硝苯地平治疗前后高血压患者血浆神经肽及儿茶酚胺的变化

观察硝苯地平治疗前及治疗２个月后高血压患者血压、血浆β－内啡肽（β－ＥＰ）、亮啡肽（ＬＥＫ）、精氨酸加压素（ＡＶＰ）、Ｐ物质（ＳＰ）、神经降压肽（ＮＴ）、去甲肾上腺素（ＮＥ）及肾上腺素（Ｅ）的变化,发现治疗前ＳＰ、ＮＴ、β－ＥＰ和ＬＥＫ与对照组比较明显降低（Ｐ〈０．０１）,ＡＶＰ、ＮＥ、Ｅ明显增高（Ｐ〈０．０１）．治疗后与治疗前比较ＳＰ、ＮＴ、β－ＥＰ、ＬＥＫ、ＮＥ、Ｅ明显增高（Ｐ〈０．０１）,Ａ     

神经肽Y对松果腺的作用

神经肽Ｙ对松果腺的作用自从１９８２年Ｔａｔｅｍｏｔｏ等分离出神经肽Ｙ（ＮｅｕｒｏｐｅｐｔｉｄｅＹ，ＮＰＹ）以后，许多研究已经表明，ＮＰＹ广泛地分布于中枢和外周神经系统，且常在交感神经系统中与去甲肾上腺素共存。ＮＰＹ的基因由７．２ｋｂ组成，经ＣＤＮＡ序...     

高血压血浆神经肽Y含量的变化及意义

神经肽Ｙ(ＮＰＹ)是具有广泛生物活性的多肽 ,广泛分布于机体组织中 ,对多种生理活动起重要的调节作用 ,并参与机体应激反应及高血压的病理生理过程。本研究通过对高血压患者血浆ＮＰＹ的含量测定 ,探讨ＮＰＹ引起血压升高的病理生理机制。对象与方法一、对象 :(1)高血压组 :80例 ,男 5 4例 ,女 2 6例 ,年龄 36～ 84岁 ,平均 5 8 3± 9 8岁 ;符合ＷＨＯ/ＩＳＨ 1999年的定义和分级标准 ,并根据心血管病危险的绝对水平进行分层 ;平均收缩压 179 5±2 5 6ｍｍＨｇ ,平均舒张压 10 2 4± 9 7ｍｍＨｇ。 (2 )正常对照组 :4 0例 ,男 2 5例 ,女 …     

大鼠焦虑模型血浆神经肽Y的变化

目的 探讨大鼠的焦虑状态血浆神经肽Y的变化.方法 ①将16只SD大鼠按体重随机分为两组:对照组和模型组.采用空瓶刺激法制造焦虑模型.②放射免疫分析法(RIA)检测大鼠血浆神经肽Y浓度.③统计分析分别采用单因素方差分析和独立t检验.结果 ①空瓶应激行为学结果发现,造模组的攻击行为和修饰行为得分均高于对照组,差异有显著性意义(P＜0.05).②模型组大鼠血浆NPY浓度明显高于对照组(P＜0.05).结论 焦虑状态下大鼠血浆神经肽Y水平增高.     

急性脑卒中急性期血浆神经肽Y含量与临床意义

神经钛(NPY)是一种含36个氨基酸基的多肽,广泛分布于多种动物及人体的许多组织中,在脑的各个区域都存在[1],主要与去甲肾上腺素(NE)共存于交感神经末梢并与NE一起释放[2],有人认为它是交感神经的辅递质,具有强烈的收缩血管作用,可诱发血压升高[3],并参与脑血栓形成[4].本文旨在探讨急性脑卒中急性期血浆NPY与脑损害程度以及血压关系.     

氨氯地平对不稳定型心绞痛患者血浆神经肽Y、内皮素水平的影响

目的：探讨氨氯地平对不稳定型心绞痛患者血浆神经肽Y（NPY）、内皮素（ET）水平的影响及意义。方法：应用放射免疫法同步测定不稳定型心绞痛组和正常对照组的血浆NPY、ET的浓度水平,在氨氯地平治疗15d后再复测进行比较。结果：不稳定型心绞痛组患者血浆NPY、ET均明显高于正常对照组,在治疗前血浆NPY/ET比值明显升高,且NPY与ET呈显著正相关,但在治疗后15d不稳定心绞痛组患者血NPY、ET水平又下降至正常水平。结论：氨氯地平能有效地降低不稳定型心绞痛者的血浆NPY、ET的水平,故而能解除冠脉痉挛状态。     

单纯性肥胖儿童血浆神经肽Y的变化

目的:探讨神经肽Y(NPY)在单纯性肥胖儿童血浆中的水平及NPY水平与体重的关系.方法:选择50名5～12岁单纯性肥胖儿童和50名正常体重儿童,用放免法测定血浆NPY水平,比较肥胖组与对照组之间NPY水平的差异性.结果: 单纯性肥胖组血浆NPY水平(174.64±38.25)pg/mL明显高于对照组(128.69±32.65)pg/mL,且血浆NPY水平随体重增高而增高,男、女组间无差异.结论: NPY在单纯性肥胖儿童血浆中明显升高,其在单纯性肥胖症的发生、发展中可能起重要作用.     

