Regulative action of cyclic AMP and histamine on the immune response mediated by surface receptors of cells.

The study of the effect of histamine and cAMP on the proliferation of lymphocyte populations has shown that both substances induce a significant decrease in the rate of T-suppressor proliferation. This effect can be neutralized by methiamide--a blocker of H2-histamine receptors. The obtained results point out the possibility of a regulative effect of cAMP on the proliferation of T-suppressors. This effect is mediated by surface receptors of the cell which are similar to or identical with H2-histamine receptors.

[Comparative study of the toxic, anaphylactoid, and sensitizing properties of 5-sulfo-8-mercaptoquinolinates of metals of the 8th and 3d groups of the periodic table]. / Sravnitel'noe issledovanie toksicheskikh, anafilaktoidnykh i sensibiliziruiushchikh svoistv 5-sul 'fo-8-merkap tokhinolinatov metallov VIII i III grupp periodicheskoi tablitsy.

Pronounced allergizing action of the compounds of group VIII metals of the periodic system, observed in occupational pathology and commencement of their wide clinical application as cancerostatic agents require a comprehensive study of the properties of these substances. Anaphylactoid, toxic and genuine sensitizing action of 5-sulfo-8-mercapto-quinolinates of group YIII metals and those of group III metals having similar properties was studied and compared with reference to 8 compounds. It was shown that histamine liberation from mast cells induced by these substances as well as inhibition of the respiration of mast cells depend on the central atom and electronic structure of the ligand. The mechanism of histamine liberation observed was similar to that of specific antigen and was related to the preservation of the respiratory processes, the system of microtubules and cell cyclic nucleotides. The compounds tested were also capable of sensitizing the animal in intracutaneous injection of the substance without exogenous carrier. Sensitization developed according to the reaction of both the immediate and delayed types.

Histamine releasing and histamine binding action of platinum and palladium compounds.

Platinum and palladium salts were shown to possess either histamine releasing or histamine binding properties. Both these effects were dependent on chemical structures of the tested compounds and might be drawn up in the following sequences; Pd greater than Pt, PtIV greater than PtII, NO2 greater than F greater than Cl greater than SCN greater than J, trans greater than cis. One of the possible mechanisms of anti-tumoral effect of platinum and palladium salts might be their marked histamine binding activity.

[Allergenic and anaphylactoid properties of carcinostatic compounds of platinum]. / Allergennye i anafilaktoidnye svoistva kantserostaticheskikh soedinenii platiny.

Different effects of platinum salts on the organism were studied comparatively. The toxic effect was estimated by LD50; the carcinogenic one--by the action on Ehrlich ascites tumor; the anaphylactoid effect was evaluated by the degree of the arterial pressure fall, the development of bronchospasm and an increased blood histamine level in cats under intravenous injection of platinum salts. The sensitization action of platinum salts was assessed on guinea pigs. All these effects are found to be dependent on the salts chemical composition, and they are manifested in an independent route.