Purchase this article with an account.
Teruyo Kida, Hidehiro Oku, Takatoshi Kobayashi, Tsunehiko Ikeda; High Glucose Inhibits Insulin-induced Nitric Oxide Production In Microvessels Of Rat Retina. Invest. Ophthalmol. Vis. Sci. 2011;52(14):3561.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate insulin-induced nitric oxide (NO) production in retinal microvessels.
Microvascular complexes were freshly isolated from retinas of healthy rats by a "tissue-print" method. The retinal microvessels were incubated in different concentration of glucose (5.5 mM and 20 mM) with or without addition of insulin. Changes of NO production in the retinal microvessels were semiquantitatively determined by the time-lapse recording of fluorescent intensity of DAF, a fluorescein probe, using a laser scanning confocal microscope (LSM 510 Meta, Carl Zeiss, Jena, Germany). In addition, cell viability of pericyte in each condition was assayed by trypan blue exclusion.
Exposure of microvessels to insulin in 5.5 mM glucose, the fluorescent intensity was significantly increased (P=0.0031, ANOVA, post hoc test, Scheffe), while the insulin-induced NO production was significantly suppressed when vessels were incubated in 20 mM glucose. Besides, insulin decreased cell viability of pericyte in media with 20 mM glucose, while insulin did not affect cell viability in media with 5.5 mM glucose.
Insulin increased production of NO and may contribute to the microcirculation of retina. However, this NO-mediated action of insulin is suppressed under high glucose condition. These results may account for impairment of retinal circulation under diabetic conditions.
This PDF is available to Subscribers Only