[Possible mechanisms of the antitoxic action of calcium-containing derivatives of pantothenic acid in streptomycin poisoning].

Calcium salts of pantothenate (CPN), 4'-phosphopantothenate (CPP), S-sulfopantetheine (CSP), as well as pantetheine and panthenol were administered to mice by various routes and the influence of the administration route on acute toxicity of streptomycin (500 mg/kg, subcutaneously) was studied. It was shown that with subcutaneous, intramuscular, intraperitoneal and intravenous administration of CPN, CPP and CSP the acute toxicity of streptomycin was lower. The value of ED50 and the ranges of the antitoxic action (LD50/ED50) were indicative of high efficacy of CPP on its intravenous administration. In rats all the tested compounds normalized the liver excreting function (bromsulphalein test) impaired by exposure to streptomycin in subtoxic doses (200 mg/kg). The lowest levels of acetylation of the sulfacyl sodium test dose were observed in the animals treated with streptomycin in combination with CPN, CPP or CSP which could be explained by increased excretion and acetylation (detoxication) of the antibiotic.