Rodgers G M, Fisher J W, George W J
Am J Physiol. 1975 Nov;229(5):1387-92. doi: 10.1152/ajplegacy.1975.229.5.1387.
The regional distribution of cyclic AMP in the kidney was determined following erythropoietic stimulation with hypoxia and cobalt. Following these stimuli, increases in renal cyclic AMP concentrations were restricted to the cortex. The basis for this localization in the case of cobalt treatment was found to reside in the stimulation of renal cortical adenylate cyclase activity in vitro by concentrations of cobalt similar to those found in vivo. The level of cobalt in the cortex after cobalt treatment was found to approach 500 mumol/kg of tissue, whereas no detectable levels of cobalt were found in the renal medulla. Additionally, other agents such as parathyroid hormone and lactic acid, that are known to lack stimulatory effects on medullary adenylate cyclase, were found to stimulate the cortical enzyme. This stimulation of renal cortical adenylate cyclase correlates with enhanced erythropoiesis as demonstrated by increased radiolabeled iron incorporation into erythrocytes. These results support previous reports which suggest that renal cortical cyclic AMP mediates erythropoietin production in response to erythropoietically active agents.
在用低氧和钴进行促红细胞生成刺激后，测定了肾脏中环状AMP的区域分布。在这些刺激之后，肾脏环状AMP浓度的增加仅限于皮质。对于钴治疗而言，这种定位的基础在于，与体内发现的钴浓度相似的钴浓度在体外刺激了肾皮质腺苷酸环化酶活性。钴治疗后皮质中的钴水平接近500μmol/kg组织，而在肾髓质中未发现可检测到的钴水平。此外，已知对髓质腺苷酸环化酶缺乏刺激作用的其他物质，如甲状旁腺激素和乳酸，被发现可刺激皮质酶。肾皮质腺苷酸环化酶的这种刺激与红细胞生成增强相关，这通过红细胞中放射性标记铁掺入增加得到证明。这些结果支持了先前的报告，这些报告表明肾皮质环状AMP介导对促红细胞生成活性物质的促红细胞生成素产生。