氟桂利嗪治疗偏头痛及对血浆神经肽Y的影响

目的 :观察氟桂利嗪治疗偏头痛的疗效及其对血浆神经肽Y (NPY)水平的影响。方法 :选择偏头痛病人 6 0例 ,随机分为 2组 ,分别予氟桂利嗪和普萘洛尔治疗 ,观察 2组疗效。并分别测定治疗前后血浆NPY水平 ,做统计学分析。结果 :2组比较 ,氟桂利嗪组与普萘洛尔组偏头痛控制率 (5 4 % ,2 1% )及总有效率 (93% ,71% )的差异有显著意义(均P <0 .0 5 )。治疗后 ,氟桂利嗪组NPY水平降低了 (32± 5 3)ng·L- 1,经t检验 ,差异有显著意义 (P<0 .0 5 ) ,而普萘洛尔组差异无显著意义 (P >0 .0 5 )。结论 :氟桂利嗪治疗偏头痛有效 ,且治疗后血浆神经肽水平降低 ,提示氟桂利嗪可有解除血管痉挛的作用     

哮喘儿童血浆神经肽Y与心率变异性相关性分析

目的 探讨哮喘儿童血浆神经肽Y（NPY）含量与其心率变异性（HRV）的关系。方法 随机选择哮喘儿童35例与健康儿童40例测定其空腹血浆NPY浓度，同时做24h动态心电图并进行HRV时域分析。结果 HRV中反映迷走神经张力指标的高频（HF）、rMSSD和pNN50在哮喘儿童组数值明显高于正常对照组（P〈0．01），而反映交感神经张力的主要指标低频（LF）、SDNN和SDANN则明显低于对照组。哮喘儿童血浆NPY明显升高（P〈0．01），NPY与rMSSD（r=0．76）、pNN50（r=0．71）呈正相关。结论 哮喘儿童血浆NPY与其HRV密切相关。     

Effects of chronic beta-adrenoceptor antagonism on plasma catecholamines and blood pressure in hypertension

Plasma catecholamines were measured before and after treatment with beta-adrenoceptor antagonists in 17 hypertensive patients. Chronic treatment with beta-adrenoceptor antagonists caused substantial reductions in heart rate and intra-arterial blood pressure recorded continuously during ambulation. Before treatment, a quantitative relationship was observed between plasma norepinephrine and blood pressure and heart rate during a variety of activities; a similar relationship was also observed after chronic treatment five of six patients, suggesting that plasma norepinephrine remains an index of sympathetic activity despite the influence of beta-adrenoceptor antagonism. After treatment, plasma norepinephrine tended to be higher at any level of blood pressure, although not significantly so. Chronic treatment caused no significant change in mean resting plasma levels of norepinephrine and epinephrine. During exercise, plasma norepinephrine and epinephrine levels were significantly elevated above control after acute but not after chronic treatment. These observations do not support the hypothesis that beta-adrenoceptor antagonist drugs lower blood pressure in hypertensive man through a sympatholytic mechanism in he central nervous system or at peripheral presynaptic receptors.     

Modulation of feeding and drinking behaviour by catecholamines injected into nucleus caudatus in rats

Lesions of nucleus caudatus have been documented to produce adipsia and aphasia in rats. Injection of dopamine into this nucleus has been shown to facilitate water intake in rats. But, reports are not available on the effects of intracerebral injection of epinephrine and norepinephrine on feeding and drinking behaviour in animal models. Therefore, in the present study the effect of adrenaline and noradrenaline injected into nucleus caudatus on food and water intake in rats was assessed. 24 h basal food and water intakes were recorded in Wistar rats and were found to be 12.37 +/- 0.20 g and 22.04 +/- 0.27 ml respectively. Stainless steel cannulae were implanted stereotaxically into the nucleus caudatus. Four different doses (0.1 microgram, 0.5 microgram, 1 microgram, and 2 micrograms) of adrenaline and noradrenaline were injected into the nucleus caudatus through the implanted cannulae in separate groups of animals and their 24 h food and water intakes were recorded following these injections. No change in food and water intake was observed following the administration of different doses of adrenaline. A significant increase in 24 h food intake reaching a maximum of 16.03 +/- 0.15 g at 2 micrograms dose, without change in water intake was observed following administration of different doses of noradrenaline. The noradrenaline-facilitated food intake was blocked when noradrenaline was injected following injection of phentolamine, an alpha-receptor blocker. The bilateral lesions of nucleus caudatus resulted in a significant and sustained inhibition of food (8.98 +/- 0.17 g) and water intake (19.12 +/- 0.16 ml). These observations suggest that nucleus caudatus is involved in regulation of food and water intakes in rats. Noradrenaline-facilitated food intake is mediated by alpha-receptors. Adrenaline does not affect these ingestive behaviours when injected into the nucleus caudatus in rats.     

