Venkataraman B V, Ravishankar H N, Rao A V, Kalyani P, Sharada G, Namboodiri K, Gabor B, Ramasarma T
Department of Biochemistry, Indian Institute of Science, Bangalore, India.
Mol Cell Biochem. 1997 Apr;169(1-2):27-36. doi: 10.1023/a:1006882408983.
Decavanadate, an inorganic polymer of vanadate, produced contraction of rat aortic rings at a relatively high concentration compared to phenylephrine, an agonist of alpha-adrenergic receptor. This effect was blocked by two known alpha-adrenergic receptor antagonists, prazosin and phenoxybenzamine. Decavanadate, formed by possible dimerization of V5 under acid conditions, possessed a structural feature of two pairs of unshared oxygen atoms at a distance of 3.12 A, not found in its constituents of V4 or V5. A structural motif of O..O..O using such oxygen atoms is recognized in decavanadate. This matches with a similar motif of N..O..O that uses the essential amino and hydroxyl groups of the side-chain and the m-hydroxyl group in trans-beta form of noradrenaline. The interaction of such a structural motif with the membrane receptor is likely to be the basis of the unusual noradrenaline-mimic action of decavanadate.
十钒酸盐是钒酸盐的一种无机聚合物，与α-肾上腺素能受体激动剂去氧肾上腺素相比，它在相对较高的浓度下能使大鼠主动脉环收缩。这种效应被两种已知的α-肾上腺素能受体拮抗剂哌唑嗪和酚苄明阻断。十钒酸盐可能是在酸性条件下由V5二聚形成的，具有两对非共享氧原子，其间距为3.12 Å的结构特征，这在其V4或V5成分中未发现。在十钒酸盐中可识别出使用此类氧原子的O..O..O结构基序。这与使用去甲肾上腺素反式β形式侧链的必需氨基和羟基以及间羟基的类似N..O..O基序相匹配。这种结构基序与膜受体的相互作用可能是十钒酸盐异常的去甲肾上腺素模拟作用的基础。
