α2-肾上腺素受体对大鼠肠系膜动脉床降钙素基因相关肽释放的调节作用

降钙素基因相关肽（CGRP）从感觉神经末梢的释放受多种机制的调节。本文在离体灌流的大鼠肠系膜动脉床组织上,利用药理学工具药,研究了α2-肾上腺素受体对CGRP的基础和内毒素刺激后释放的作用。结果发现,α2-受体激动剂UK14304（3×10－6mol／L）可以显著抑制CGRP的基础释放和内毒素（1～5μg／ml）刺激后的释放,抑制幅度为22％～42％;用α2-受体拮抗剂Yohimbine（10－5mol／L）可以完全阻断UK14304的作用。结果表明突触前α2-受体对CGRP从外周阻力血管组织的释放,尤其是内毒素刺激后的释放具有抑制作用,在内毒素休克晚期,α2-受体功能减低可能介导了外周组织CGRP的过量释放。     

大鼠内毒素血症不同时期血浆CGRP和背根神经节CGRP mRNA水平的变化

本文采用逆转录聚合酶链反应（RT－PCR）方法测定大鼠内毒素血症不同时期胸腰段背根神经节降钙素基因相关肽（CGRP）mRNA水平的改变,结合血浆CGRP水平的改变,以期全面了解大鼠内毒素血症不同时期CGRP释放与合成的变化。结果显示：注射内毒素（5mg／kg）后30min时,大鼠血浆CGRP开始增高,而背根神经节CGRPmRNA水平无明显变化;注射内毒素后3h时,血浆CGRP及背根神经节CGRPmRNA均明显增高．分别为142％和32％,8h时则进一步增高,分别为216％和85％。提示内毒素不仅刺激外周组织释放CGRP,而且还能通过某些机制激活背根神经节CGRPmRNA的转录,使CGRP合成增加,以作为CGRP大量释放的重要补充来源。     

糖尿病大鼠肠系膜动脉降钙素基因相关肽释放减少以及一氧化氮的作用

我们以前的工作已表明,内毒素可引起降钙素基因相关肽（ＣＧＲＰ）从大鼠肠系膜动脉床释放,此作用部分是通过一氧化氮介导的。我们在离体肠系膜动脉床研究了内毒素引起糖尿病大鼠ＣＣＲＰ释放的改变以及一氧化氮所起的作用。采用ＣＣＲＰ放射免疫分析法测定灌流液中ＣＣＲＰ含量,ＲＴ－ＰＣＲ法测定背根神经节ＣＧＲＰｍＲＮＡ水平。结果显示：内毒素累积灌流引起ＣＧＲＰ浓度依赖性地释放增多,此作用在糖尿病大鼠系膜动脉术明显     

肾上腺髓质素和降钙素基因相关肽受体在血管平滑肌细胞的脱敏—受体活性修饰蛋白的作用

新近研究发现,肾上腺髓质素（adrenomedullin,ADM)和降钙素基因相关肽（calcitonin gene-related peptide,CGRP)均能与降钙素受体样受体（calcitoni receptor-like receptor,CRLR)结合,其配体特异性由受体活性修饰蛋白（receptor activity-modifying protein RAMP)调控,本工作在离体培养的大鼠胸主动脉血管平滑肌细胞（vsacular smooth muscle cells,VSMCs)上观察ADM和CGRP受体脱敏现象,以探讨CRLR／RAMP假说在心血管组织方面的意义,用无血清培养基（serum-free medium,SFM)和含有10^-8mol/L ADM,CGRP和肾上腺髓素质前体原N－末端20肽（proadrenomedullin N-terminal 20 peptide PAMP）的SFM培养,再用10^-8mol/L ADM或 CGRP和磷酸二酯酶的抑制剂异丙基次黄苷（isobutyryl methyxanthine,IBMX)与VSMCs进行第二次孵育,然后收集细胞,测定VSMCs cAMP含量。10^-8mol/LADM,CGRP和PAMP单独与VSMCs孵育,VSMCs cAMP含量分别较SFM组高191％（P＜0．01）,385％（P＜0．01）和67％（P＜0．05）,预先用10^-8mol/L ADM ak CGRP与VSMCs孵育可降低随后的CGRP刺激VSMCs产生cAMP,分别较单次CGRP育少44％（P＜0．05）和48％（P＜0．01）,预先用100nmol/L蛋白激酶A（PKA）抑制剂H－89处理VSMCs,可完全阻断ADM和CGRP预处理诱导的第二次CGRP刺激的VSMCs cAMP含量减少,表明VSMCs对CGRP的脱敏过程是通过PKA途径实现的,预先用ADM,CGRP处理VSMCs后,用ADM第二次孵育,细胞内cAMP含量与单次ADM孵育无明显改变,PKA抑制H－89与VSMCs孵育,无论对欠ADM刺激或对ADM和CGRP处理的第二次刺激的cAMP生成均无影响,用PAMP处理VSMCs后,ADM和CGRP的第二次刺激的VSMCs cAMP水平无明显改变（P＞0．05）。结果提示,在离体培养的大鼠VSMCs,ADM epc wsg i euk txgtdmj CGRP受体对预先用ADM和CGRP处理后的激动剂的第二次刺激都脱敏,表明ADM和CGRP的脱敏现象不一致。     

