Purchase this article with an account.
David B. Bylund, David M. Chacko; Characterization of α2 Adrenergic Receptor Subtypes in Human Ocular Tissue Homogenates. Invest. Ophthalmol. Vis. Sci. 1999;40(10):2299-2306.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
purpose. To determine the predominant α2 adrenergic receptor
subtypes present in the human eye.
methods. Saturation- and competition-receptor–binding experiments were
performed with the radioligand [3H]RX821002 in human
ciliary body, retinal pigmented epithelium–choriocapillaris, iris, and
neurosensory retina. The affinities of various adrenergic antagonists
in these ocular tissues were compared with their affinities for the
cloned α2A, α2B, and α2C adrenergic receptor subtypes.
results. The density of α2 adrenergic receptors was highest in the
iris (440 femtomoles/mg protein), lowest in the neurosensory retina (14
femtomoles/mg protein), and intermediate in the other two tissues
(approximately 90 fmol/mg protein). The drug affinities in all four
human ocular tissues were highly correlated (correlation coefficients
between 0.94 and 0.97) with the affinities for the humanα 2A adrenergic receptor subtype and poorly correlated
(correlation coefficients between 0.15 and 0.66) with theα 2B and α2C subtypes.
conclusions. In agreement with previous studies in several animal species, theα 2 adrenergic receptors in the human ciliary body,
retinal pigmented epithelium–choriocapillaris, iris, and neurosensory
retina are predominately of the α2A subtype.
This PDF is available to Subscribers Only