作为健康对照组,试验组应用尼麦角林治疗,而对照组应用布洛芬治疗,应用经颅多普勒超声（TCD）技术检测试验组和对照组治疗前后及健康对照组双侧大脑中动脉、大脑前动脉、大脑后动脉的收缩期峰值血流变化。结果（1）156例偏头痛患者服药前头痛侧与非头痛侧比较,大脑中动脉、大脑前动脉、大脑后动脉的收缩期峰值血流速度（Vs）有显著差异;两组头痛侧之间及非头痛侧之间无显著性差异。治疗后比较,对照组差异明显,试验组无明显差异;两组头痛侧比较有显著性差异;（2）156倒患者服药前头痛侧大脑中动脉、大脑前动脉、大脑后动脉的收缩期峰值血流速度与健康对照组比较增快。治疗后：对照组变化不明显;试验组头痛侧大脑中动脉、大脑前动脉、大脑后动脉的收缩期峰值血流速度降低,且与健康对照组差异不明显。结论尼麦角林可明显改善偏头痛患者的脑血流,防止偏头痛的发作。     

黄芪对大鼠脑缺血血脑屏障及脑血流的影响

利用大鼠局灶性脑缺血再灌流和全脑缺血再灌流损伤两种动物模型，观察黄芪注射液对脑缺血后再灌注期间血脑屏蔽及脑血流的保护作用。结果显示，与相庆对照组比较，不论是全脑缺血还是局灶性脑缺血１ｈ后再灌流３ｄ，应用黄芪的各组动物脑水肿明显减轻，血脑屏障通透性改善，大脑局部血流量显著增加。     

尼莫地平防治脑梗死后癫痫疗效探讨

目的 :探讨脑梗死后癫痫防治办法。方法 :随机分组 ,对比观察组和对照组脑梗死后癫痫发生率。结果 :观察组癫痫发生率明显低于对照组 (P <0 0 5 )。结论 :尼莫地平可有效防治脑梗死后癫痫、降低癫痫发生率。     

Xenon CT measurement of cerebral blood flow in hydrocephalus

Since the recognition of normal-pressure hydrocephalus as an entity (1965), ventriculo-atrial or peritoneal shunting has been proposed as a treatment for this disease. Unfortunately, selection of patients who would benefit from shunting has always been difficult, and no clinical or brain imaging criteria have been entirely satisfactory. Functional studies intended to measure the local cerebral blood flow (ICBF) seem more promising. Xenon CT CBF measurement has been chosen because of its ability to measure deep white matter ICBF with good spatial resolution. This preliminary study reports the results of ICBF measurement in four patients examined by this technique before and after shunting or cerebrospinal fluid subtraction by lumbar puncture. In this small collective the two patients who improved clinically after shunting or lumbar puncture also had a substantial improvement in deep white matter ICBF.Presented at the Consensus Conference: Hydrocephalus '92, Assisi, Italy, 26–30 April 1992     

血液光量子疗法对局灶性脑缺血大鼠大脑皮层局部血流量和脑水肿的影响

本文动态观测了光量子疗法治疗血栓栓塞性脑缺血大鼠,大脑皮层局部血流量(rCBF)及脑水肿的变化。结果:缺血6小时经光量子血液治疗2小时后,rCBF于注后30min明显增加,达19.78％(P<0.01),以后各点维持在一定水平,2小时增加到19.30(P<0.05)。脑组织比重:缺血中心区未见明显改善(P>0.1)而半暗区组织比重非常明显增加(P<0.001),可见水肿明显减轻。说明光量子疗法增加rCBF,减轻半暗区水肿。     

脑出血大鼠局部脑血流量的改变及尼莫地平的干预作用

目的 探讨脑出血(ICH)后脑组织局部脑血流量(rCBF)的改变及尼莫地平的干预作用.方法 SD大鼠72只随机分成ICH组、尼莫地平组和正常对照组,采用Nath 改良法建立ICH模型,尼莫地平组大鼠腹腔注射尼莫地平1 mg/kg,对照组注射等量生理盐水,在大鼠ICH后1 h、4 h、24 h、48 h用氢清除法测定其rCBF并与正常大鼠比较.结果 ICH组出血后1 h、48 h组出血侧皮质、基底节区rCBF较正常对照组明显下降(均P<0.05); 不同时间点尼莫地平组出血侧皮质、基底节区rCBF显著高于ICH组(均P<0.05).ICH组出血后4 h、24 h rCBF有回升,与正常对照组差异无统计学意义.尼莫地平组出血后各时间点出血侧皮质、基底节区rCBF与正常对照组差异无统计学意义.结论 ICH后有明显rCBF降低,尼莫地平能干预此改变.     

易卒中型肾血管性高血压大鼠的脑血流自动调节下限与最低耐受压

目的　研究易卒中型肾血管性高血压大鼠 (RHRSP)的脑血流 (CBF)自动调节下限及其最低耐受压。　　方法　用氢清除法测定RHRSP和正常SD大鼠在不同低血压水平时 ,一侧顶枕交界区皮质和海马的局部CBF(rCBF) ;72小时后计算RHRSP和SD大鼠海马CA1 区神经细胞 (CA1 NC)线粒体的体密度 (Vv)、比表面 (δ)、平均体积 ( V)和数密度 (Nv) ,　　 结果　正常SD大鼠在平均动脉压 (MABP)为 1 0 67kPa、9 3 3kPa和 8kPa时 ,rCBF值无显著减少。在MABP为 1 0 67kPa时 ,RHRSP的rCBF值显著减少 ;超微结构观察发现CA1 NC无明显缺血改变 ,当MABP为 9 3 3kPa时 ,CA1 NC缺血明显 ;细胞形态分析发现 9 3 3kPa组与 1 0 67kPa组比较 ,前者线粒体的Vv和 V显著增大 ,δ和Nv显著减小。　　结论　RHRSP的CBF自动调节下限上移至 1 0 67kPa,并与其最低耐受压十分接近 ,表明RHRSP是一种研究高血压脑血管损害较理想的动物模型