Subcellular localization of gamma-glutamyltransferase activity in guinea pig liver. Effect of phenobarbital on the enzyme activity levels

Clinica Chimica Acta; International Journal of Clinical Chemistry
N E Huseby


The localization of gamma-glutamyltransferase activity in guinea pig liver was studied after subcellular fractionation. The enzyme activity was essentially connected with plasma membranes whereas only low activity was found in the endoplasmic reticulum. A similar activity distribution was demonstrated for 5'-nucleotidase. Highest specific activity of gamma-glutamyltransferase was found in plasma membranes enriched in bile canaliculi. In this fraction the specific activity was 35 times greater than the specific activity of the total homogenate, a value similar to the relative specific activity of (Na+,K+)-ATPase. More than 90% of the total gamma-glutamyltransferase activity in guinea pig liver was connected with parenchymal cells and the enzyme seemed to have an outside orientation. Animals treated with phenobarbital showed moderate increased in gamma-glutamyltransferase activity in serum and liver, whereas high activities were found in most bile samples. No particular liver subfraction showed substantial accumulation of gamma-glutamyltransferase activity. The present findings do not support the suggested use of serum gamma-glutamyltransferase measurements as a direct index of "microsomal enzyme induction".


Mar 15, 1983·Klinische Wochenschrift·M Nishimura, R Teschke
Jan 1, 1985·Comparative Biochemistry and Physiology. B, Comparative Biochemistry·S J Sulakhe, W W Lautt
Jul 1, 1991·The British Journal of Dermatology·R W GrovesD M MacDonald
Jul 1, 1981·Pathology, Research and Practice·C BusachiV Desmet
Jun 1, 1980·Pharmacological Research Communications·D BagrelG Siest
Mar 16, 1981·Biochemical and Biophysical Research Communications·M NishimuraR Teschke
Nov 1, 1991·Hepatology : Official Journal of the American Association for the Study of Liver Diseases·A J Lança, Y Israel
May 1, 1990·Hepatology : Official Journal of the American Association for the Study of Liver Diseases·H SpeiskyY Israel
Jan 1, 1986·Alcoholism, Clinical and Experimental Research·H IshiiM Tsuchiya
Oct 1, 1984·Journal of Applied Toxicology : JAT·M García, M Mourelle
Jan 1, 1980·CRC Critical Reviews in Clinical Laboratory Sciences·D M Goldberg


Jul 3, 1978·European Journal of Biochemistry·S HoriuchiY Morino
Aug 14, 1971·Lancet·G A MoroniS Del Prete
Oct 9, 1971·Lancet·L K Csatary
Jul 1, 1971·The Journal of Cell Biology·C de Duve

Related Concepts

Establishment and Maintenance of Localization
Adenosine Triphosphatases
Gamma-glutamyl transferase
Gamma Glutamyl Transferase Measurement
Cell Nucleus
Gamma-glutamyltransferase Activity
Subcellular Fractionation
Microsomes, Liver

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