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PubMed1992

Endopeptidase 24-16 in murines: tissue distribution, cerebral regionalization, and ontogeny.

The tissue distribution, cerebral regionalization, and ontogeny of endopeptidase 24-16 were established in murines by means of its quenched fluorimetric substrate, Mcc-Pro-Leu-Gly-Pro-D-Lys-Dnp, and its selective dipeptide blocker, Pro-Ile. Endopeptidase 24-16 was particularly abundant in the liver and kidney, and the lowest specific activity was detected in the heart. In the brain, a 16-fold difference in specific activity was observed between the poorest and the richest cerebral areas. Endopeptidase 24-16 appeared in high concentrations in the olfactory bulb and tubercule, cingulate cortex, medial striatum, and globus pallidus, and was particularly weak in the CA1, CA2, and CA3 parts of the hippocampal formation and in the cerebellum. Endopeptidase 24-16 content in thirteen thalamic nuclei indicated a rather homogeneous distribution. This homogeneity was not observed in the hypothalamus, where pronounced variations occurred between enriched zones such as suprachiasmatic and arcuate nuclei and relatively poor areas such as periventricular and supraoptic nuclei. Endopeptidase 24-16 appeared to be developmentally regulated in the mouse brain; it was already detected at the fetal stage, increased transiently after birth, then regularly declined until adulthood.

Amino Acid Sequence↗

PubMed1991

Adipose tissue distribution changes during rapid weight loss in obese adults.

Changes in adipose tissue distribution as defined by the waist-to-hip ratio (WHR), were evaluated in 16 android, obese subjects (seven male and nine female) given a very low energy ketogenic diet of 1.72 MJ (411 kcal) for 4 weeks. Total weight loss was significantly greater for the males (11.2 +/- 2.5 kg) compared to females (8.3 +/- 0.8 kg); the relative weight loss however, was similar (9.9 vs 9.3 percent). Female and male losses in percent body fat and lean body mass were not significantly different. For both groups, significant (P less than 0.01) changes in waist and hip circumferences were observed; however, no significant changes were observed in WHR. These results indicate that in obese android male and female subjects, adipose tissue distribution as measured by WHR, does not change in response to rapid weight loss.

Adipose Tissue↗

PubMed1978

Cell and tissue distribution of 14C-labeled pyran copolymer.

The tissue distribution of pyran (maleic anhydride-divinyl ether) copolymer was studied after a single ip injection of 14C-labeled pyran (25 mg/kg) to mice. The pyran showed a reticuloendothelial distribution with the liver and spleen containing the highest concentrations which persisted for at least 21 days after drug treatment. Blood levels of 14C-pyran reached a peak 2 hours after injection and were cleared within 6 hours. Attempts to measure uptake of 14C-pyran by peritoneal macrophages were unsuccessful due to an inability to recover macrophages between 3 and 24 hours after ip pyran administration. Since activated macrophages appear to be the primary mechanism by which pyran enhances host resistance to microbial infection and neoplasia, the uptake of 14C-pyran by isolated peritoneal macrophages in vitro was studied. Purified macrophages showed a gradually increasing uptake of 14C-pyran, and a large amount of cell-associated radioactivity was bound to trichloroacetic acid-precipitable material. Several polyanions, including unlabeled pyran, dextran sulfate, and poly(I)-poly(C), competed for acid-precipitable receptor molecules. The superior antitumor effects of pyran as compared to other polyanions may result from the continuous presence of the synthetic polymer in the host. Possible mechanisms of immunopotentiation by pyran are discussed.

Animals↗

PubMed1986

Alcohol dehydrogenase isozymes in baboons: tissue distribution, catalytic properties, and variant phenotypes in liver, kidney, stomach, and testis.

