The utilization of intravenously infused pyridoxine in humans.
The utilization of a usual dose of intravenously infused pyridoxine (100 mg pyridoxine hydrochloride) was investigated in ten healthy males. Blood plasma and erythrocytes were investigated by means of high-performance liquid chromatography. Detectable metabolites in blood plasma were pyridoxine, pyridoxal 5'-phosphate, pyridoxal and 4-pyridoxic acid. In erythrocytes pyridoxine, pyridoxal 5'-phosphate, pyridoxal, and pyridoxamine 5'-phosphate were found. From their concentration-time curves rate constants of elimination and invasion, volume of distribution (pyridoxine) and the areas under the curves were calculated. Values for concmax and tmax are reported. A comparison with earlier results of oral pyridoxine administration revealed a better utilization after intravenous than after oral application, i.e. a greater build-up of coenzyme forms. A regulatory phenomenon in erythrocytes caused by high doses of pyridoxine is described. In view of the potential toxicity of pyridoxine the doses used in parenteral nutrition are called into question.
Zempleni
J
J
Institute of Nutritional Science, Justus-Liebig-University, Giessen, Germany.
Kübler
W
W
D000328:Adult; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D011730:Pyridoxal / Q000097:blood; D011732:Pyridoxal Phosphate / Q000097:blood; D011733:Pyridoxamine / Q000031:analogs & derivatives / Q000097:blood; D011736:Pyridoxine / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism*
D011730:Pyridoxal; D011732:Pyridoxal Phosphate; D011733:Pyridoxamine; D011736:Pyridoxine; C010627:pyridoxamine phosphate