Imbert M, Chabardès D, Montegut M, Clique A, Morel F
Pflugers Arch. 1975 Jun 26;357(3-4):173-86. doi: 10.1007/BF00585973.
AVP dependent adenylate cyclase activity was measured in single pieces of 8 different tubular segments isolated from collagenase treated rabbit kidneys. High responses were observed in all the tested portions of the collecting tubule, that is its cortical branched part (BCT), its cortical straight part (CCT) and its outer medullary part (MCT). Dose response curves indicated in CCT: 2 fold threshold stimulation at 10(-11) M AVP, 27 fold stimulation at 10(-6) M AVP, half maximal stimulation at about 10(-9) M AVP. Both the medullary (MAL) and, to a lesser extent, the cortical (CAL) portions of the thick ascending limb were also observed to contain AVP sensitive adenylate cyclase (for MAL: 2 fold threshold stimulation at 10(-9) M AVP, 9 fold stimulation at 10(-7) M AVP, half maximal stimulation at 5 X 10(-9) M AVP). In contrast, nearly no responsiveness to AVP was observed in the proximal convoluted tubule, in the thin descending limb of the loop and in the distal convoluted tubule (DCT). The limited response obtained in DCT (which is a structure generally considered as a target site for AVP) as well as the clearcut effect elicited by AVP in MAL (the functioning of which is not known to be controlled by ADH) were expected observations; their possible physiological implications will be discussed.
在从经胶原酶处理的兔肾中分离出的8个不同肾小管节段的单个片段中，测定了血管加压素依赖性腺苷酸环化酶活性。在集合小管的所有测试部分，即其皮质分支部分（BCT）、皮质直部（CCT）和外髓部（MCT），均观察到高反应性。剂量反应曲线表明，在CCT中：在10（-11）M血管加压素时为2倍阈值刺激，在10（-6）M血管加压素时为27倍刺激，在约10（-9）M血管加压素时为半数最大刺激。还观察到厚壁升支的髓质部分（MAL）以及程度较轻的皮质部分（CAL）含有血管加压素敏感的腺苷酸环化酶（对于MAL：在10（-9）M血管加压素时为2倍阈值刺激，在10（-7）M血管加压素时为9倍刺激，在5×10（-9）M血管加压素时为半数最大刺激）。相比之下，在近端曲小管、髓袢细降支和远端曲小管（DCT）中几乎未观察到对血管加压素的反应性。在DCT中获得的有限反应（DCT通常被认为是血管加压素的靶位点）以及血管加压素在MAL中引发的明确效应（其功能未知受抗利尿激素控制）是预期的观察结果；将讨论它们可能的生理意义。