Isoelectric focusing and cellulose acetate electrophoresis were used to examine the multiplicity, tissue distribution, and variability of alcohol dehydrogenase (ADH) among baboons, a primate species used as a model for research on alcohol metabolism and alcohol-induced liver pathology. Five major ADH isozymes were resolved and distinguished on the basis of their isoelectric points, tissue distributions, relative activities with alcohol substrates, and sensitivities to inhibition with 4-methyl pyrazole. ADH-1 and ADH-2 exhibited class I kinetic properties and were observed in high activity in kidney and liver extracts, respectively. ADH-3 showed class II kinetic properties, exhibiting high activity in stomach extracts, and was widely distributed in extracts of other baboon tissues, including kidney, esophagus, heart, testis, brain, and male sex accessory tissues. ADH-4 also showed class II ADH properties but was found only in liver (similar to human "pi-ADH"). ADH-5 exhibited class III ADH kinetic properties, being inactive with ethanol up to 0.5 M (similar to human "chi-ADH") and was distributed widely in baboon tissue extracts. Major activity variation was observed for liver ADH-4 between different animals. An electrophoretic variant for ADH-3 was observed for the enzyme in stomach, kidney, and testis extracts, and activity variation existed for this isozyme in kidney extracts. It is apparent that baboon ADH shares a number of features with the human ADH phenotype; however, several species-specific differences were observed, particularly for the liver and kidney class I isozymes and for stomach ADH.

Alcohol Dehydrogenase↗

PubMedDate not supplied

Tissue distribution, disposition, and metabolism of cyclosporine in rats.

Tissue distribution, disposition, and metabolism of 3H-cyclosporine were studied in rats after single and repeated oral doses of 10 and 30 mg/kg and after an iv dose of 3 mg/kg. The oral doses of 10 and 30 mg/kg were dissolved in polyethylene glycol 200/ethanol or in olive oil/Labrafil/ethanol. Absorption from both formulations was slow and incomplete, with peak 3H blood levels at 3-4 hr. Approximately 30% of the radioactive dose was absorbed, which is consistent with oral bioavailability data for cyclosporine. More than 70% of the radioactivity was excreted in feces and up to 15% in urine. Elimination via the bile accounted for 10 and 60% of the oral and iv doses, respectively. Since unchanged cyclosporine predominated in both blood and tissues at early time points, the half-lives of the distribution phases (t 1/2 alpha) of parent drug and of total radioactivity were similar. In blood, kidney, liver, and lymph nodes, t 1/2 alpha of cyclosporine ranged from 6-10 hr. Elimination of radioactivity from the systemic circulation was multiphasic, with a terminal half-life of 20-30 hr. 3H-Cyclosporine was extensively distributed throughout the body, with highest concentrations in liver, kidney, endocrine glands, and adipose tissue. The concentrations of both total radioactivity and parent drug were greater in tissues than in blood, which is consistent with the high lipid solubility of cyclosporine and some of its metabolites. Skin and adipose tissue were the main storage sites for unchanged cyclosporine. Elimination half-lives were slower for most tissues than for blood and increased with multiple dosing. The amount of unchanged drug was negligible in urine and bile.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Identification of the bile canalicular cell surface molecule GP110 as the ectopeptidase dipeptidyl peptidase IV: an analysis by tissue distribution, purification and N-terminal amino acid sequence.

This paper describes the tissue distribution, purification and N-terminal amino acid sequence of the bile canalicular cell surface molecule dipeptidyl peptidase IV. Immunoperoxidase staining of cryostat sections of rat liver with a monoclonal antibody, Medical Research Council OX-61, indicated specific binding to hepatocyte bile canalicular domains and brush borders of bile ducts. Additional staining was seen in other epithelial brush borders (small intestine, kidney, colon, pancreatic duct); acinar structures in salivary glands; endothelial structures and T cell areas in thymus, spleen and lymph node. The tissue distribution suggested that monoclonal antibody OX-61 binds to the ectoenzyme dipeptidyl peptidase IV. This was confirmed by depletion of dipeptidyl peptidase IV activity from tissue homogenates by monoclonal antibody OX-61 coupled to Sepharose. The molecule recognized by OX-61 was then purified from liver and kidney by monoclonal antibody affinity chromatography. The molecule had a molecular weight of 110 kD under reducing conditions. The purified molecule was subsequently analyzed for amino acid composition and N-terminal amino acid sequence. Thirty-one N-terminal amino acids were sequenced and indicated identity with part of the predicted N-terminus of the previously cloned bile canalicular molecule GP110. On review, other similarities between dipeptidyl peptidase IV and GP110 were detected: molecular weight, deglycosylated form and metabolic half-life. Finally, the recent cloning of dipeptidyl peptidase IV permitted a comparison between the molecule recognized by monoclonal antibody OX-61, GP110 and dipeptidyl peptidase IV. It is concluded that these three molecules are almost certainly identical.