八肽胆囊收缩素减轻肿瘤坏死因子诱导的离体兔肺动脉反应性变化及内皮细胞损伤

为探讨八肽胆囊收缩素（ＣＣＫ－８）缓解内毒素休克时肺动脉高压的作用机制,应用离体血管环张力测定技术及扫描电镜方法,观察了ＣＣＫ－８对肿瘤坏死因子α（ＴＮＦ－α）引起的肺动脉反应性及肺动脉内皮细胞超微结构变化的影响。结果显示：离体脑动脉经ＴＮＦ－α（４０００Ｕ／ｍｌ）孵育２ｈ对苯肾上腺素（ＰＥ）的收缩反应、对乙酰胆碱（ＡＣｈ）及硝普钠（ＳＮＰ）的内皮依赖性及非内皮依赖性舒张反应均无明显影响。ＴＮＦ－     

再投喂鱼油对瓦氏黄颡鱼肌肉脂肪酸组成的影响

为研究植物油替代鱼油对瓦氏黄颡鱼（Pelteobagrus vachelli）生长及肌肉脂肪组成的影响及重投喂鱼油对瓦氏黄颡鱼肌肉脂肪酸组成的影响,实验以大豆油分别替代饲料中的0（FO）、50（S1）、75（S2）和100%（SO）的鱼油配制等氮、等能的颗粒饲料,每组设置3个平行,养殖80d后,再投喂鱼油30d。结果表明,饲料中添加豆油不会显著影响瓦氏黄颡鱼的增重率、肝体指数和体成分（P>0.05）。随着饲料中大豆油含量的增加,S2和SO组肌肉中C18:1n-9、C18:2n-6和单不饱和脂肪酸比例显著增加（P < 0.05）,而C20:5n-3,C22:5n-3及n-3/n-6比例显著下降（P < 0.05）。再投喂鱼油30d后,SO组肌肉中C18:3n-6、C20:4n-6、Σ n-9、Σ n-6和S2组中C18:1n-9、Σ n-6比例显著下降（P < 0.05）,而S2和SO组肌肉中Σn-3多不饱和脂肪酸、C20:5n-3和C22:5n-3比例显著增加（P < 0.05）。在生产中,可采用先植物油饲料、后鱼油饲料的养殖方式提高瓦氏黄颡鱼肌肉品质（增加有益人类健康的多不饱和脂肪酸）。     

吴茱萸次碱软膏对小鼠尾部鳞片银屑病模型的治疗作用

目的：吴茱萸次碱（Rutaecarpa RUT）是芸香科植物吴茱萸的主要成分,它可激活辣椒素受体促进降钙素基因相关肽（CGRP） 等神经递质的释放来发挥药理作用。本实验的目的为观察吴茱萸次碱软膏对小鼠银屑病模型治疗作用。方法：通过药剂学方法制 成了不同浓度（2%, 5%, 10%）RUT 软膏,在小鼠尾部与背部银屑病模型给药14 天,观察小鼠尾部颗粒层形成的变化,给药结束后 取小鼠背部皮肤组织匀浆后采用放射免疫方法检测CGRP水平变化,并且取小鼠血浆检测CGRP水平变化。结果：不同浓度的吴 茱萸次碱软膏均能促进小鼠尾部颗粒层形成（P<0.05）,并且浓度为5%与10%的RUT 软膏能显著降低小鼠背部CGRP 含量（P<0. 05）,但是其对小鼠血浆的CGRP 没有影响。结论：吴茱萸次碱外用对小鼠银屑病模型有一定的治疗作用,这种作用与其促进小鼠 皮肤CGRP 释放而导致其含量降低有关。     

