Endothelin receptors in the detached retina of the pig

Endothelin-1 (ET-1) is a potent vasoconstrictor that causes hypoperfusion of the neurosensory retina. We investigated immunohistochemically the expression of the receptors for ET-1, ET(A) and ET(B), in control and locally detached retinas of the pig. Immunoreactivity for ET(A) was expressed in the innermost retinal layers and in the outer plexiform layer in control retinas, and was additionally strongly expressed by retinal blood vessels at 7 days after detachment of the sensory retina from the pigment epithelium. Immunoreactivity for ET(B) was expressed by the innermost retinal layers, by ganglion cell somata, and by Müller glial cells in the control tissue, and was not altered in its expression after detachment. The vascular expression of ET(A) may suggest a hypoperfusion of the retina after detachment.