Eggena P, Ma C L, Fahrenholz F, Schwartz I L
Am J Physiol. 1985 Jul;249(1 Pt 1):C84-8. doi: 10.1152/ajpcell.1985.249.1.C84.
The effects of a photoaffinity label for arginine vasopressin receptors, [Phe2, Phe(p-N3)3]AVP (N3-AVP), on urea permeability and adenylate cyclase activity have been investigated in the toad urinary bladder. This compound, when activated by ultraviolet light, induced a maximal and persistent increase in the urea permeability of the intact bladder and a persistent increase in the adenylate cyclase activity of toad bladder epithelial cell homogenates. Covalent attachment of the analogue to target tissue during photolysis was equivalent at 4 and 20 degrees C. Bladders exposed to N3-AVP in the presence of AVP during photolysis were substantially less permeable to urea than controls that had been exposed to N3-AVP alone. These findings constitute further evidence in support of our previous suggestion that N3-AVP binds covalently to AVP receptors and, in addition, demonstrates that N3-AVP evokes a persistent increase in adenylate cyclase activity which, in turn, triggers a persistent increase in bladder permeability to urea.
已在蟾蜍膀胱中研究了精氨酸加压素受体的光亲和标记物[Phe2, Phe(p-N3)3]AVP（N3-AVP）对尿素通透性和腺苷酸环化酶活性的影响。该化合物在紫外线激活后，可使完整膀胱的尿素通透性出现最大且持续的增加，并使蟾蜍膀胱上皮细胞匀浆的腺苷酸环化酶活性持续升高。在光解过程中，类似物与靶组织的共价结合在4℃和20℃时相当。在光解过程中，于AVP存在的情况下暴露于N3-AVP的膀胱对尿素的通透性显著低于单独暴露于N3-AVP的对照。这些发现进一步证明了我们之前的推测，即N3-AVP与AVP受体共价结合，此外，还表明N3-AVP可引起腺苷酸环化酶活性的持续增加，进而引发膀胱对尿素通透性的持续增加。