Amino Acid Sequence↗

PubMed1988

Tissue distribution metabolism and excretion of 2,2',4,4',5-pentachlorodiphenyl ether in the rat.

The tissue distribution, metabolism and excretion of 14C-2,2',4,4',5-pentachlorodiphenyl ether (PCDE) were studied in the rat. Radioactivity was distributed in all tissues examined, with the highest concentrations being found in the fat followed by the skin, liver, kidney and muscle. Most of the radioactivity found in the tissues was due to unchanged PCDE. Decay of PCDE in the blood was fitted to a four-compartment pharmacokinetic model, and the last compartment had a half-life of 5.8 days. A total of 55% and 1.3% of an orally administered dose was excreted in feces and urine, respectively, in 7 days. More than 64% of the fecal radioactivity was due to unchanged PCDE, while hydroxylated PCDE accounted for 23%.

Animals↗

PubMed1991

Purification, some properties, and tissue distribution of a major lysosome-associated membrane glycoprotein (r-lamp-2) of rat liver.

We previously purified and characterized a major lysosomal membrane glycoprotein (r-lamp-1) from rat liver [Akasaki et al. (1990) Chem. Pharm. Bull. 38, 2766-2770]. The present study describes the purification of another major lysosomal membrane glycoprotein (r-lamp-2) from rat liver and compares the tissue distribution of r-lamp-1 and r-lamp-2 in rats. R-lamp-2 was purified to apparent electrophoretic homogeneity from rat liver by a simple method with a protein yield of approximately 4.0 micrograms/g wet weight of liver. The purification procedure includes: preparation of tritosomal membranes, extraction of tritosomal membranes with Lubrol PX, wheat germ agglutinin (WGA)-Sepharose affinity chromatography, and monoclonal antibody-Sepharose affinity chromatography. R-lamp-2 exhibited an Mr of 96,000 on SDS-PAGE and had an acidic pI of less than 3.5. R-lamp-2 contained 52.3% carbohydrates. Its carbohydrate moieties were composed of numerous sialyl complex type N-linked oligosaccharides and small amounts of O-linked oligosaccharides. Both r-lamp-1 and r-lamp-2 were detected in all rat tissues examined by immunoblot analyses, while their apparent molecular weights differed among the tissues. Immunological quantitative analysis showed that the protein concentrations of r-lamp-2 were consistently lower than those of r-lamp-1 in all the tissues tested. There was a significant correlation with a regression coefficient of 0.86 in the tissue distribution between r-lamp-1 and r-lamp-2. A good correlation was also observed in the tissue distribution between acid phosphatase and r-lamp-2.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1990

Pharmacokinetics, tissue distribution, and cell localization of [35S]methionine-labeled recombinant human and murine alpha interferons in mice.

The pharmacokinetics, tissue distribution, cell localization, and penetration into tumor xenografts of recombinant [35S]methionine-labeled human alpha interferon (HuIFN-alpha) and murine alpha interferon (MuIFN-alpha) were examined in mice. Both interferons (IFNs) were removed from the blood in a rapid biphasic manner; HuIFN-alpha was cleared faster than MuIFN-alpha. Tissues were analyzed for radioactivity and over 90% of the IFNs was accounted for. The IFNs were detected predominantly in liver, kidney, gastrointestinal tract, pancreas, spleen, and lung. The levels of MuIFN-alpha compared with HuIFN-alpha were greater in the liver, spleen, and lung and less in the kidney, pancreas, and gastrointestinal tract. Heart, brain, testes, thymus, lymph nodes, fat, skin, and skeletal muscle contained much lower but measurable levels of both IFNs. There was penetration of HuIFN-alpha into tumor xenografts. The pharmacokinetics of IFN-alpha were independent of the strain of mouse, BALB/c or CBA, immune deprivation, or the presence of a tumor xenograft. Autoradiography of tissue sections from mice given injections of HuIFN-alpha or MuIFN-alpha indicated focal radioactivity in proximal convoluted tubules in the kidney and diffuse radioactivity in the liver, gastrointestinal tract, and pancrease. MuIFN-alpha, but not HuIFN-alpha, showed intense localization in cells in hepatic sinusoids, marginal zones in the spleen, and pulmonary alveolar walls, suggesting uptake by cells of the monocyte/macrophage lineage in these sites. The study shows the utility of biosynthetic labeling for pharmacokinetic studies of cytokines, clear differences in tissue distribution of IFN-alpha according to its species of origin, and targeting of homologous IFN-alpha to cells of the monocytic lineage.

