庆大霉素分泌过程的初步研究

应用恒温系统及缓冲液体系,考察了温度及pH值分泌过程的影响,然后在此基础上又讨论了添加葡萄糖、金属离子Fe^2 、K^ 和Mn^2 以及超声波和微波处理的效果,实验发现,pH＝7．4,温度34℃,以及添加5g／LKCl或50mg／LMnSO4都能刺激庆大霉素的分泌。     

Effect of Calcium on Spontaneous Quantal Transmitter Secretion from ACh-Loaded Myocytes

Introduction Transmitter secretion requires specialized secretory or- ganelles, the synaptic vesicles, for the packaging, stor- age, and exocytotic release of the transmitters[1,2]. The neurotransmitter acetylcholine (ACh) is released at the neuromuscular…     

Effects of gastric secretagogues on tissue glycerol in the isolated amphibian gastric mucosa

Summary Histamine and theophylline, two gastric secretagogues, significantly increased tissue glycerol content by 121 and 66%, respectively, in the isolated toad gastric mucosa. This is new evidence in favor of the hypothesis that gastric segretagogues may act via lipid mobilization.This investigation was supported by Consejo de Desarrollo Científico y humanístico de la Universidad del Zulia, Maracaibo, Venezuela.     

昆虫体外化学防御的研究

近年来,一些昆虫体外化学防御物质在分类学、医药、工业越来越得到广泛的应用,文章主要对昆虫外分泌物及其应用等作了一些探讨。     

Chemical analysis of the pheromone blends produced by males and females of the neotropical moth,Mocis megas (Guénée) (Lepidoptera,Noctuidae, Catocalinae)

Summary Pheromonal secretions produced by females and males of the noctuid moth,Mocis megas (Guénée) have been analyzed by gas chromatography and mass spectrometry (EI (electron impact) and CI (chemical ionization)). The female sex pheromone was a blend of (Z,Z,Z) 3,6,9 heneicosatriene (55%) and (Z,Z) 3,6-cis-9S, 10R-epoxyheneicosadiene (45%). Male secretion produced at the level of a prothoracic organ was a blend of two unsaturated major hydrocarbons: (Z,Z) 6,9 heneicosadiene, (64%) and (Z,Z,Z) 3,6,9 heneicosatriene (24%) and C₁₉, C₂₀ and C₂₂ homologues (total ratio 12%), as minor components. The trienic hydrocarbon was present in both sexes. The behavioral role of this male secretion has not yet been elucidated.     

SUR1基因多态性与磺脲类药物疗效的相关性

采用聚合酶链反应-限制性片段长度多态性技术检测了178例2型糖尿病和132例健康对照者磺脲类药物受体1(SURl)基因外显子16-3c／t多态性，并对其中112例糖尿病患者观察了磺脲类降糖药的疗效．与对照组相比，“t”等位基因频率和“tt”基因型(纯合子)在糖尿病组中的分布显著升高，“tt”基因型患者反映其胰岛素分泌功能的Homap指数较其他基因型(tc和cc)组显著降低，糖尿病中33例磺脲药治疗失效组t等位基因频率明显多于79例磺脲药治疗有效组．提示SURl基因变异可能导致2型糖尿病胰岛素分泌功能障碍，SUR1基因外显子16-3c／t多态性与磺脲类降糖药的疗效间存在连锁不平衡．     

Neuropeptide Y inhibits corticosterone secretion by isolated rat adrenocortical cells

Summary Studies with isolated rat adrenocortical cells have shown that neuropeptide Y (NPY) inhibits both basal and ACTH-stimulated corticosterone secretion. These results suggest the regulatory role of NPY in corticosterone secretion from the adrenal gland, especially during stress.Supported in part by a grant CPBP 06.03.3.16.     

嗜铬细胞分泌的模型研究

在大鼠肾上腺嗜铬细胞上应用全细胞膜片钳和膜电容检测技术，对细胞分泌的模型进行了研究．对Ｈｅｉｎｅｍａｎｎ等提出的准备释放库Ｂ，进行了更为精确深入的分析，提出了新的论据和修改内容．证实在距细胞膜 Ｃａ２＋通道３０ｎｍ处存在立即释放库，在距Ｃａ２＋通道３００ｎｍ处存在可释放库．通过内分泌细胞分泌模型分析了Ｃａ２＋的控制作用以及囊泡释放过程的时序特征．     

L-arginine and pancreatic islet blood flow in anesthetized rats

The aim of the present study was to see if L-arginine, which induces insulin release and is a precursor of the endothelial-derived relaxing factor nitric oxide, affects whole pancreatic and/or islet blood flow. For this purpose, anesthetized male Sprague-Dawley rats were injected intravenously with either saline or L-arginine (25, 100 or 250 mg/kg body weight). All doses of arginine caused a slight increase in blood glucose concentration, while the highest dose (250 mg/kg body weight) also increased insulin concentration. However, no changes in either mean arterial blood pressure, whole pancreatic or islet blood flow could be discerned with any of the doses of arginine used. It is concluded that insulin release is not necessarily associated with an increased islet blood perfusion.     

分泌载体pPSA18的构建及地衣杆菌淀粉酶在枯草杆菌中的表达和分泌

本文报道利用枯草杆菌噬菌体Spol 的启动子Spac Ⅰ,合成的解淀粉芽胞杆菌信号序列及枯草杆菌质粒PUB 18重组,构建分泌型表达载体并将地衣芽胞杆菌α-淀粉酶基因(缺失启动子及信号序列)引入构建的载体,获得重组质粒pPSA 18.将此质粒转化枯草杆菌QB1130(amy~-)感受态细胞,在含5μg/ml 卡那霉素及1%可溶性淀粉的LB 平板上筛选Km~r 及淀粉酶阳性的转化子.从阳性转化子中提取质粒,经酶切分析后重新转化枯草杆菌QB1130,得到的转化子全部都能向胞外分泌淀粉酶,证明构建的载体能在枯草杆菌中表达和分泌外源基因产物.