0000000000766187
AUTHOR
Marcin L. Kordasz
Functional Role of α1-Adrenoceptor Subtypes in Murine Ophthalmic Arteries
PURPOSE To identify the α(1)-adrenoceptor (α(1)-AR) subtypes mediating vascular adrenergic responses in murine ophthalmic arteries. METHODS Expression of mRNA was quantified for individual α(1)-AR subtypes in murine ophthalmic arteries using real-time PCR. To assess the functional relevance of α(1)-ARs for mediating vascular responses, ophthalmic arteries from mice deficient in one of the three α(1)-AR subtypes (α(1A)-AR(-/-), α(1B)-AR(-/-), and α(1D)-AR(-/-), respectively) and wild-type controls were isolated, cannulated with micropipettes, and pressurized. Changes in luminal artery diameter in response to the α(1)-AR agonist phenylephrine, the sympathetic transmitter noradrenaline, and to…
Role of 1-Adrenoceptor Subtypes in Pupil Dilation Studied With Gene-Targeted Mice
PURPOSE The α₁A-adrenoceptor (α₁A-AR) subtype was suggested to mediate contraction and trophic effects in the iris dilator muscle, and thus its pharmacological blockade may be involved in intraoperative floppy iris syndrome. We tested the hypothesis that the α₁A-AR mediates pupil dilation and trophic effects in the mouse iris. METHODS The α₁-AR subtype mRNA expression was quantified in iris tissue by real-time PCR. To assess the role of individual α₁-ARs for mediating pupil dilation, the α₁-AR agonist phenylephrine was topically applied to the ocular surface of mice deficient in one of the three α₁-AR subtypes (α₁A-AR(-/-), α₁B-AR(-/-), α₁D-AR(-/-), respectively) and wild-type controls. Cha…
Role of nitric oxide synthase isoforms for ophthalmic artery reactivity in mice.
Abstract Nitric oxide synthases (NOS) are involved in regulation of ocular vascular tone and blood flow. While endothelial NOS (eNOS) has recently been shown to mediate endothelium-dependent vasodilation in mouse retinal arterioles, the contribution of individual NOS isoforms to vascular responses is unknown in the retrobulbar vasculature. Moreover, it is unknown whether the lack of a single NOS isoform affects neuron survival in the retina. Thus, the goal of the present study was to examine the hypothesis that the lack of individual nitric oxide synthase (NOS) isoforms affects the reactivity of mouse ophthalmic arteries and neuron density in the retinal ganglion cell (RGC) layer. Mice defi…