Wolfensberger T J, Holz F G, Ationu A, Carter N D, Bird A C
Department of Clinical Ophthalmology, Moorfields Eye Hospital, London, UK.
Ger J Ophthalmol. 1994 Aug;3(4-5):248-52.
Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) play a role in transepithelial fluid movement in the kidney and at the blood-aqueous barrier. We sought a similar natriuretic peptide-mediated regulatory system at the level of the blood-retinal barrier by investigating human neural retina and retinal pigment epithelium for the presence of ANP, BNP and their receptors. ANP and BNP binding to receptors could be demonstrated autoradiographically in all layers of the retina inclusive of the retinal pigment epithelium. Competitive preincubation with unlabeled peptides blocked the binding of the respective radioactive peptide. ANP and BNP could also be demonstrated immunohistochemically in both the neural retina and the retinal pigment epithelium. Our results suggest a role of these peptides both in the regulation of intraretinal fluid movement and--by analogy with other peptides--as possible neutrotransmittors. The localisation of ANP and BNP in the retinal pigment epithelium suggests that these peptides may influence ocular fluid homeostasis at the outer blood-retinal barrier by modulating pigment epithelial function.
心房利钠肽（ANP）和脑利钠肽（BNP）在肾脏的跨上皮液体转运以及血-房水屏障中发挥作用。我们通过研究人类神经视网膜和视网膜色素上皮中ANP、BNP及其受体的存在情况，探寻血-视网膜屏障水平上类似的利钠肽介导的调节系统。通过放射自显影法可在包括视网膜色素上皮在内的视网膜各层中证实ANP和BNP与受体的结合。与未标记肽进行竞争性预温育可阻断相应放射性肽的结合。免疫组织化学方法也可在神经视网膜和视网膜色素上皮中证实ANP和BNP的存在。我们的结果提示这些肽在视网膜内液体转运调节中发挥作用，并且——与其他肽类似——可能作为神经递质。ANP和BNP在视网膜色素上皮中的定位表明，这些肽可能通过调节色素上皮功能，在外部血-视网膜屏障处影响眼内液体稳态。
