Prediction of renal tubular secretion of tetraethylammonium bromide by use of endogenous N1-methylnicotinamide in the rat.

The renal secretion of an endogenous N1-methylnicotinamide (NMN) and its use-fullness as an index of the renal secretion clearance of tetraethylammonium bromide (TEA), a representative organic cationic drug, was examined in the rats treated with folic acid, glycerol and uranyl nitrate, respectively. There was a statistically significant correlation between the renal secretion clearance of TEA and that of NMN in the intact and acute renal failure rats (r = 0.969, p less than 0.001). It was suggested that the renal secretion clearance of the endogenous NMN could be used as an index to assess the renal tubular function for the secretion of organic cationic drugs like TEA.