-
La Clinica Terapeutica Mar 1974
Topics: Anesthetics; Animals; Anti-Inflammatory Agents; Anticonvulsants; Enzyme Induction; Hypnotics and Sedatives; Hypoglycemic Agents; In Vitro Techniques; Kidney; Lipid Metabolism; Lipoproteins; Lung; Microsomes; Microsomes, Liver; Pesticides; Pharmaceutical Preparations; Proteins; Rats; Skin; Steroids; Tranquilizing Agents
PubMed: 4846657
DOI: No ID Found -
Biological & Pharmaceutical Bulletin Mar 1997(RS)-[3-3H]-2,3-Oxidosqualene (1) was converted into (20S)-dammarenediol (2) and not to (20R)-dammarenediol by a microsomal fraction prepared from the hairy root of...
(RS)-[3-3H]-2,3-Oxidosqualene (1) was converted into (20S)-dammarenediol (2) and not to (20R)-dammarenediol by a microsomal fraction prepared from the hairy root of Panax ginseng. The enzyme activity was highest at pH 6.0 and was not increased by the addition of any detergents. These properties differed significantly from those of other 2,3-oxidosqualene cyclases reported from higher plants and animals.
Topics: Cyclization; Detergents; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; Microsomes; Panax; Plants, Medicinal; Squalene
PubMed: 9084891
DOI: 10.1248/bpb.20.292 -
Biochemical and Biophysical Research... Feb 19891- Anti-liver/kidney microsome autoantibodies type 1 (anti-LKM1), observed in some children with chronic active hepatitis, were used to isolate their antigen in human...
1- Anti-liver/kidney microsome autoantibodies type 1 (anti-LKM1), observed in some children with chronic active hepatitis, were used to isolate their antigen in human liver microsomes. A protein, called P-LKM1 was thus purified. This protein was recognized by a rabbit antiserum directed against the related human cytochromes P-450 bufI and P-450 bufII. 2- A human liver microsomal protein immunoprecipitated with anti-LKM1 sera was also recognized by anti cytochromes P-450 bufI/II antibodies. 3- Anti-LKM1 antibodies potently inhibited microsomal bufuralol 1'-hydroxylation. These results displayed the possible identity between cytochrome P-450 bufI/II and LKM1 antigen.
Topics: Autoantibodies; Autoantigens; Autoimmune Diseases; Cytochrome P-450 Enzyme System; Epitopes; Fluorescent Antibody Technique; Hepatitis, Chronic; Humans; Immunoblotting; Immunosorbent Techniques; Isoenzymes; Kidney; Microsomes; Microsomes, Liver
PubMed: 2466461
DOI: 10.1016/0006-291x(89)92435-2 -
Journal of Cancer Research and Clinical... 1991Five experimental anti-leukemic agents, 1-(2-chloroethyl)-4-arylacyl-1-nitrososemicarbazides, were synthesized and tested for genotoxicity in the Salmonella/mammalian...
Five experimental anti-leukemic agents, 1-(2-chloroethyl)-4-arylacyl-1-nitrososemicarbazides, were synthesized and tested for genotoxicity in the Salmonella/mammalian microsome assay. No strong mutagenic activity could be detected when tested with the S. typhimurium TA98. A clear dose-dependent base-pair-substitution mutagenic activity was observed with each compound when the tester strain TA100 was used with or without metabolic activation. The genotoxicity of the unsubstituted substance was similar to that of the known mutagenic cytostatic drugs, lomustin and carmustin, and was stronger than the mutagenicity of each substituted derivative.
Topics: Antineoplastic Agents; Microsomes; Mutagenicity Tests; Mutagens; Nitroso Compounds; Salmonella; Semicarbazides; Structure-Activity Relationship; Urea
PubMed: 1997463
DOI: 10.1007/BF01613187 -
Biochimica Et Biophysica Acta Oct 1969
Topics: Acyltransferases; Animals; Aorta; Cell Membrane; Cholesterol; Diet, Atherogenic; Glucose-6-Phosphatase; Haplorhini; Hypercholesterolemia; Lipids; Liver; Male; Methods; Microsomes; Microsomes, Liver; Nucleotidases; Phosphatidylcholines; Phosphatidylethanolamines; Phospholipids; Polysaccharides; Rats; Sphingomyelins
PubMed: 4310718
DOI: 10.1016/0005-2760(69)90017-4 -
Ukrains'kyi Biokhimichnyi Zhurnal 1975Mg2+-dependent Ca2+-activated ATPase (Mg2+, Ca2+-ATP-ase) of microsome fraction from grey matter of great cerebral hemispheres of cattle is activated by 0.1% solution of...
