钙调素抗体的制备和鉴定

将从猪脑中所得SDS—PAGE纯的钙调素进行化学修饰,得(DNPm—CaM)n—BSA。将此修饰物免疫California白兔得抗血清。钙调素的ELISA测定表明:抗血清与天然牛脑和天然猪脑钙调素、CaBP_(72)(钙结合蛋白,分子量72KDa)、CaN(神经钙蛋白)、TnI(肌钙蛋白抑制亚单位)的交叉反应率分别为100％、100％、0.7％、0.4％、0.02％;与CaBP_(11)、CaBP_(12)、TnT、TnC、S—100、MLC(肌球蛋白轻链)均无交叉反应。免疫转移鉴定技术示:大鼠脑匀浆上清液显示强弱两条区带,强染色带相当于钙调素的位置,弱显色带分子量小于钙调素;其它所测大鼠组织匀浆上清液只在钙调素位置显示单一区带。     

Pentylenetetrazole-induced bursting activity and cellular protein phosphorylation in snail neurons

To elucidate the intracellular mechanism of seizure discharge, phosphorylation of cellular protein during pentylenetetrazole (PTZ)-induced bursting activity in snail neurons was investigated. PTZ markedly enhanced the phosphorylation of proteins of 34,000 and 50,000 molecular weight. Similar effects were observed by application of a calcium ionophore, A23187. Calmodulin antagonist, N-(6-aminohexyl)-5-chloronaphthalenesulfonamide hydrochloride (W-7), inhibited the PTZ-induced increased phosphorylation of these two proteins. Dibutyryl cyclic AMP and iosobutylmethylxanthine (IBMX) showed no significant effect on the phosphorylation pattern. Bath application of the calcium ionophore produced bursting activity followed by long-lasting hyperpolarization. Bath application of W-7 completely inhibited the PTZ-induced bursting activity. These results suggest that the phosphorylation of proteins of 34,000 and 50,000 in molecular weight is related to the generation of bursting activity by PTZ.     

镉对人体外周血淋巴细胞内游离Ca~(2+)及钙调素影响的研究

采用体外实验方法，观察CdCl2对培养24h的人外周血淋巴细胞内游离Ga2+浓度及CaM活性的影响。结果表明：细胞内游离Ca2+浓度与镉浓度（≤100μmol／L）及染毒时间（≤60min）存在明显的剂量及时相相关，在≤50μmol／LCdCl2作用下，CaM活性随染毒剂量增加而升高，50μmol／LCdCl2使CaM活性增至0μmol／L组的190．22％（P＜0．05），但100μmol／LCaCl2则对CaM无激活作用。在一定镉浓度（0～50μmol／LCdCl2）及染毒时间（0～40min）内，细胞内游离Ca2+浓度与CaM活性呈*一致性变化，提示镉的免疫毒作用机制与Ca2+、CaM系统有关。     

豚鼠耳蜗螺旋神经节钙调素的分布

观察正常豚鼠耳蜗螺旋神经节钙调素的分布，因为作为真核细胞中最重要的Ｃａ＾２＋受体－－钙调素在听觉径路上的分布和功能尚未见报道。     

白芍总甙对大鼠腹腔巨噬细胞产生肿瘤坏死因子的调节机制

目的：研究不同浓度白芍总甙（ＴＧＰ）调节大鼠腹腔巨噬细胞（ＭΦ）产生肿瘤坏死因子（ＴＮＦ）作用。方法：在ＭΦ培养系统中有或无环氧酶抑制剂和钙调蛋白抑制剂等工具药，测定４５Ｃａ内流、ＰＧＥ２和ＴＮＦ含量。结果：ＴＧＰ（０．５～１０ｍｇ·Ｌ－１）明显促进ＬＰＳ诱导ＭΦ的４５Ｃａ内流和ＴＮＦ产生。线性回归分析表明，４５Ｃａ内流和ＴＮＦ产生呈明显正相关。三氟拉嗪（４０μｍｏｌ·Ｌ－１）可阻断ＴＧＰ促进ＬＰＳ诱导ＭΦ产生ＴＮＦ。ＴＧＰ－ＬＰＳ的ＴＮＦ释放曲线呈钟罩形，而ＴＧＰ－ＬＰＳ的ＰＧＥ２产生曲线呈浓度依赖性升高。当ＴＧＰ在低浓度（０．５～１２．５ｍｇ·Ｌ－１）时，ＴＮＦ与ＰＧＥ２产生明显正相关，而高浓度（１２．５～２５０ｍｇ·Ｌ－１）两者呈明显负相关。吲哚美辛（１０μｍｏｌ·Ｌ－１）可使ＴＮＦ量效曲线下降支消失，而Ｎω亚硝基－Ｌ－精氨酸（１５μｍｏｌ·Ｌ－１）对此无明显影响。结论：低浓度ＴＧＰ对ＴＮＦ产生上调作用可能与促进４５Ｃａ内流，提高钙调蛋白活性从而促进ＰＧＥ２分泌等有关，而高浓度下调作用是可能与ＭΦ自身产生大量ＰＧＥ２介导有关。     

