High prostaglandin-E 1 binding to serum protein in allergic subjects

Abstract

Protein binding to both salicylate and 3H-labelled prostaglandin-E 1, ([ 3H]PGE 1) was examined in the sera of 22 allergic and 16 normal individuals. Protein binding to salicylate (P < 0.001) and to [ 3H]PGE 1 (P < 0.01) was significantly greater in the allergic than in the normal group. The nature of the binding sites of salicylate and PGE 1 was investigated with two fluorescent probes, dansylamide and dansylsarcosine as specific marker ligands for established Sites I and II, found to be specific for anionic drugs. The serum protein of 11 allergic subjects showed a higher binding at Site I (P < 0.05) and a lower binding at Site II (P < 0.05) than that of seven normal subjects. Salicylate and [ 3H]PGE 1] bound competitively at the two sites. It was concluded, when comparing allergic to normal subjects, that the high protein binding of allergic individuals to salicylate and PGE 1: could be attributed to qualitative and/or quantitative differences in the lipophilic substances which are tightly bound to the albumin of normal sera, causing a reduction in binding ability at Site I.