盾叶薯蓣离体成花的影响因素及组织学观察

研究了居群、外植体类型、激素、铁盐对盾叶薯蓣（Dioscorea zingberensis C．H．Wright）离体成花的影响,建立了从花序切段高效直接再生花序和小花的实验体系。以不同的培养基对5个居群盾叶薯蓣的花序进行离体培养,利用石蜡切片技术观察再生花序的发生。结果表明5个居群的盾叶薯蓣都能直接再生花序,与花器官相关组织的外植体均具有不同程度的花序再生能力。培养基的组成对离体花序诱导率有很大影响,BA促进形成花序,KT与高浓度的铁盐促进形成营养芽。其中,MS＋2．0mg／LBA＋0．2mg／LNAA最有利于花序再生及发育。切片观察表明,离体再生的花序主要发生于花序轴与花蕾交界处的苞片以及小花的花被片表层细胞。     

过氧亚硝基阴离子介导内毒素致肺血管损伤及胆囊收缩素的保护作用

本文探讨过氧亚硝基阴离子（ONOO^-）在内毒素致肺血管损伤中的介导作用和八肽胆囊收缩素（CCK）的保护作用及其机制。结果发现,内毒素主要成分脂多糖（LPS）可诱导大鼠肺组织生成ONOO^-1,ONOO^-能导致肺微血管壁通透性明显增加和肺脏严重病理变化;ONOO^-可引起离体肺动脉反应性异常改变,LPS也可产生类似变化;ONOO^-有较弱的舒血管作用并受到内皮细胞的抑制性调节;LPS诱导培养的牛肺动脉内皮细胞（BPAEC）产生增多的ONOO^-参与介导内皮细胞本身的损伤;CCK能拮抗LPS对BPAEC的损伤效应,此作用由CCK受体介导,并与抑制ONOO^-生成有关。结果提示,清除ONOO^-或减少ONOO^-生成可为防治内毒素引起的急性肺损伤等病理过程提供新对策;CCK是一种有应用前景的细胞保护因子。     

中药764—3对内毒素所致离体大鼠灌流肺损伤的保护作用探讨

本研究观察了大肠杆菌内毒素对大鼠离体灌流肺的氧化性损伤作用,并探讨了中药７６４－３对该损伤的保护作用。结果发现单纯离体灌流肺给予内毒素刺激未能引起肺动脉升高,这与在体情况下的反应不同。内毒素组的肺泡灌洗液中蛋白质含量和肺组织湿干重比值分别比其它组为高（Ｐ＜０．０５）,该组肺组织匀浆和肺泡灌洗液中丙二醛（ＭＤＡ）含量也显著高于其它组（Ｐ＜０．０１）。中药７６４－３能够显著地减轻肺水肿（Ｐ＜０．０５）     

Developmentally regulated expression of the calcitonin gene related peptide (CGRP) in rat lung endocrine cells

Calcitonin (CT) and the calcitonin gene-related peptide (CGRP) are generated by alternative RNA processing from a single CT/CGRP gene. Recently, we reported the existence of CGRP-immunoreactivity and CGRP mRNA in endocrine cells or Kulchitsky (K) cells of human and rat lung [Wada et al. 1987b]. In this report, an examination was made of developmental changes in the expression of the CGRP gene in rat lungs by immunohistochemistry, radioimmunoassay (RIA) and Northern hybridization. CGRP-positive K-cells in lung tissue appeared on the 18th day of gestation. Their number was greatest on the 20th day of gestation and then decreased postnatally. The level of CGRP in rat lung was found to be highest in a 1-day-old neonate by RIA. In the Northern hybridization of rat lung using the CGRP 3' non-coding region (exon 6) of the first human CT/CGRP gene as the probe, 1.0 kilobase (kb) CGRP mRNA was found to be abundant on the 20th day of gestation and in a 1 day-old neonate. It thus appears that CGRP in rat lung is essential for pulmonary adaptation at birth and/or from the last intrauterine stage to the early neonatal period.     

