Purchase this article with an account.
F. Schroedl, A. Brehmer, W. L. Neuhuber, D. Nickla; Nitrergic Innervation of the Chicken Choroid: A Developmental Study. Invest. Ophthalmol. Vis. Sci. 2007;48(13):1228.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Nitrergic innervation in the chicken choroid mainly derives from intrinsic choroidal neurons (ICN) and from the pterygopalatine ganglion. Known targets are choroidal blood vessels and non-vascular smooth muscle cells, which might be involved in changes in choroidal thickness and blood flow. Experimental studies in the chicken eye are mainly conducted within two weeks after hatching. Since data about the nitrergic innervation of the choroid at this stage as well as embryological data are lacking, filling this gap was aim of the study.
Choroids of chick embryos (n=2, of different animals each) at embryonic day (E) 7, 9, 12, 14, 16, 18 and 20, as well as choroids at 1, 5, 7, 8, 9, 11, 13, 15, 30 and 45 days (D) after hatching (n= 4, of different animals each) were prepared for NADPH-diaphorase reaction. Nitrergic activity was documented and ICN were quantified.
Endothelial NADPH-d reaction product in choroidal blood vessels was detectable as early as E7, while perivascular nitrergic nerve fibers appeared as early as E18. Single ICN were detectable as early as E16. From this time point, their amount increased almost linear from only a few at hatch-day to several hundreds at D45.
At present, we can not exclude if NO-production shows a delayed up-regulation after hatching or if a post-hatch migration of ICN into the choroid exists. Both mechanisms, delayed NO-production and migration, might be guided by visual stimuli. Nevertheless, the increasing nitrergic activity after hatching has to be considered in experimental design.
This PDF is available to Subscribers Only