Modulation of feeding and drinking behaviour by catecholamines injected into nucleus accumbens in rats

Nucleus accumbens is proposed as one of the centers in the neural circuitry involved in the regulation of feeding and drinking behaviour in rats. Injection of dopamine and angiotensin-II into this nucleus has been documented to affect water and food intake in rats. Reports on the effect of intracerebral injection of catecholamines on feeding and drinking behaviour in animal models are conflicting. Therefore, in the present study the effect of adrenaline and noradrenaline injected into nucleus accumbens on food and water intake in rats was assessed. 24 h basal food and water intakes were recorded in Wistar rats and were found to be 12.3 +/- 0.46 g and 21.7 +/- 1.03 ml respectively. Stainless steel cannulae were implanted stereotaxically into the nucleus accumbens. Four different doses (0.1 microgram, 0.5 microgram, 1 microgram, and 2 micrograms) of adrenaline and noradrenaline were injected into the nucleus accumbens through the implanted cannulae in different group of animals and their 24 h food and water intakes were recorded following these injections. No change in food and water intake was observed following the administration of different doses of adrenaline. A significant increase in 24 h water intake reaching a maximum of 28.88 +/- 1.45 ml at 1 microgram dose, without change in food intake was observed following administration of different doses of noradrenaline. The noradrenaline-facilitated water intake was blocked when noradrenaline was injected following injection of phentolamine, an alpha-receptor blocker. The bilateral lesions of nucleus accumbens resulted in a significant and sustained inhibition of water intake (16.61 +/- 0.67 ml) without change in food intake. These observations suggest that noradrenaline facilitates water intake without affecting food intake when injected into the nucleus accumbens in rats and the dipsogenic effect of noradrenaline is mediated by alpha-receptors. Adrenaline does not affect these ingestive behaviours when injected into the nucleus accumbens in rats.     

Biphasic blood pressure response to neuropeptide Y in anesthetized rats

The effects of neuropeptide Y (NPY) on systemic arterial blood pressure and heart rate were studied in anesthetized intact and pithed rats. I.v. doses of NPY (0.3-30 nmol/kg) raised the mean arterial blood pressure dose dependently. At doses of greater than or equal to 3.0 nmol/kg, the initial pressor response was followed by a dose-dependent fall in blood pressure in intact and pithed rats. The depressor response was accompanied 1-2 min after the NPY injection by a slight increase in heart rate in pithed rats but not in intact rats, and 10 min after the injection by a decrease in heart rate in intact rats. After repeated injections of NPY, the depressor effect vanished, whereas the integrated pressor response over time was markedly enhanced. After pretreatment with the histamine H1-receptor antagonist, mepyramine, or with the histamine liberator, compound 48/80, the pressor response to NPY remained but the depressor response disappeared. We suggest that the marked fall in blood pressure can be attributed to NPY-evoked histamine release from mast cells.     

The involvement of neuropeptide Y Y1 receptors in the blood pressure baroreflex: studies with BIBP 3226 and BIBO 3304.

To ascertain the role of the neuropeptide Y Y1 receptors in the vascular manifestations of the sympathetic baroreflex, 10-s bilateral carotid occlusions were performed in anesthetized cats; systemic blood pressure was monitored continually. This maneuver rose systolic blood pressure in 23 +/- 2 mmHg. Following 100 microg/kg BIBP 3226 or BIBO 3304 i.v., the increase in blood pressure elicited by the occlusions was only 14 +/- 1 and 15 mmHg, respectively. Both BIBP 3226 and BIBO 3304 displaced significantly 5.5 fold rightward the pressor dose-response curve elicited by exogenous neuropeptide Y, without altering the norepinephrine curve. Prazosin (10 microg/kg) reduced the pressor response elicited by the carotid occlusion to 12 +/- 4 mmHg. The simultaneous administration of BIBP 3226 plus prazosin rose the systemic blood pressure following the occlusion only 9 +/- 2 mmHg, supporting the involvement of neuropeptide Y in vascular sympathetic reflexes.     

