-transparent.png){kind=logo}
The mechanism of the increase of phosphatidylcholine in liver, accompanying enzyme induction by phenobarbital, has been studied in rats. Using radioactively labeled precursors, the two main pathways of phosphatidylcholine biosynthesis--the CDP-choline pathway and the methylation of phosphatidylethanolamine--were analyzed after pretreatment with 4 doses of phenobarbital (80 mg/kg) on 3 consecutive days. After i.v. injection of choline [Me-3H], choline [Me-14C] or NaH2[32P]O4 the specific radioactivity (sp. act.) of phosphatidylcholine (dpm/nmol) was decreased by 60%, and after methionine [Me-3H] or ethanolamine [1.2-14C] by 40% compared to control rats. These changes are partly due to the increased concentration of phosphatidylcholine and phosphatidylethanolamine, causing the incorporated precursors to dilute, and partly to a secondary effect which leads to a reduction of the sp. act. of free choline in pretreated animals. The concentration of glycerylphosphorylcholine, one of the metabolites of phosphatidylcholine catabolism, was also diminished by almost 50%. From these results it may be concluded that the increase of phosphatidylcholine is due to a retardation of its breakdown rather than to an increase of its synthesis.
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
January 1976,
Biochimica et biophysica acta,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
January 1979,
General pharmacology,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
June 1987,
Xenobiotica; the fate of foreign compounds in biological systems,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
January 1983,
Archives of toxicology. Supplement. = Archiv fur Toxikologie. Supplement,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
January 1980,
The Journal of antimicrobial chemotherapy,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
March 1966,
Connecticut medicine,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
March 1974,
Comparative biochemistry and physiology. B, Comparative biochemistry,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
July 1974,
Research communications in chemical pathology and pharmacology,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
January 1981,
European surgical research. Europaische chirurgische Forschung. Recherches chirurgicales europeennes,
T H Schwartzkopff, and
G Schwartzkopff, and
O Pleul, and
H Kewitz
October 1981,
The Journal of biological chemistry,