Mg2+-dependent Ca2+-activated ATPase (Mg2+, Ca2+-ATP-ase) of microsome fraction from grey matter of great cerebral hemispheres of cattle is activated by 0.1% solution of digitonin. Simultaneously 30-60% of initial fraction protein is extracted, respectively, with 0.1-0.3% concentrations of digitonin. The Mg2+- and Mg2+, Ca2+-ATPase activities manifest in solubilized protein. The maximal solubilization of both enzymes is reached when treating the fraction of brain microsomes with 0.3% solution of digitonin, the Mg2+, Ca2+-ATPase activity is not manifested in the 0.2% digitonin extract of this fraction. The Mg2+, Ca2+-ATPase activity is not always manifested in the 0.4% digitonin extract of the sediment which was obtained after extracting the initial fraction with 0.2% solution of digitonin. Addition of 0.2% extract to it causes manifestation or increase of the Mg2+, Ca2+-ATPase activity. Thus, minimum two components which are extracted by detergent in different concentrations or one of the extracted components which is an activator of solubilized Mg2+, Ca2+-ATPase may be necessary for manifestation of this activity in the solubilized components of the fraction of brain microsomes. The membrane components extracted with digitonin possess evidently a small molecular weight as they compose 7.5% polyacrylamide gel in which 0.4% digitonin extract of the brain microsome fraction is divided into 7-8 electrophoretic zones.
Topics: Adenosine Triphosphatases; Animals; Brain; Calcium; Cattle; Digitonin; Enzyme Activation; Magnesium; Microsomes; Solubility
PubMed: 128176
DOI: No ID Found -
Biochemical Pharmacology Oct 1991Response of rat kidney to the challenges by perfluorooctanoic acid (PFOA) was studied using microsomal 1-acyglycerophosphocholine (1-acyl-GPC) acyltransferase as a...
Response of rat kidney to the challenges by perfluorooctanoic acid (PFOA) was studied using microsomal 1-acyglycerophosphocholine (1-acyl-GPC) acyltransferase as a parameter. Marked induction of the enzyme was brought about in kidney of male rats, whereas the induction in kidney of female rats was far less pronounced. The sex-related difference in the response of kidney to PFOA was much more marked than those seen with p-chlorophenoxyisobutyric acid (clofibric acid) or 2,2'-(decamethy-lenedithio)diethanol (tiadenol). Hormonal manipulations revealed that the sex-related difference in the response of kidney to PFOA was strongly dependent on the state of gonadal hormones of rats. Even after a prolonged administration of PFOA for up to 26 weeks, this sex-related difference was still evident. Induction of peroxisomal beta-oxidation was brought about concurrently with microsomal 1-acyl-GPC acyltransferase and a high correlation was confirmed between the inductions of these two parameters.
Topics: 1-Acylglycerophosphocholine O-Acyltransferase; Acyltransferases; Animals; Caprylates; Enzyme Induction; Female; Fluorocarbons; Kidney; Male; Microsomes; Rats; Sex Factors
PubMed: 1741769
DOI: 10.1016/0006-2952(91)90590-2 -
The Journal of Biophysical and... Nov 1956The pancreatic exocrine cell of the guinea pig has a voluminous endoplasmic reticulum distinguished by extensive association with small, dense particles, and by its...
The pancreatic exocrine cell of the guinea pig has a voluminous endoplasmic reticulum distinguished by extensive association with small, dense particles, and by its orderly disposition in the basal region of the cell. In addition to the small, ( approximately 15 mmicro), dense particles attached to the limiting membrane of the endoplasmic reticulum, numerous particles of similar appearance are found freely scattered in the cytoplasmic matrix. The various cell structures of pancreatic exocrine cells can be satisfactorily identified in pancreatic homogenates. The microsome fraction consists primarily of spherical vesicles (80 to 300 mmicro), limited by a thin membrane (7 mmicro) which bears small ( approximately 15 mmicro) dense particles attached on its outer surface. The content of the microsomal vesicles is usually of high density. Pancreatic microsomes derive by extensive fragmentation mainly from the rough surfaced parts of the endoplasmic reticula of exocrine cells. A few damaged mitochondria and certain dense granules ( approximately 150 mmicro) originating probably from islet cells, contaminate the microsome fraction. Pancreatic microsomes contain RNA, protein, and a relatively small amount of phospholipide and hemochromogen. They do not have DPNH-cytochrome c reductase activity. In six experiments the RNA/protein N ratios were found grouped around two different means, namely 0.6 and 1.3. Pancreatic microsomes are more labile than liver microsomes but react in a similar way to RN-ase-(loss of the particulate component and RNA), and deoxycholate treatment (loss of the membranous component and of phospholipide, hemochromogen, and most of the protein). Postmicrosomal fractions consisting primarly of small ( approximately 15 mmicro), dense particles of ribonucleoprotein (RNA/protein N ratio = 1 to 2) were obtained by further centrifugation of the microsomal supernatant. The small nucleoprotein particles of these fractions are frequently found associated in chains or clusters.