Animals↗

PubMed1991

Tissue distribution of two major components of synaptonemal complexes of the rat.

In this paper we describe an analysis of the tissue distribution of two recently identified components of synaptonemal complexes (SCs), an Mr 125,000 and an Mr 190,000 protein, in the male rat by immunoblot analysis and immunocytochemical techniques. We compared the tissue distribution of these antigens with that of two earlier identified SC components, an Mr 30,000 and an Mr 33,000 polypeptide. For this purpose we used monoclonal antibodies (Mabs) that react exclusively with SCs in lysed spermatocytes, and that recognize the above mentioned antigens specifically in immunoblots of SC proteins or of nuclear proteins from spermatocytes; these were Mab IX9D5 (anti-190,000), Mab IX5B2 (anti-125,000), Mab II52F10 (anti-30,000 + 33,000), and Mab IX8G9 (anti-30,000 + 33,000). In the immunoblot experiments, we could detect the Mr 190,000 and 125,000 antigens exclusively in blots of SC proteins or nuclear proteins from spermatocytes; these antigens were not detectable in blots of nuclear proteins from liver, brain, spermatogonia or spermatids or in blots of proteins from mitotic chromosomes or nuclear laminae. With the anti- 30,000 + 33,000 Mabs we obtained essentially the same result, except that Mab IX8G9, but not II52F10, recognizes a small amount of Mr 30,000 antigen in blots of nuclear proteins from spermatids and spermatogonia. Although this might be ascribed to contamination of the isolated spermatids and spermatogonia, we cannot exclude that a small amount of Mr 30,000 antigen is present in these cells. In the immunofluorescence analysis, the testis was the only tissue that reacted detectably with the above antibodies. Within the testis, spermatocytes and some early spermatids were the only cell types that contained detectable amounts of antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1987

Tissue distribution and elimination of trichlorobenzenes in the rat.

The tissue distribution and excretion of three trichlorobenzene isomers (TCB) were investigated in the rat. Single doses of TCBs were administered orally to groups of 5 fasted rats at 10 mg/kg body weight. Serial sacrifices were carried out and the radioactivity contents were determined in tissues and blood. For all three TCB isomers, radioactivity appeared in the blood and tissues at 0.5 h, and peaked around 2-4 h after dosing. Fat, skin, and liver had high concentrations of the parent compound while kidney and muscle had high levels of metabolites. Elimination of TCB from tissues and blood can best be described by a two-compartmental open pharmacokinetic model. The terminal half-lives were 145, 93 and 68 h for 1,2,3-, 1,2,4 and 1,3,5-TCB isomer respectively. Ninety-five percent of the administered 1,2,3- and 89% of the 1,3,5-isomers were eliminated within 48 h in the urine and feces with the former being the major route.

Animals↗

PubMed1988

Tissue distribution and developmental expression of protein kinase C isozymes.

