QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Susten, S. S. Articles by Kirksey, A. Search for Related Content PubMed PubMed Citation Articles by Susten, S. S. Articles by Kirksey, A.

Influence of Pyridoxine on Tyrosine Transaminase Activity in Maternal and Fetal Rat Liver¹

Foods and Nutrition Department, Purdue University, Purdue University, Lafayette, Indiana 47907

Massive doses of pyridoxine (100 mg/100 g body weight) were administered to nonpregnant and pregnant intact and adrenalectomized rats to determine whether alterations in tyrosine transaminase activity (TTA) and holotyrosine transaminase activity (HTA) could be produced and whether the responses differed in pregnant and nonpregnant states. Observations were made 5 hours after intraperitoneal injections of saline, cortisol or pyridoxine. Hepatic HTA tended to be higher and TTA was higher in saline-treated pregnant than in nonpregnant animals. Similar enzyme responses were observed in cortisol-treated animals compared with saline treated controls. Pyridoxine administration caused apparent stimulation of TTA and HTA in intact animals, but no increases in the enzyme activities were observed in similarly treated adrenalectomized rats. Similarities between the enzyme responses observed following pyridoxine administration and those following tyrosine administration are discussed in relation to age dependency. Increased TTA and HTA were observed only in fetuses from rats treated with pyridoxine, suggesting that the mechanism of stimulation of the enzyme by pyridoxine may be operative in fetal liver.

Manuscript received 12 September 1969.