A vasorelaxing factor is released from mouse retinal tissue.
The present study aimed to demonstrate the release of a retinal relaxing factor (RRF) from the retina of mice and to investigate the identity of the RRF. Ring segments of a mouse aorta were mounted in a small vessel myograph. The relaxing influence of mouse retinal tissue was assessed by placing a retina in close proximity to the precontracted aorta. This elicited reliable and reproducible relaxations in the aorta. Both the nitric oxide (NO) synthase inhibitor N(omega)-nitro-L-arginine and the soluble guanylyl cyclase inhibitor 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one had no effect on the RRF response. Also the cyclooxygenase inhibitors indomethacin and sodium diclofenac failed to affect the retina-induced relaxations. Acute hypoxia largely enhanced retina-induced relaxations. It is concluded that mouse retinal tissue releases an RRF, that the mouse RRF response is not mediated by NO or prostanoids and that the mouse RRF response is profoundly influenced by hypoxia.
Boussery
Koen
K
Department of Physiology and Pathophysiology, Ghent University, De Pintelaan 185, Blok B, B-9000 Ghent, Belgium.
Franki
Ann Sophie
AS
Delaey
Christophe
C
Van de Voorde
Johan
J
D000208:Acute Disease; D000818:Animals; D001011:Aorta / Q000502:physiology / Q000503:physiopathology; D004008:Diclofenac / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors; D000860:Hypoxia / Q000503:physiopathology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D051379:Mice; D009131:Muscle, Smooth, Vascular / Q000503:physiopathology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000172:deficiency; D052248:Nitric Oxide Synthase Type I; D019335:Nitroarginine / Q000494:pharmacology; D010069:Oxadiazoles / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011810:Quinoxalines / Q000494:pharmacology; D012160:Retina / Q000378:metabolism* / Q000502:physiology; D012171:Retinal Vessels / Q000502:physiology*; D014661:Vasoconstriction; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*
C095284:1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one; D004791:Enzyme Inhibitors; D010069:Oxadiazoles; D011810:Quinoxalines; D004008:Diclofenac; D019335:Nitroarginine; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496321:Nos1 protein, mouse; D006162:Guanylate Cyclase; D011188:Potassium; D007213:Indomethacin