Brain natriuretic peptide enhances the endothelium-independent cAMP and vasorelaxant responses of calcitonin gene-related peptide in rat aorta

Calcitonin gene-related peptide (CGRP) causes vasorelaxation in rat aorta involving endothelium/nitric oxide (NO)-dependent elevations of both cAMP and cGMP levels. When endothelium is removed, preincubation with exogenous NO uncovers and potentiates direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP. This enhancing effect of NO potentially involves elevation of cGMP and inhibition of Type III (cGMPinhibitable) phosphodiesterase, causing accumulation of cAMP. However, NO may have other actions. The aim of the present study was to determine if brain natriuretic peptide (BNP), which elevates cGMP levels independent of NO, could enhance cAMP accumulations and vasorelaxations induced by CGRP in rat aortic rings denuded of endothelium. When added separately, neither CGRP (100 nM) nor BNP (10 nM) altered cAMP levels. When added in combination, CGRP (100 nM) and BNP (10 nM) significantly elevated cAMP levels (from control of 0.95 ± 0.08 to 1.53 ± 0.09 pmol/mg protein) at 2 min. BNP (10 nM) elevated cGMP levels 10-fold at 2 min and this response was not altered by co-administration of CGRP (100 nM).Pretreatment with BNP at concentrations as low as 1 nM in endothelium-denuded aortic rings greatly enhanced the direct vasorelaxant effects of CGRP (100 nM) (from control of 0% to 57.6 ± 6.8% relaxation of phenylephrineprecontractions). Our findings indicate that BNP enhances direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP in rat aorta, thus supporting the concept that cGMP inhibits cAMP metabolism and enhances CGRP-induced responses in aortic smooth muscle cells.     

Behavioral, biochemical and neurotoxicological actions of the alpha-ethyl homologue of p-chloroamphetamine

The present set of experiments was designed to examine the effects of extension of the alpha-methyl of p-chloroamphetamine (PCA) to an alpha-ethyl. Therefore, the alpha-ethyl homologue of PCA, 1-(4-chlorophenyl)-2-aminobutane (CAB), was compared to PCA in a number of pharmacological assays. CAB was 2-fold less potent than PCA at inhibiting synaptosomal uptake of [3H]5-hydroxytryptamine ([3H]5-HT), and 5-fold less potent at inhibiting uptake of [3H]dopamine ([3H]DA). In drug discrimination assays, CAB was approximately 3-fold less potent than PCA in animals trained to discriminate 3,4-methylenedioxymethamphetamine (MDMA) or its alpha-ethyl homologue, S-(+)-N-methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (S-(+)-MBDB), from saline. Monitoring with in vivo microdialysis, 10 mg/kg of PCA caused a large increase in extracellular DA and a significant decrease in 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum. In contrast, 11 mg/kg CAB caused no increase and 22 mg/kg CAB caused only a slight increase in extracellular DA. Both doses of CAB caused a decrease in extracellular DOPAC. The potential 5-HT neurotoxicity of CAB was examined by measuring monoamine and metabolite levels and [3H]paroxetine binding at one week following acute doses. A 10 mg/kg dose of PCA caused an 80% decrease in cortical and hippocampal serotonergic markers, while an equimolar dose of CAB decreased only hippocampal 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels. However, 22 mg/kg of CAB produced a 20-40% decrease in all serotonergic markers. Thus, extension of the alpha-alkyl significantly decreases the dopaminergic effects of PCA. The similar decrease in relative 5-HT neurotoxicity and the decreased ability to alter dopaminergic systems in vivo and in vitro supports the involvement of DA in the neurotoxicity of PCA.     

钙拮抗剂TMB-8抑制BHQ,NE和KCl引起的培养乳牛基底动脉单个平滑肌细胞内游离钙的升高

用AR CM MIC阳离子测定系统,测量单个细胞内游离钙浓度([Ca²⁺]i),研究8-(N,N-二乙胺)-n-辛基 3,4,5-三甲氧基苯甲酸酯(TMB-8)对培养乳牛基底动脉平滑肌[Ca²⁺]i的作用。在细胞外钙浓度为1.3mmol·L^-1时,TMB-8(30μmol·L^-1)可明显抑制BHQ,NE及KCl引起[Ca²⁺]i的升高。在细胞外钙为零+EGTA 0.1mmol·L^-1时,TMB-8(10,30及100μmol·L^-1)可浓度依赖性地降低静息[Ca²⁺]i,TMB-8(30μmol·L^-1)可几乎完全阻断BHQ及NE引起[Ca²⁺]i的增加。研究表明TMB-8降低培养乳牛基底动脉平滑肌[Ca²⁺]i的机制,主要是抑制肌浆网Ca²⁺的释放,或增加肌浆网对Ca²⁺的摄入,并由此间接地抑制细胞外钙的内流。     