Clozapine decreases neuropeptide Y-like immunoreactivity and neuropeptide Y mRNA levels in rat nucleus accumbens.

The aim of this study was to evaluate the effect of acute, subchronic (14 days) and chronic (28 days) intraperitoneal (i.p.) administration of clozapine (10 or 25 mg/kg) on neuropeptide Y (NPY) system activity in the nucleus accumbens of the rat. NPY-like immunoreactivity (NPY-LI) decreased 24 h after subchronic clozapine while NPY mRNA after both acute and subchronic clozapine treatment. NPY-LI levels were also reduced 8 days after cessation of chronic lower-dose treatment. Subchronic (14 days) administration of the 5-HT2A antagonist ketanserin (1 mg/kg i.p.) or the dopamine D2/D3 antagonist (+/-) sulpiride (100 mg/kg i.p.) reduced NPY-LI levels, whereas the dopamine D1-like antagonist SCH 23390 (0.5 mg/kg i.p.), dopamine D4 antagonist L-745,870 (1 mg/kg per os), and alpha1-adrenergic antagonist prazosin (0.2 mg/kg i.p.) had no effect. There were no significant differences between the ketanserin-induced decrease in NPY-LI levels and the effects of the following two-drug combinations: ketanserin and SCH 23390, ketanserin and L-745,870, and ketanserin and prazosin. The study has shown that clozapine reduces NPY system activity in the rat nucleus accumbens. It seems that the action of clozapine is partly mediated by blockade of 5-HT2A and D2/D3 dopaminergic receptors.     

Effects of neuropeptide Y on mean circulatory filling pressure in intact and ganglionic-blocked conscious rats.

The dose-response effects of neuropeptide Y (NPY) and the vehicle, 0.9% NaCl, on mean arterial pressure (MAP), heart rate (HR) and mean circulatory filling pressure (MCFP), an index of body venous tone, were examined in conscious, intact and hexamethonium-treated rats. Saline infusions in intact and hexamethonium-treated rats did not significantly affect MAP, HR and MCFP. The i.v. infusion of NPY in intact rats dose dependently increased MAP, decreased HR, but did not alter MCFP. In the presence of hexamethonium, the pressor effect of NPY was enhanced, the lack of MCFP effect remained and the bradycardic effect was markedly attenuated. Our results suggest that NPY has moderate effects on MAP, but negligible effects on body venous tone.     

Effect of pinacidil on blood pressure,plasma catecholamines and plasma renin activity in essential hypertension

Summary Pinacidil, a new cyanoguanidine derivative, is an antihypertensive agent with arteriolar vasodilating properties, which acts on precapillary resistance vessels. A trial was carried out in 30 patients with essential hypertension WHO I-II. The treatment period was divided into three phases. Hydrochlorothiazide (HCTZ) and amiloride were administered for 4 weeks in Phase 1 and supine and standing blood pressure decreased significantly. During Phase 2 pinacidil was added to HCTZ/amiloride for the following 3 months. A further significant reduction in blood pressure was obtained. In the next period of treatment (Phase 3) patients were divided into two groups. For 1 month Group A (15 patients) received pinacidil alone and Group B (15 patients) received HCTZ/amiloride. Conventional laboratory blood tests in all patients remained unchanged during treatment. Reported side effects during Phase 2 were headache (2 patients), dizziness (3 patients), palpitations (2 patients) and ankle oedema (2 patients). Plasma renin activity was slightly increased at the end both of Phases 1 and 2. Plasma catecholamines were increased but not significantly at the end of Phase 2 as compared to Phase 1. The results indicate that pinacidil is effective in lowering blood pressure in mild to moderate essential hypertension.     

Effects of azepexole on blood pressure, pulse rate, plasma renin activity and urinary catecholamines in normotensive subjects

Single 5 mg oral doses of azepexole were administered to 6 normotensive male volunteers. Effects on blood pressure and pulse rate were recorded with the subjects supine, erect and during exercise for 8 hours after drug ingestion. Plasma renin activity and urinary catecholamine excretion were measured before and after treatment. Blood pressure was reduced when supine, erect and during exercise. The maximum reduction in systolic and diastolic blood pressure was 20.7 mmHg and 7.9 mmHg, respectively. There was a small reduction in the pulse rate when supine, significant from 2 to 3 hours after drug ingestion. Plasma renin activity increased significantly with drug treatment. There was an insignificant trend towards a reduced urinary catecholamine excretion. Only 1 subject developed significant side-effects. The similarity of azepexole to clonidine is discussed. It is considered that azepexole warrants further study as a hypotensive drug.