Topics: Animals; Cytoplasm; Electrons; Endoplasmic Reticulum; Guinea Pigs; Histological Techniques; Microscopy; Microscopy, Electron; Microsomes; Microsomes, Liver; Pancreas; Phospholipids; Proteins; RNA
PubMed: 13398437
DOI: 10.1083/jcb.2.6.671 -
Journal of Pharmacy & Pharmaceutical... 2006To study the effect of protein and calorie malnutrition on in vitro drug metabolism of protein and calorie malnourished juvenile and adult rats.
PURPOSE
To study the effect of protein and calorie malnutrition on in vitro drug metabolism of protein and calorie malnourished juvenile and adult rats.
METHOD
Microsomal incubation was used as a means of monitoring drug metabolism changes, HPLC was employed to quantify metabolites and enzyme immunoassay (EIA) was used for rat growth hormone (rGH) monitoring.
RESULTS
Protein and calorie malnutrition significantly decreased levels of microsomal protein and total P450. Microsome of protein and calorie malnourished rats showed impaired testosterone 16alpha- and 2alpha- hydroxylation (CYP2C11), testosterone 6beta-hydroxylation (CYP3A), and testosterone 7alpha-hydroxylation (CYP2A1). Testosterone 16beta-hydroxylation (CYP2B1) did not show any significant change, neither in capacity nor affinity. The quantity and the secretion pattern of rGH were not altered in protein and calorie malnourished rats compared to those in healthy animals.
CONCLUSIONS
Serum albumin is not a good indicator of malnutrition. The capacity and affinity of CYP2C11, CYP3A and CYP2A1 were compromised by protein and calorie malnutrition. The impairment of drug metabolism in protein and calorie malnourished rats was not caused by the alteration of rGH.
Topics: Animals; Cytochrome P-450 Enzyme System; Male; Microsomes, Liver; Pharmaceutical Preparations; Protein-Energy Malnutrition; Rats; Rats, Sprague-Dawley
PubMed: 16849009
DOI: No ID Found -
Radiatsionnaia Biologiia, Radioecologiia 2003The action of 12-O-tetradecanoyl-13-acetate (TPA) in vitro in a wide range of concentration from 10(-3) mol/l down to ultra-low doses 10(-23) mol/l and dilution 10(-24)...
The action of 12-O-tetradecanoyl-13-acetate (TPA) in vitro in a wide range of concentration from 10(-3) mol/l down to ultra-low doses 10(-23) mol/l and dilution 10(-24) mol/l on the microsome membranes isolated from tumor--Ehrlich ascite carcinoma (EAC) has been studied by ESR-method using two spin probes: 5- and 16-doxyl stearates (5- and 16-DS) localized in the different regions of lipid bilayer. From the ESR spectra obtained it was calculated the following parameters: an order of the long axis 5-DS (S) related to order of the fatty acids chains in the lipid bilayer; two rotation correlation times (Tc1 and Tc2) of 16-DC to estimate a microviscosity value and structural-sensitive ones. It was found the stage changes of all these parameters (increase and decrease) as compared with control level (the membranes untreated by TPA) depending on TPA concentration into the range of 10(-3)-10(-24) mol/l; in particular, the most significant shape changes of structural-sensitive parameters have been observed at TPA doses below 10(-16) mol/l. It is concluded that tumor membranes are very sensitive to TPA action in vitro in a wide range of concentration included ultra-low doses.
Topics: Animals; Carcinoma, Ehrlich Tumor; Cell Membrane; Cyclic N-Oxides; Dose-Response Relationship, Drug; Electron Spin Resonance Spectroscopy; Lipid Metabolism; Lipids; Mice; Mice, Inbred Strains; Microsomes; Spin Labels; Tetradecanoylphorbol Acetate; Tumor Cells, Cultured
PubMed: 12881983
DOI: No ID Found