Ⅱ型糖尿病患者血清钙调素活性的变化

目的探讨２型糖尿病（ＤＭ２）患者血清钙调素（ＣａＭ）活性的变化及其对治疗的反应。方法ＤＭ２患者２６例，行口服降糖药治疗８ｗｋ，采用依赖于Ｃａ２＋的磷酸二酯酶分析法测定治疗前后患者血清ＣａＭ的活性，并设立正常对照组２０例。结果与正常对照组相比，ＤＭ２患者血清ＣａＭ活性明显降低（分别为６３１．６０±１０４．３２μｇ·Ｌ－１和３９９．８１±６８．４１μｇ·Ｌ－１，Ｐ＜０．００１）；口服降糖药治疗可使患者血清ＣａＭ活性明显回升（４９６．６９±５７．９４μｇ·Ｌ－１），但仍未能恢复正常（与正常对照组相比，Ｐ＜０．００１）。结论ＤＭ２患者存在着明显的Ｃａ２＋－ＣａＭ系统的功能异常，此可能与糖尿病的发生机制有关。     

Calmodulin-dependent adenylate cyclase in rat retina and the response to dopamine

Adenylate cyclase activity from the rat neural retina was highly stimulated with Ca²⁺ and calmodulin. The retinal adenylate cyclase activity was also increased by dopamine, and the activation was not changed with or without Ca²⁺-calmodulin in fractions from the neural retina homogenate after sucrose density gradient centrifugation. The results suggest that the two regulation systems (i.e. dopamine and Ca²⁺-calmodulin) of adenylate cyclase in the rat retina appear to be independent.     

腈双吡啉对离体血管舒张的机理

腈双吡啉是从氨利酮与米利酮的合成衍生物中筛选出的强心扩血管药,离体实验表明它能拮抗高K~+、去甲肾上腺素(NE)收缩家兔主动脉环的作用,使NE,CaCl_2的量效曲线右移;在高浓度时降低最大收缩效应。它能增强钙调蛋白拮抗剂拮抗NE引起的家兔主动脉环收缩。结果表明它对NE收缩离体血管的量效曲线不同于选择性阻断α受体的药物妥拉唑啉的作用,也不同于典型的钙拮抗剂维拉帕米的作用,而可能是钙调蛋白的非竞争性拮抗剂。     

Topical W-7 inhibits ultraviolet radiation-induced melanogenesis in Skh:HR2 pigmented hairless mice

We studied the effect of N-(6-aminohexyl)-5-chloro-1-napthalenesulfonamide (W-7) on ultraviolet radiation (UVR)-induced melanogenesis (tanning) in Skh:HR2 pigmented hairless mice. Topically pretreated mice were exposed to subminimal edematogenic as well as edematogenic UVR doses to establish whether W-7-UVR-induced edema prophylaxis allows increased melanogenesis while preventing edema. Ultraviolet light-irradiated vehicle control animals developed visible tans; however, both W-7-treated groups failed to tan. Topical W-7 before UVR exposure inhibited UVR induction of dopa oxidase activity in melanocytes by 49% (P=0.029) and inhibited UVR-induced deposition of melanin in the epidermis by 88% (P=0.006). Topical W-7 blocked 23% of the UVR but this blockage could not account for the inhibition of dopa oxidase and melanization. We conclude that, in addition to preventing edema, W-7 inhibits UVR-induced melanogenesis, possibly by affecting Ca²⁺-calmodulin and/or protein kinase C-dependent processes.