多囊卵巢综合征患者卵巢间质胰岛素样生长因子受体的表达

目的：探讨肥胖及非肥胖多囊卵巢综合征（ＰＣＯＳ）患者卵巢间质胰岛素样生长因子（ＩＧＦ－Ⅰ）受体基因的定量表达。方法：用逆转录基因扩增技术（ＲＴ－ＰＣＲ），检测３５例ＰＣＯＳ患者（肥胖组１５例，非肥胖组２０例）及２０例正常妇女（对照组）卵巢间质细胞ＩＧＦ－Ⅰ受体ｍＲＮＡ的表达量（灰度比值）。并对ＩＧＦ－Ⅰ受体基因ｍＲＮＡ逆转录的ｃＤＮＡ产物进行限制性内切酶酶切分析。结果：ＰＣＯＳ两组ＩＧＦ－Ⅰ受体基因的表达量显著高于对照组，ＰＣＯＳ两组灰度比值为１．１８４±０．２４０，对照组灰度比值为０．９９９±０．０８６（Ｐ＜０．００１）。非肥胖组（１．２３８±０．３８７）明显大于肥胖组（１．０５８±０．１０９，Ｐ＜０．１）。酶切分析证实，３组ＩＧＦ－Ⅰ受体基因扩增片段相同，ＰＣＯＳ两组未发现明显的碱基突变存在。结论：ＰＣＯＳ患者卵巢间质ＩＧＦ－Ⅰ受体基因呈过度表达。且ＰＣＯＳ非肥胖患者局部ＩＧＦ－Ｉ受体表达高于ＰＣＯＳ肥胖患者。     

纤维支气管镜胸膜腔检查对原因不明胸腔积液的诊断价值

为评价纤维支所管镜行胸膜检查在诊断原因不明胸腔积液中的价值，用纤维支气管镜对１０例原因不明的胸腔积液患者进行胸腔检查。结果９例２检查后明确了病因，且无并发症，提示该法对于不明胸腔积液的诊断是一种阳性率高、安全、简便的检查方法。     

Reizhusten, Belastungsdyspnoe und zystische Lungenveränderungen bei einem 28jährigen Patienten

Zusammenfassung Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische Hilfestellung. Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden. Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung sowie den Verlauf bestimmt.     

A preliminary study of the changes in the direct-acting mutagenicities of several nitropolycyclic aromatic hydrocarbons after exposure under sunlight

Five commercially available nitropolyclyclic aromatic hydrocarbons (nitro-PAH), namely, 4-nitrobiphenyl, 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene, and 2,7-dinitrofluorene, were exposed under restricted sunlight in the open air. The direct-acting mutagenicities of the samples after an exposure of 45 days were measured in order to compare them with those of the original samples in the Ames Salmonella typhimurium bioassay. It was found that the mutagenicities of some nitro-PAH do not change significantly while the mutagenicities of others increase or decrease after exposure. A preliminary study of nitro-PAH reaction products after exposure using GC, GC/MS, and FT-IR is also reported.     

高龄初产妊高征孕妇过氧化反应的研究

目的：探讨高龄初产妊高征孕妇体内过氧化反应。方法：测定正常初产妇、妊高征孕妇妊娠晚期母血过氧化脂质（LPO）、超氧化物歧化酶（DOD）的含量。结果：1．高龄初产妇母血LPO较非高龄初产妇明显升高，SOD明显下降，P＜0．05。孕妇年龄与母血LPO呈明显正相关，与SOD呈明显负相关，P均＜0．05。2．妊高征孕妇LPO较正常孕妇显著增高，SOD显著下降，P＜0．05，并随病情加重LPO水平升高、SOD水平下降更为显著，P＜0．05。3．高龄初产妊高征孕妇母血LPO含量较非高龄初产妊高征孕妇明显增高，P＜0．05，而SOD则无显著变化，P＞0．05。4.妊高征孕妇胎儿宫内生长发育迟缓（IUGR）发生率较正常孕妇显著升高，P＜0．025，各组脐血清LPO、SOD含量无显著差异，P＜0．05。结论：高龄初产妊高征孕妇体内过氧化作用明显增强，LPO水平的升高可能为高龄初产妇妊高征发生率及IUGR发生率增加的原因之一。