Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study proposes a technique, using Metrizamide, which permits the preparation of brown adipose tissue plasma membranes from the crude mitochondria as well as from the crude microsome fraction. These plasma membranes have high relative specific activities of their marker enzyme, 5'-nucleotidase (15 +/- 3 and 14 +/- 2 respectively) and, particularly those originating in the crude microsomes, are relatively free of mitochondria contamination. This study also shows the influence of the mode of cell disruption on microsome integrity. When cell disruption was achieved by grinding in liquid nitrogen the purified microsome NADPH cytochrome c reductase specific activity was found to be 3.5 times greater than that of microsomes obtained after homogenization of the tissue.
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PMID:Subcellular fractionation of brown adipose tissue. 54 24

Rat hepatocytes were isolated by a collagenase perfusion technique with subsequent subfractionation on Metrizamide gradients into subpopulations which have been designated band I and band II and are likely to be enriched with centrilobular and periportal cells, respectively. Band I was found to have a higher concentration of 5'-nucleotidase and band II a higher concentration of alcohol dehydrogenase. Furthermore, pretreatment of rats with phenobarbital led to higher cytochrome P-450 in the band I (centrilobular enriched) as compared to the band II (periportal enriched) subpopulations of hepatocytes. These data support their ascribed lobular origins. The uptake of a single concentration of galactose, ouabain and taurocholate into each of the two subpopulations was investigated until the concentration within the hepatocytes no longer increased. No difference was found in the uptake of [14C]galactose (25 mM) between the two hepatocyte subpopulations. However, the uptake of [3H]ouabain (125 microM) was greater in the centrilobular as compared to periportal enriched fraction of the hepatocytes. An even greater difference was found for the uptake of [3H]taurocholate (25 microM). The kinetics of taurocholate uptake were subsequently investigated. The Km for each subpopulation was 21 microM, while the Vmax of the centrilobular enriched fraction was 2.03 and that of the periportal enriched fraction was 1.57 nmol/min/mg of protein. These results show that there is a difference in uptake into hepatocytes of centrilobular and periportal origin for ouabain and taurocholate, but not for galactose.
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PMID:Uptake of galactose, ouabain and taurocholate into centrilobular and periportal enriched hepatocyte subpopulations. 720 41