归辛颗粒对偏头痛大鼠行为症状及血浆中CGRP含量的影响

目的:研究归辛颗粒(GXG)对硝酸甘油诱发的实验性偏头痛大鼠行为症状及颈静脉血浆中降钙素基因相关肽(CGRP)含量的影响并探讨其可能的作用机制。方法:采用SD大鼠,GXG以大、中、小三个剂量灌胃给药7d后,皮下注射硝酸甘油诱发大鼠偏头痛模型,观察各组大鼠行为学差异并采用放射免疫法测定其颈静脉血浆中CGRP含量的变化。结果:GXG可显著改善大鼠的行为症状,颈静脉血浆中CGRP含量明显低于模型组,与模型组比较差异有统计学意义(P<0.05或P<0.01)。结论:GXG可能通过调节偏头痛大鼠血浆中CGRP的水平,改善脑血管舒缩功能障碍,起到减轻偏头痛的作用。     

Solubilization of binding sites for IAPP and CGRP from rat lung

Functional binding sites for [¹²⁵I]IAPP and [¹²⁵I]CGRP were solubilized from rat lung membranes with CHAPSO (10 mM). Rat IAPP had a higher affinity (K_i = 22.9 nM) for [¹²⁵I]IAPP binding and rat CGRP (K_i = 0.904 nM) had a higher affinity for [¹²⁵I]CGRP binding over related peptides. [¹²⁵I]IAPP binding was unaffected by GTPγS, but [¹²⁵I]CGRP binding was 50% inhibited, indicating solubilization of a G-protein-receptor complex for CGRP but not IAPP binding. Wheat germ agglutinin affinity columns gave a 25-fold purification of IAPP binding sites, but no CGRP binding sites were eluted from the column, indicating different patterns of glycosylation of the two sites.     

Calcitonin gene-related peptide (CGRP) in normotensive and spontaneously hypertensive rats

With the techniques of specific radioimmunoassay and gel filtration it was found that CGRP was distributed in various tissues of normotensive (WKY) and spontaneously hypertensive rats (SHR) with the highest concentration in the lumbar spinal cord (1197 +/- 94.8 pg/mg tissue) and the lowest in the auricle (15.0 +/- 2.1 pg/mg tissue). In comparison with WKY, CGRP concentration in the plasma was decreased and in the abdominal aorta and hypothalamus was increased in SHR. Gel filtration revealed only one major CGRP molecular form in the tissues. In addition, CGRP reduced the mean arterial pressure (MAP) in SHR in a dose-dependent manner. These data suggest that CGRP may play an important role in the pathogenesis of hypertension and its possible therapy.     

Circulating concentrations of calcitonin gene-related peptide (CGRP) in normal man determined with a new, highly sensitive radioimmunoassay

A highly sensitive and specific radioimmunoassay for human calcitonin gene-related peptide (CGRP) has been developed and used for determination of serum CGRP levels in 232 normal individuals, 123 females and 109 males, range of age 18 to 79 years. Mean serum concentration was 36.3 pmol/l +/- 6.2 (SD), and serum levels were unrelated to age and sex. The specificity of the assay was confirmed by gel chromatography, followed by HPLC analysis of extracts from normal serum using synthetic alpha- and beta-CGRP as standards.     

The role of calcium in endotoxin-induced release of calcitonin gene-related peptide (CGRP) from rat spinal cord

In the present study, the role of calcium in endotoxin-induced CGRP release was studied. 2 .5-50 μg/mL endotoxin and 1 -10 mmol/L caffeine caused concentration-dependent increase of CGRP release from rat spinal cord in vitro. However, no additive effect could he found when caffeine and endotoxin were concomitantly incubated. By using capsaicin, Ca2 -free medium, Omega-Conotoxin, nifedipine, W-7, ryanodine, MgCl2, Tris-ATP, rutheni-um red, the results indicate that the release of CGRP evoked by endotoxin from the sensory fibers of rat spinal cord is dependent on extracellular calcium. After entering into the cell through the N-type calcium channel, calcium binds to calmodulin, and triggers calcium release from intracellular calcium store by activating the caffeine-sensitive but ryan-odine-insensitive mechanism.     

