N-Methyl-D-Aspartic Acid Receptor-Mediated Vasodilation Is Attenuated in the Retinas of Diabetic Rats.
Curr Eye Res
; 47(8): 1193-1199, 2022 08.
Article
em En
| MEDLINE
| ID: mdl-35485610
ABSTRACT
PURPOSE:
Activation of N-methyl-d-aspartic acid (NMDA) receptors enhances nitric oxide (NO) production in retinal neuronal cells, and in turn, NO released from neuronal cells induces glial cell-mediated dilation of retinal arterioles in rats. The purpose of this study was to examine how neuronal cell-dependent, glial cell-mediated vasodilation is impacted in diabetic rat retinas.METHODS:
Diabetes was induced in 6-week-old male Wistar rats by combining streptozotocin injection and D-glucose feeding. Two weeks later, the dilator function of retinal arterioles was assessed.RESULTS:
Compared with non-diabetic rats, the dilator responses of retinal arterioles induced by intravitreal injection of NMDA and NOR3, an NO donor, were reduced in diabetic rats. Following the blockade of large-conductance Ca2+-activated K+ (BKCa) channels with iberiotoxin, no significant difference in the retinal vasodilator response to NOR3 was observed between non-diabetic and diabetic rats. Intravitreal injection of 14,15-epoxyeicosatrienoic acid, a vasodilatory factor released from glial cells, dilated retinal arterioles, and the response was diminished by diabetes.CONCLUSION:
These findings suggest that the impaired BKCa channel function in vascular cells is responsible for the diminished neuronal cell-dependent, glial cell-mediated dilation of retinal arterioles during the early stage of diabetes.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vasodilatação
/
Diabetes Mellitus
Limite:
Animals
Idioma:
En
Revista:
Curr Eye Res
Ano de publicação:
2022
Tipo de documento:
Article