Intracelluar signal transduction of relaxin : comparative study with beta-adrenergic action

它的目的是如何松弛作用与cAMP和cGMP介导的作用相似和不同。取去卵巢大鼠注射苯甲酸雌二醇72小时后，取子宫纵行肌层。在无镁Krebs液中，电刺激可诱发时相收缩。当组织暴露在含15 mM镁的无钙40mX K溶液中时，[镁]i从对照溶液中的380微米增加到420微米。假设当暴露于0.6 mM的锰时，肌肉细胞内充满了锰。比较细胞内镁、锰负荷前后对松弛素、异丙肾上腺素、福司可林和环核苷酸衍生物的收缩反应。结果如下表所示。与异丙肾上腺素、Forsklin和松弛素相比，Mu(C)引起的细胞内Mg(B)升高对db cAMP和8-bromo cGMP引起的收缩抑制的影响。向上和向下箭头分别表示抑制作用的增强和减弱。蛋白激酶A的激活被认为是松弛素和肾上腺素能β作用的常见途径(Hsu和Sanborn，1986)。这些问题被提出，在细胞内锰负荷的影响下，松弛素和db cAMP如何以及为什么表现不同于异丙肾上腺素和Forsklin。

It was aimed how the relaxin action resembles and differs from cAMP-and cGMP-mediated effects. The longitudinal myometrium was taken from ovariectomized rat 72h after the injection of estradiol-benzoate. Phasic contractions were evoked in Mg-free Krebs solution by electrical stimulation. The [Mg]i was increased from 380muM in the control solution to 420muM, when the tissue was exposed to Ca-free 40mX K solution containing 15mM Mg. It was assumed that muscle cells were loaded with Mn, when exposed to 0.6mM Mn. Contractile responses to relaxin, isoprenaline, forskolin and cyclic nucleotide derivatives were compared before and after the intracellular load with Mg or Mn. Results are summarized in the table shown below.Influence of the elevation of intracellular Mg(b) of Mu(c) on the contractile inhibition caused by db cAMP and 8-bromo cGMP in comparison with that by isoprenaline, forskolin and relaxin. Upward and downward arrows indicate augmentation and attenuation of the inhibitory effects, respectively.The activation of protein kinase A is thought to be a common pathway of relaxin and adrenergic beta-action (Hsu and Sanborn, 1986). The questions are raised, how and why relaxin and db cAMP behabed differently from isoprenaline and forskolin under the influence of intracellular load with Mn.