title: Differential sensitivity of T suppressor cell expression to inhibition by histamine type 2 receptor antagonists.
abstract: The ability of the histamine type 2 (H2) receptor antagonists cimetidine and oxmetidine to inhibit the immune suppression mediated by different types of murine T suppressor cells has been evaluated. Both compounds at doses as low as 1 mg/kg administered as a per os (p.o.) twice a day (b.i.d.) regimen abrogated the expression of dinitrobenzene sulfonic acid-induced, Lyt-2+, T suppressor cells and stimulated contact sensitivity to dinitrofluorobenzene in adoptive transfer experiments. Comparable inhibition of Lyt-1+, T suppressor cell activity induced by UV irradiation required higher doses of cimetidine and oxmetidine (200 and 25 mg/kg; p.o., b.i.d., respectively). In contrast, the T suppressor cell-mediated unresponsiveness induced by inoculation with a high dose of sheep red blood cells was refractory to treatment in vivo with either cimetidine or oxmetidine regardless of the dose. These results indicate that T suppressor cell populations differ markedly in their susceptibility to modulation by H2 antagonists. The histamine type 1 (H1) receptor antagonist diphenhydramine, had no effect on suppressor cell activity in any of these systems, indicating that modulation of suppressor cell activity is mediated through an H2 receptor interaction.
mesh_terms: D000818:Animals; D001557:Benzenesulfonates / Q000494:pharmacology; D002927:Cimetidine / Q000494:pharmacology; D003877:Dermatitis, Contact / Q000276:immunology; D004155:Diphenhydramine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006635:Histamine H2 Antagonists / Q000494:pharmacology*; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007093:Imidazoles / Q000494:pharmacology; D007111:Immunity, Cellular / Q000187:drug effects; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology* / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D001557:Benzenesulfonates; D006635:Histamine H2 Antagonists; D007093:Imidazoles; C007488:dinitrobenzenesulfonic acid; D002927:Cimetidine; D004155:Diphenhydramine; C027703:oxmetidine