The Effect of Vitamin Supplementation on the Urinary Excretion of Tryptophan Metabolites by Pregnant Women*

Herpes Gestationis

“…This is interpreted as a sign of vitam in B6 deficiency. The pattern of ex cretion of tryptophane m etabolites in pregnancy is different in several respects from the pattern observed in B6 deficiency induced by desoxypyridine (no change or a decrease in the excretion of kynurenic acid, increased excretion of the pyridone metabolite of niacin), but these differences are probably a result of the endocrine changes as sociated with pregnancy [3]. The significance of this vitam in defi ciency, which may be compensated for by a daily supplem ent of 10 mg pyridoxine [2], has not been elucidated.…”

Association of Fetal Growth with Maternal Nutrition

“…Blood levels of B6 fall progressively during pregnancy to about !f4 of nonpregnancy levels (Coursin and Brown, 1961), while xanthenuric acid excretion increases 10-15 times (Wachstein and Graffeo, 1952). Supplementation with pyridoxine normalizes both parameters (Cleary et al, 1975;Brown et al, 1961). Pitkin (1975b) suggests that these biochemie al changes in pregnant women reflect physiologie adjustments of so me kind, rather than vitamin B6 deficiency.…”

Effect of treatment on the metabolism of tryptophan in childhood epilepsy.

“…In pregnancy, increased excretion of xanthurenic acid (Vandelli, 1951;Sprince, Lowry, Folsome, and Behrman, 1951;Wachstein and Gudaitis, 1952) or of xanthurenic acid, kynurenine, 3-hydroxykynurenine, and acetyl-kynurenine contrasts with the associated decreased excretion of kynurenic acid and an increase in nicotinamide and its metabolites (Brown, Thornton, and Price, 1961;Wertz, Lojkin, Bouchard, and Derby, 1958): the changes in diabetes (Wiseman, Kalant, and Hoffman, 1958) and scleroderma (Price, Brown, Rukavina, Mendelson, and Johnson, 1957) too are not readily explained in terms of pyridoxine deficiency.…”