Sears M, Mead A
Int Ophthalmol. 1983 Jun;6(3):201-12. doi: 10.1007/BF00141129.
There has been a suspicion on the part of many clinicians and research scientists that intraocular pressure can be regulated by neural and/or humoral influences upon the rate of aqueous humor formation. It has been difficult, if not impossible, to separate specific influences of the central nervous system upon intraocular pressure from vascular induced or other secondary alterations. The past two decades have witnesses a great deal of study of the role of the adrenergic nervous system upon the regulation of intraocular pressure. From the investigations it is possible to formulate an integrated concept that can place years of work and speculation on a firm molecular foundation. The secretory tissue of the eye, the ciliary processes, contain an enzyme receptor complex, comprised by receptor complex, comprised by receptor bound membrane proteins, the catalytic moiety of the enzyme, a guanyl nucleotide regulatory protein (or N protein) and other features. The enzyme can be activated by well known neurohumoral or humoral agents that consist of catecholamines, glycoprotein hormones produced by the hypothalamic pituitary axis, and other related compounds, including placental gonadotropin. These compounds cause the ciliary epithelia to produce cyclic AMP at an accelerated rate. Cyclic AMP, as a second messenger, causes, either directly or indirectly, a decrease in the rate of aqueous humor formation that may be modulated by cofactors. Clinical syndromes fit the experimental data so that an integrated explanation can be given for the reduced intraocular pressure witnessed under certain central nervous system and adrenergic influences. The molecular biology of this concept provides important leads for future investigations that bear directly both upon the regulation of intraocular pressure and upon glaucoma.
许多临床医生和研究科学家一直怀疑，眼内压可通过神经和/或体液对房水生成速率的影响来调节。将中枢神经系统对眼内压的特定影响与血管诱导的或其他继发性改变区分开来即便并非不可能，也是很困难的。在过去二十年里，对肾上腺素能神经系统在眼内压调节中的作用进行了大量研究。从这些研究中，可以形成一个综合概念，将多年的工作和推测建立在坚实的分子基础之上。眼睛的分泌组织睫状体包含一种酶受体复合物，它由受体结合膜蛋白、酶的催化部分、一种鸟苷酸调节蛋白（或N蛋白）及其他成分组成。该酶可被已知的神经体液或体液因子激活，这些因子包括儿茶酚胺、下丘脑 - 垂体轴产生的糖蛋白激素以及其他相关化合物，包括胎盘促性腺激素。这些化合物使睫状体上皮细胞加速产生环磷酸腺苷（cAMP）。环磷酸腺苷作为第二信使，直接或间接地导致房水生成速率降低，这可能会受到辅助因子的调节。临床综合征与实验数据相符，因此可以对在某些中枢神经系统和肾上腺素能影响下所观察到的眼内压降低给出一个综合解释。这一概念的分子生物学为未来直接涉及眼内压调节和青光眼的研究提供了重要线索。
