Mori M, Tsushima H, Matsuda T
Jpn J Pharmacol. 1986 Nov;42(3):361-9. doi: 10.1254/jjp.42.361.
Effects of dibutyryl-cyclic AMP (db-cAMP) and cyclic AMP (cAMP) microinjected into the hypothalamic supraoptic nucleus (SON) which contains the neurons synthesizing and releasing antidiuretic hormone upon the outflow and the osmotic pressure of urine and the other visceral functions were investigated in water-loaded rats anesthetized with ethanol. When microinjected into the SON the dibutyryl analog of cAMP induced dose-dependent antidiuretic effects without significant effects on any other visceral functions. Dibutyryl-cAMP was much more effective than cAMP; The ED50 value for db-cAMP was approx. 200 nmol versus more than 500 nmol for cAMP. The time course of the antidiuretic effects was relatively slow with minimal urine outflow appearing only after more than 1/2 hour post-injection. The effects induced by db-cAMP demonstrated tachyphylaxis and were partially inhibited by pretreatment with atropine or theophylline, which suggests that the antidiuretic effects were mediated through muscarinic and adenosine receptors present in the nucleus.
在用水合氯醛麻醉的水负荷大鼠中，研究了将二丁酰环磷腺苷（db-cAMP）和环磷腺苷（cAMP）微量注射到下丘脑视上核（SON）后对尿流量、渗透压及其他内脏功能的影响。视上核含有合成和释放抗利尿激素的神经元。当将cAMP的二丁酰类似物微量注射到视上核时，会产生剂量依赖性的抗利尿作用，而对任何其他内脏功能均无显著影响。二丁酰环磷腺苷比环磷腺苷有效得多；db-cAMP的半数有效剂量（ED50）约为200纳摩尔，而cAMP则超过500纳摩尔。抗利尿作用的时间进程相对较慢，仅在注射后半小时以上才出现最小尿流量。db-cAMP诱导的作用表现出快速耐受性，并且部分被阿托品或茶碱预处理所抑制，这表明抗利尿作用是通过视上核中存在的毒蕈碱和腺苷受体介导的。