Protein kinase C is a ubiquitous enzyme found in a variety of mammalian tissues and is especially highly enriched in brain and lymphoid organs. Based on biochemical and immunological analyses, we have identified three types of protein kinase C isozyme (designated types I-III) from rat brain. Monospecific antibodies against each of the protein kinase C isozymes were prepared for the determination of tissue distribution, subcellular localization, and developmental changes of these enzymes. The various protein kinase C isozymes were found to be distinctively distributed in different tissues: the type I enzyme in brain; the type II enzyme in brain, pituitary and pineal glands, spleen, thymus, retina, lung, and intestine; and the type III enzyme in brain, pineal gland, retina, and spleen. The rat brain enzymes were differentially distributed in different subcellular fractions. The type I enzyme appeared to be most lipophilic and was recovered mostly in the particulate fractions (80-90%) regardless of the EGTA- or Ca2+-containing buffer used in the homogenization. Significant amounts (30-40%) of the type II and III enzymes were recovered in the cytosolic fraction with EGTA-containing buffer. The expressions of different protein kinase C isozymes appear to be differently controlled during development. In rat brain, both type II and III enzymes were found to increase progressively from 3 days before birth up to 2-3 weeks of age and remained constant thereafter. However, the expression of the type I enzyme displayed a different developmental pattern; it was very low within 1 week, and an abrupt increase was observed between 2 and 3 weeks of age. In thymus, the type II enzyme was found to be maximal shortly after birth; whereas the same kinase in spleen was very low within 2 weeks of age, and a significant increase was observed between 2 and 3 weeks. These results demonstrate that protein kinase C isozymes are distinctively distributed in different tissues and subcellular locales and that their expressions are controlled differently during development.

Animals↗

PubMed1975

Tissue distribution of EDTA encapsulated within liposomes of varying surface properties.

Liposomes containing ethylenediaminetetraacetic acid (EDTA) were prepared with different surface properties by varying the liposomal lipid constituents. Positively charged liposomes were prepared with a mixture of phosphatidylcholine, cholesterol, and stearylamine. Negatively charged liposomes were prepared with a mixture of phosphatidylcholine, cholesterol, and phosphatidylserine. Neutral liposomes were prepared with phosphatidylcholine alone, dipalmitoyl phosphatidylcholine alone, or with a mixture of phosphatidylcholine and cholesterol. Distribution of 14C-labeled EDTA were determined in mouse tissues from 5 min to 24 h after a single intravenous injection of liposome preparation. Differences in tissue distribution were produced by the different liposomal lipid compositions. Uptake of EDTA by spleen and marrow was highest from negatively charged liposomes. Uptake of EDTA by lungs was highest from positively charged liposomes; lungs and brain retained relatively high levels of EDTA from these liposomes between 1 and 6 h after injection. Liver uptake of EDTA from positively or negatively charged liposomes was similar; the highest EDTA uptake by liver was from the neutral liposomes composed of a mixture of phosphatidylcholine and cholesterol. Liposomes composed of dipalmitoyl phosphatidylcholine produced the lowest liposomal EDTA uptake observed in liver and marrow but modrate uptake by lungs. Tissue uptake and retention of EDTA from all of the liposome preparations were greater than those of non-encapsulated EDTA. The results presented demonstrate that the tissue distribution of a molecule can be modified by encapsulation of that substance into liposomes of different surface properties. Selective delivery of liposome-encapsulated drugs to specific tissues could be effectively used in chemotherapy and membrane biochemistry.

Animals↗

PubMed1985

[Evaluation of the clinical effect and tissue distribution of cefpimizole in the field of gynecology].

Cefpimizole (AC-1370) was administered to 5 cases with uterine myoma before hysterectomy, and tissue distribution was determined. AC-1370 was also administered to 5 cases with gynecological infections. The following results were obtained. One gram of AC-1370 was administered from 43 to 299 minutes before hysterectomy, tissue distribution of AC-1370, such as ovary, oviduct, myometrium, cervix uteri, and portio vaginalis was showed the highest level (30.0 approximately 49.5 micrograms/g) at 43 minutes after administration, and these were 39.0 approximately 64.4% of the concentration in uterine arterial blood. Tissue concentration of AC-1370 was then gradually decreased following with the decreasing of the concentration in uterine arterial blood. AC-1370 was administered to 3 cases with pyometra, 1 case with Bartholin abscess, 1 case with adnexitis. The clinical efficacy was good in all 5 cases. Bacteriological study revealed that A. faecalis and E. coli were eradicated, but B. fragilis was persisted. No side effect was observed in all cases.