Calcitonin and CGRP block bombesin- and substance P-induced increases in airway tone

Calcitonin gene-related peptide (CGRP) and calcitonin (C) are two peptides that are cocontained and probably coreleased with the potent bronchocontrictors, bombesin (B) and substance P (SP), within the lung. Although CGRP and C have a wide intrapulmonary distribution, their actions have not been well defined. By the use of a computerized lung mechanics analyzer, changes in response to 10-min infusions of these agents were measured in spontaneously breathing, anesthetized guinea pigs. Infusion of 0.3 nmol.kg-1.min-1 CGRP and 2 nmol.kg-1.min-1 C caused little change in lung mechanics. Infusion of 0.06 nmol.kg-1.min-1 B and 0.3 nmol.kg-1.min-1 SP caused a marked increase in inspiratory, expiratory, and total pulmonary resistance (RT), from base-line values (P less than 0.02), with a maximal effect at 10 min postinfusion (PI) [RT = 326 +/- 20% (SE) (B), 490 +/- 73% (SP)]. Coinfusion of C or CGRP with B or SP at the above concentrations caused a marked reduction in SP - [RT = 189 +/- 28% (C), 142 +/- 16% (CGRP) at 10 min PI] and B - [RT = 157 +/- 18% (C), 158 +/- 10% (CGRP) at 10 min PI] induced changes in resistance (P less than 0.015). The mode of action of C and CGRP is unknown, but these peptides may antagonize the effects of B and SP via autonomic pathways by interfering with B- or SP-induced changes in intracellular calcium concentrations or by increasing intracellular cAMP levels by binding to specific cellular receptors linked to adenylate cyclase.     

Amylin-induced suppression of ANP secretion through receptors for CGRP1 and salmon calcitonin

Amylin cosecretes with insulin from pancreatic beta-cells and shows high sequence homology with CGRP, adrenomedullin, and salmon calcitonin. This study aimed to investigate the effect of amylin on the atrial hemodynamics and ANP release from rat atria and to identify its receptor subtypes. Isolated perfused left atria from either control or streptozotocin-treated rats were paced at 1.3 Hz. The concentration of ANP was measured by radioimmunoassay and the translocation of ECF was measured by [3H]-inulin clearance. Rat amylin increased atrial contractility and suppressed the release of ANP. Rat CGRP showed similar effects but was approximately 300-fold more potent than amylin. Pretreatment with receptor antagonist for CGRP1 [rat alpha-CGRP (8-37)] or salmon calcitonin [acetyl-(Asn30, Tyr32)-calcitonin(8-32), (AC 187)] blocked the suppressive effect of ANP release and the positive inotropic effect by rat amylin. However, receptor antagonists for amylin [amylin (8-37), acetyl-amylin] did not block those effects. Amylin (8-37), acetyl-amylin, or rat alpha-CGRP (8-37) alone accentuated the release of ANP with no changes in atrial contractility. The effect of rat amylin and rat amylin (8-37) on the ANP release was attenuated in streptozotocin-treated rats. We suggest that amylin suppressed ANP release with increased atrial contractility through receptors for CGRP1 and salmon calcitonin and the attenuation of amylin and its antagonist on ANP release from streptozotocin-treated rat atria may be due to the downregulation of amylin receptor.     

炎症介质在内毒素引起大鼠肠系膜血管床降钙素基因相关肽释放中的作用

本研究在离体大鼠肠系膜血管床灌流模型上,采用特异放免法测定灌流液中的降钙素基因相关肽（ＣＧＲＰ）,观察几种常见炎症介质在内毒素引起ＣＧＲＰ释放中的作用。结果显示：前列腺素合成酶抑制剂地塞米松、布洛芬与消炎痛,缓激肽受体Ｂ２拮抗剂ＨＯＥ１４０,血小板激活因子拮抗剂ＷＥＢ２０８６,组胺Ｈ１受体拮抗剂苯海拉明以及和组胺Ｈ２受体拮抗剂西咪替丁,均能明显抑剂制内毒素引起的ＣＧＲＰ释放,５羟色胺受体拮抗剂ＩＣＳ２０５９３０却无明显作用。从而提示：内毒素引起ＣＧＲＰ释放是通过炎症介质前列腺素、缓激肽、血小板激活因子和组胺介导的,阻断或减少炎症介质的产生可望减轻内毒素血症时ＣＧＲＰ的过量释放。