Walkenbach R J, LeGrand R D, Barr R E
Invest Ophthalmol Vis Sci. 1980 Sep;19(9):1080-6.
The properties of adenylate cyclase from bovine and human corneal epithelium were investigated. Adrenergic drugs were the most effective stimulatory agents tested in bovine tissue, causing greater activation than did fluoride. Isoproterenol was the most potent agonist, followed by epinephrine and norepinephrine. Phenylephrine and dopamine also stimulated adenylate cyclase through beta-adrenergic receptors at relatively high concentrations. Enzyme stimulation by all the adrenergic drugs tested was completely inhibited by 1 microM propranolol or 0.1 microM timolol. The GTP analogue, GppNp, produced considerable activation and caused an augmented response when combined with isoproterenol, but not with fluoride. Prostaglandins E1, E2, or F2 alpha produced a small but significant stimulation over control which was not sensitive to propranolol inhibition. Adenylate cyclase from human corneal epithelium exhibited qualitatively similar characteristics to those of the bovine enzyme. Fluoride was the most effective stimulatory agent, followed by isoproterenol, phenylephrine, and dopamine. Prostaglandins failed to stimulate adenylate cyclase activity in human corneal epithelial preparations.
对牛和人角膜上皮的腺苷酸环化酶特性进行了研究。在牛组织中，肾上腺素能药物是所测试的最有效的刺激剂，其激活作用比氟化物更强。异丙肾上腺素是最有效的激动剂，其次是肾上腺素和去甲肾上腺素。苯肾上腺素和多巴胺在相对高浓度时也通过β-肾上腺素能受体刺激腺苷酸环化酶。所有测试的肾上腺素能药物对酶的刺激作用均被1微摩尔普萘洛尔或0.1微摩尔噻吗洛尔完全抑制。GTP类似物GppNp产生了相当大的激活作用，并且与异丙肾上腺素联合使用时会增强反应，但与氟化物联合使用时则不会。前列腺素E1、E2或F2α对对照产生了轻微但显著的刺激，且对普萘洛尔抑制不敏感。人角膜上皮的腺苷酸环化酶在性质上与牛酶的特征相似。氟化物是最有效的刺激剂，其次是异丙肾上腺素、苯肾上腺素和多巴胺。前列腺素未能刺激人角膜上皮制剂中的腺苷酸环化酶活性。
