American Journal of Clinical Nutrition, Vol 21, 715-722, Copyright © 1968 by The American Society for Clinical Nutrition, Inc.

Effects of Orally Administered N-Acetyl-l-Cysteine and N-Acetyl-dl-Penicillamine on Vitamin B₆ Availability and Copper Excretion in the Rat

¹ From the Department of Biochemistry, Mead Johnson Research Center, Evansville, Indiana

The effect of N-acetyl-l-cysteine and N-acetyl-dl-penicillamine upon vitamin B₆ availability was studied in rats. The sulfhydryl compounds were administered orally for 6 weeks and vitamin B₆ availability was evaluated from studies of weight gain, food efficiency, xanthurenic acid excietion after a tryptophan load, serum and liver transaminase levels, and vitamin B₆ excretion in the urine. In addition, the effect of these thiols on copper excretion in the urine was measured.

The results indicate that neither compound influenced the availability of vitamin B₆ in the rat at dose levels per kilogram body weight as high as 10 times that used clinically. N-Acetyl-l-cysteine and N-acetyl-dl-penicillamine were also ineffective as copper-chelation agents. The known antivitamin B₆ and copper-chelation properties of dl-penicillamine were demonstrated. The lack of effect of N-acetyl-dl-penicillamine on the parameters studied indicates that this compound is not deacetylated by the rat to penicillamine.