Adult↗

PubMed1990

Tissue distribution of radioiodinated neoglycoproteins and mammalian lectins.

Quantitation of tissue distribution of radioiodinated neoglycoproteins 1 h after intravenous injection into mice allowed to evaluate their suitability to uncover potential selectivity in tracer retention. Variations within the panel of neoglycoproteins were introduced to the carbohydrate determinant, its density and linkage to the carrier. Five arrays of neoglycoproteins, encompassing up to twelve different carbohydrate moieties were used. The individual response on the level of organ content showed differences, accounted for by carbohydrate structure and density. However, increase in sugar density eventually caused general decrease in tissue retention, emphasizing the importance of synthetic parameters. Attachment of sugar residues to the spacer via primarily the C-6 group of monosaccharides led to rather prolonged survival in circulation of the resulting neoglycoprotein compared to the application of neoglycoproteins with p-aminophenyl glycosides as derivatives for coupling. Besides applying neoglycoproteins tissue uptake was also measured for several organs, when four mammalian lectins were employed as radiotracers. These lectins bind to cellular carbohydrate ligands, namely beta-galactosides, alpha-fucosides or heparin. Differences were measured for retention in liver, kidneys, spleen, stomach, thymus and bone marrow. The distinct properties of different tissues with respect to binding of neoglycoproteins as well as to endogenous lectins, exhibiting a certain degree of selectivity, are a step within the framework to attempt to therapeutically exploit the carrier potential of probes by recognitive protein-carbohydrate interactions.

Animals↗

PubMed1990

The effects of thiamin on the tissue distribution of lead.

The effects of thiamin on the tissue distribution of lead were evaluated in Sprague-Dawley rats exposed to 1000 ppm lead acetate in drinking water and treated daily with thiamin (25 or 50 mg kg-1 body weight, i.p.), calcium ethylenediamine tetraacetic acid (50 mg kg-1 body weight, i.p.) or their combination for 8 weeks. The subtoxic dose of lead did not alter weight gains, feed and water consumption during the treatment period. Thiamin decreased the blood (P less than 0.0001), liver (P less than 0.0001) and kidney (P less than 0.0001) concentrations of lead. Thiamin (50 mg kg-1 body weight) reduced the lead concentrations in tissues more effectively than thiamin (25 mg kg-1 body weight). The combined treatment was more effective than the respective individual treatments.

Animals↗

PubMed1985

Autoradiography of tissue distribution of the IIA constituent of the pristinamycins.

The tissue distribution of a radioactive analogue of the IIA constituent of the pristinamycins was studied in female mice by autoradiography. Examination of slides and photographs discloses the presence of the antibiotic on the skin and in the bone marrow only a short time after injection. Elimination of the antibiotic is quick and is mainly through the digestive tract.

Animals↗

PubMedDate not supplied

Disposition and tissue distribution of angiopeptin in the rat.

The disposition and tissue distribution of angiopeptin, a long-acting octapeptide analogue of somatostatin, were studied in rats following single iv and sc administration of the drug. Similar plasma levels and excretion values of angiopeptin were observed by using radioimmunoassay and radiolabeling techniques. Angiopeptin was absorbed fairly rapidly, with a mean peak plasma level of 25 +/- 4.1 ng/ml at 10-15 min after administration. The kinetics of angiopeptin following sc administration closely resembled those following iv administration due to rapid absorption. The pharmacokinetics of angiopeptin can be described by a two-compartment model. The plasma half-life of the drug ranged from 2.6-2.9 hr when administered sc and 1.98-2.5 hr when given iv. Distribution of angiopeptin was rapid, with the highest concentration appearing in the liver. Half-lives in the liver and bile were short. Most of the drug was excreted in the feces via the bile, while approximately 10% was excreted in the urine. Angiopeptin was also found to be secreted in the saliva. TLC and HPLC of blood, urine, feces, and bile samples did not reveal the presence of any metabolites. In conclusion, the in vivo fate of angiopeptin is characterized by little or no hepatic metabolism and rapid biliary excretion.

Amino Acid Sequence↗