Hunzicker-Dunn M
J Biol Chem. 1981 Dec 10;256(23):12185-93.
The magnitude of activation of the type I and type II forms of cAMP-dependent protein kinase was investigated in estrous follicles and corpora lutea (CL) obtained from ovaries of control rabbits and rabbits injected acutely with human chorionic gonadotropin (hCG). To this end, a chromatographic technique which permitted quantitative evaluation of the in vivo activational state of the two forms of cAmP-dependent protein kinase was developed and verified. Results revealed that in follicles obtained from ovaries of untreated estrous rabbits, 15% of the soluble cAMP-dependent protein kinase, all of which exists as the type II isozyme, is activated. Intravenous administration of a single bolus of hCG promoted a concentration-dependent activation (in 10 min) of this protein kinase isozyme. In CL obtained from ovaries of control, 4-day pseudopregnant rabbits, 32% of the total soluble cAMP-dependent protein kinase exists as the type I form and 68% exists as the type II form. Both types of protein kinase are approximately 10% dissociated in CL from ovaries of untreated rabbits. Upon intravenous administration of hCG, only the type I form of cAMP-dependent protein kinase is further activated (in 10 min). Dissociation of this protein kinase is dependent upon the time and concentration of hCG. Preferential activation of the type I form of cAMP-dependent protein kinase in CL is also demonstrable in in vitro studies using exogenous cAMP. These data suggest that the physiological intracellular mediator of acute cAMP-regulated, hCG-triggered functions in rabbit ovarian follicles is the type II isozyme of cAMP-dependent protein kinase while in CL of 4-day pseudopregnant rabbits, it is the type I enzyme form.
研究了从对照兔和急性注射人绒毛膜促性腺激素（hCG）的兔卵巢中获得的动情期卵泡和黄体（CL）中I型和II型环磷酸腺苷（cAMP）依赖性蛋白激酶的激活程度。为此，开发并验证了一种色谱技术，该技术可对两种形式的cAMP依赖性蛋白激酶的体内激活状态进行定量评估。结果显示，从未经处理的动情期兔卵巢中获得的卵泡中，15%的可溶性cAMP依赖性蛋白激酶（均以II型同工酶形式存在）被激活。静脉注射单次大剂量hCG可促进该蛋白激酶同工酶的浓度依赖性激活（10分钟内）。在从对照的4天假孕兔卵巢中获得的CL中，总可溶性cAMP依赖性蛋白激酶的32%以I型形式存在，68%以II型形式存在。在未经处理的兔卵巢CL中，两种类型的蛋白激酶均约有10%解离。静脉注射hCG后，只有I型cAMP依赖性蛋白激酶被进一步激活（10分钟内）。该蛋白激酶的解离取决于hCG的时间和浓度。在使用外源性cAMP的体外研究中，也证实了CL中I型cAMP依赖性蛋白激酶的优先激活。这些数据表明，兔卵巢卵泡中急性cAMP调节的、hCG触发功能的生理细胞内介质是cAMP依赖性蛋白激酶的II型同工酶，而在4天假孕兔的CL中，是I型酶形式。
