Effects of PhXA41, a prostaglandin analogue, and PGF_2αon the corneal and intraretinal d.c. electroretinogram (ERG) of the albino rabbit eye

Abstract

PhXA41, a prostaglandin F2 alpha analogue, is a new drug alternative for medical treatment of glaucoma. From earlier studies, it is known that certain prostaglandins (pgs) exert an influence on the d.c. electroretinogram (ERG). In the present study, possible effects of intraocular perfusion with PhXA41 (free acid) or PGF2 alpha on the rabbit retina and retinal pigment epithelium (RPE) were evaluated. Unilateral vitrectomy was performed and a continuous intraocular perfusion was established, in which a reference solution was alternated with the test solution. In part one of the experiments, the corneal d.c. ERG and the standing potential of the eye (SP) were recorded from both eyes. In part two, vitreal and intraretinal d.c. ERG were recorded in the vitrectomized eye. PhXA41 and PGF2 alpha produced similar effects, i.e. a significant and reversible c-wave increase at concentrations of 1-10 micrograms/ml. No influence was found in the concentration interval 10-100 ng/ml. There were no changes in a- and b-wave amplitudes at any of the concentrations tested. At a concentration of 10 micrograms/ml, the SP increased significantly. The intraretinal d.c. ERG showed a large reduction of slow PIII accompanied by a small change in transepithelial potential (TEP). Theoretically, a vitreous concentration of less than 1 ng/ml may be reached after topical application. This concentration level does not influence the d.c. ERG in this animal model. At higher concentrations, a significant and reversible c-wave increase seemed to be generated mainly in the inner retina by a reduction of slow PIII generated in the Müller cells. The effect of PhXA41 appears to be mediated by an FP receptor.

Effects of Pituitary Adenylate-Cyclase-Activating Polypeptide on the Direct-Current Electroretinogram of the Rabbit Eye

“…However, the ERG amplitude levels are influenced by the surgical preparation and/or the irrigation. During control conditions, the b-and c-wave amplitude levels were significantly reduced compared to the contralateral eye, results which are in accordance with previous reports from our laboratory [5,10,11]. The a-wave amplitude was not affected, as in some of the earlier studies using similar techniques [5,8].…”

From basic to clinical research: a journey with the retina, the retinal pigment epithelium, the cornea, age‐related macular degeneration and hereditary degenerations, as seen in the rear view mirror

“…1974), solvents (Skoog & Nilsson 1981), dopamine (Textorius et al. 1989), prostaglandins (Jarkman & Skoog 1985; Bragadóttir & Jarkman 1995), and several other substances. Furthermore, a new system for perfusion of the rabbit vitreous cavity in combination with microelectrode direct current (DC) recordings had to be developed (Jarkman 1988).…”