Specific receptor sites for PAF in iris and ciliary body of the rabbit eye.
The existence of specific binding sites by using tritiated 1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphocholine (3H-PAF) was investigated on iris and ciliary body tissue of pigmented rabbit eyes. The binding was saturable, specific, time-dependent and reversible. Scatchard's analysis indicated the presence of two types of binding sites with a Kd1 4.90 +/- 0.47 nM, a Kd2 11.60 +/- 0.33 nM, a Bmax1 3.17 +/- 0.50 pmol/mg protein and a Bmax2 12.45 +/- 2.30 pmol/mg protein for iris tissue, and a Kd1 5.71 +/- 0.09 nM, a K2d 24.40 +/- 0.91 nM, a Bmax1 3.41 +/- 1.00 pmol/mg protein and a Bmax2 16.60 +/- 0.51 pmol/mg protein for ciliary body. The binding was fully displaced by unlabelled PAF in both iris and ciliary body preparations, and partially inhibited by the PAF antagonist BN 52021 in iris tissue.
van Delft
J L
JL
Laboratory of the Department of Ophthalmology, University Hospital, Leiden, The Netherlands.
van Haeringen
N J
NJ
Verbeij
N L
NL
Domingo
M T
MT
Chabrier
P E
PE
Braquet
P
P
D000818:Animals; D002924:Ciliary Body; D004224:Diterpenes; D005260:Female; D046934:Ginkgolides; D066298:In Vitro Techniques; D007498:Iris; D007700:Kinetics; D007783:Lactones / Q000037:antagonists & inhibitors; D008297:Male; D015394:Molecular Structure; D010972:Platelet Activating Factor / Q000378:metabolism*; D010980:Platelet Membrane Glycoproteins; D011817:Rabbits; D011956:Receptors, Cell Surface / Q000032:analysis*; D043562:Receptors, G-Protein-Coupled
D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor; C045856:ginkgolide B