Metabolism subcellular distribution

Livingstone DR, SV Farrar (1984) Tissue and subcellular distribution of enzyme activities of mixed-function oxygenase and benzo[a]pyrene metabolism in the common mussel Mytilis edulis L. Sci Tot Environ 39 209-235. 

Nemeroff CB, Krishnan KRR, Reed D, et al Adrenal gland enlargement in major depression a computed tomographic study. Arch Gen Psychiatry 49 384-387, 1992 Nestler EJ, Terwilliger RZ, Duman RS Chronic antidepressant administration alters the subcellular distribution of cyclic AMP-dependent protein kinase in rat frontal cortex. J Neurochem 53 1644-1647, 1989 Nestor PC, Parasuraman R, Haxby JV, et al Divided attention and metabolic brain dysfunction in mild dementia of the Alzheimer s type. Neuropsychologia 29(5) 379-387, 1991... 

Amine oxidation. As well as the microsomal enzymes involved in the oxidation of amines, there are a number of other amine oxidase enzymes, which have a different subcellular distribution. The most important are the monoamine oxidases and the diamine oxidases. The monoamine oxidases are located in the mitochondria within the cell and are found in the liver and also other organs such as the heart and central nervous system and in vascular tissue. They are a group of flavoprotein enzymes with overlapping substrate specificities. Although primarily of importance in the metabolism of endogenous compounds such as 5-hydroxy try pt-amine, they may be involved in the metabolism of foreign compounds. 

Daugherty JP, Clapp NK. 1976. Studies on nitrosamine metabolism I. Subcellular distribution of radioactivity in tumor-susceptible tissues of RFM mice following administration of (14C)dimethylnitrosamine. Life Sciences 19 265-271. 

Livingstone, D.R. and S.V. Farrar. 1984. Tissue and subcellular distribution of enzyme activities of mixed-function oxygenase and benzo[fl]pyrene metabolism in the common mussel Mytilis edulis L. Sci. Total Environ. 39 209-235 Lockhart, R., Wagemann, B. Tracey, D. Sutherland, and D.J. Thomas. 1992. Presence and implications of chemical contaminants in the freshwaters of the Canadian Arctic. Sci. Total Environ. 122 165-243. 

RNA molecules regulate their own metabolism. A number of structural features of RNA are known to influence stability, various processing events, subcellular distribution, and transport. It is likely that, as RNA intermediary metabolism is better understood, many other regulatory features and mechanisms will be identified. 

Matias et al. (2001) detected immunostaining in neural tissue of the leeches H. medicinalis and T. tessulatum using antibodies directed against the FAAH catalytic core (GGSSGGEGALI). The leech enzyme metabolized AEA, but it differed from mammalian FAAH in pH-dependency (optimal activity at pH 7 instead of pH 9 to 10), subcellular distributions (primarily cytosohc fractions instead of... 

Adair, W.L. Keller, R.K. (1982) Dolichol Metabolism in Rat Liver. Determination of the Subcellular Distribution of Dolichyl Phosphate and its Site and Rate of de novo Biosynthesis , Journal of Biological Chemistry, 257, 8990-6... 

Sarhan S. and Seiler N (1979) Metabolic inhibitions and subcellular distribution of GABA / Neurosci Res 4, 399-421... 

Paigen (1970) further proposed that a number of other inborn metabolic deficiencies may represent defects in architectural genes which regulate the subcellular distribution of specific acid hydrolases. Among these diseases would be included certain mucopolysaccharidoses characterized by a loss of one component of galactosidase (Ho and O Brien, 1969) and metachromatic leukodystrophy in which arylsulfatase A is missing (Austin, et at, 1963, 1965 Mehl and Jatzkewitz, 1965, 1968). 

Zinser, E., Paltauf, F. and Daum, G. (1993) Sterol composition of yeast organelle membranes and subcellular distribution of enzymes involved in sterol metabolism. J. Bacteriol. 175, 2853-2858. 

Taken together, nowadays we are able to study iron metabolism and distribution at the tissue, cellular, subcellular, or even molecular level by NATs independently or by combining NATs with a variety of pre-separation procedures. The improvement and upgrade of the qualitative and quantitative analytical techniques are the challenges for further progress on the species study at molecular level and the promotion for the development of metallo-genomics, metalloproteomics, and metallomics of iron. 

The rate of uptake from blood and by different organs varies widely, and so does the rate of elimination from different organs. Inorganic mercury is characterized by a markedly non-uniform distribution in the body. Compartmentali-zation of mercury within different parts of the organ or in subcellular structures, the binding of mercury to various chemical compounds within the cell, and the metabolic transformation of mercury, complicate the evaluation of distribution. 

The above definition of toxicity is concerned with living animals, i.e. in vivo studies. Toxicity can also be measured in vitro using mammalian cell or bacterial cultures or subcellular fractions (e.g. for mechanistic studies). However, such toxicity estimates made in vitro may not always reflect accurately the toxicity of a chemical to mammals since absorption, distribution, metabolism and excretion in vivo can markedly alter the profile of toxicity (82UP10502) (see also Section 1.05.2.6). 

Early determination of PK properties (absorption, distribution, metabolism, excretion and toxicity, ADMET) has become a fundamental resource of medicinal chemistry in the LO phase. New technologies have been developed to perform a great number of in vitro and even in silico tests. Currently, the most common early-ADME assays evaluate both physicochemical properties (such as the solubility in an opportune medium, the lipophilicity, and the p K i) and biophysical properties (such as the permeability through cellular monolayers to predict oral absorption and the metabolic stability after treatment with liver or microsomal subcellular fraction that contains oxidative cytochromes). 

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