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PubMed2000

Tissue distribution of bovine cystatin C analysed by in situ hybridisation.

Cysteine proteinase inhibitors of the cystatin superfamily have been identified in many living organisms. However, knowledge of the tissue distribution of such inhibitors is limited. To elucidate this distribution in mammals, we have investigated the expression of the gene for cystatin C, belonging to cystatin family II, in several bovine tissues. In situ hybridisation with a digoxigenin-labelled cRNA probe demonstrated a high concentration of bovine cystatin C mRNA in the secretory epithelial cells of the choroid plexus, and also intense staining in cells of lymphoid tissue and in Sertoli cells. Cystatin C mRNA was also present in scattered neurons and glial cells throughout the cerebrum and the cerebellum. In the submandibular gland, specific mRNA was found mainly in striated intralobular ducts and interlobular ducts. The expression of cystatin C in brain tissue is of particular interest, as the inhibitor appears to be involved in certain neurological diseases. The main production of cystatin C within the brain is believed to be by astrocytes. However, this work shows that also neurons from young, normal individuals express cystatin C.

Animals↗

PubMed2005

Congener-specific tissue distribution of aroclor 1254 and a highly chlorinated environmental PCB mixture in rats.

Polychlorinated biphenyl (PCB) mixtures were synthesized and marketed in Eastern European countries, but little is known abouttheir composition, distribution, ortoxicity. PCB-contaminated soil from the former production site of the Polish PCB mixture Chlorofen was collected, and the PCBs were extracted. An in vivo study was performed to investigate the PCB tissue distribution and biochemical effects of this soil extract in immature male Sprague-Dawley rats. Rats were administered 0.05 mmol/kg soil-extracted PCBs or Aroclor 1254 and sacrificed 7 days later, and congener-specific PCB profiles in selected tissues were determined. Distribution of SigmaPCBs (sum of 120 congeners) in tissues was primarily a function of lipid content of the tissues, except for the spleen, which retained more PCB than other tissues. Multivariate analysis of the PCB congener data showed that (a) congener profiles in tissues had changed, as compared to the parent mixture; (b) disposition and redistribution of individual congeners in vivo differed between both mixtures; and (c) more highly chlorinated congeners were retained in the spleens of both treatment groups. Differences in the induction of cytochrome P-450 1A and 2B subfamilies reflected the homologue composition of the respective mixtures and predict a different toxicity profile for Chlorofen than for Aroclor 1254.

Adipose Tissue↗

PubMed1983

Effects of dose and dosing regimen on tissue distribution and elimination kinetics of [14C] dithiobiuret in rats.

[14C] Dithiobiuret (DTB)-derived radioactivity is eliminated by adult male rats with an approximate plasma half-life of 8-10 hr. About 65-75% of an i.p. dose appears in the urine within 24 hr after treatment and about 2-4% appears in the feces during the same time period. Less than 1% is recovered as [14C] carbon dioxide in expired air. The elimination kinetics for plasma and the % dose of DTB eliminated as the parent compound and metabolites in urine and feces, respectively, are the same for 1 mg/kg and 25 mg/kg acute treatments and for 1 mg/kg/day chronic treatment. Dose and dosing regimen dependent changes in tissue distribution are evident for most tissues with the thyroid gland, lung, stomach and fat being the most affected. Accumulation of DTB or its metabolites in the thyroid gland is greater than in any other tissue and is saturable at 25 mg/kg. The lung and stomach have a lower concentration of [14C] DTB equivalents than the thyroid, but they show the greatest relative increase in concentrations, about 5 fold, when [14C] DTB is administered chronically. Conversely, fat does not accumulate DTB-derived radioactivity during chronic dosing. These findings suggest that DTB metabolism is altered by changes in dose and dosing regimen.

Animals↗

PubMed1991

Clinical pharmacology, metabolism, and tissue distribution of 90Y-labeled monoclonal antibody B72.3 after intraperitoneal administration.

B72.3 is a murine monoclonal antibody that recognizes a high-molecular-weight tumor-associated glycoprotein (TAG-72). Nine patients with TAG-72-positive ovarian carcinoma or papillary serous carcinoma of the peritoneum received an intraperitoneal infusion of 2, 4, or 10 mg B72.3 labeled with 0.5-1.2 (mean, 0.8) mCi 90Y. All patients had laparotomy, with multiple tissue and tumor samples removed 3-7 days later. The concentration of the total 90Y label in peritoneal fluid cleared with an extrapolated half-life of 68.6 +/- 4.5 hours. A low-molecular-weight 90Y-labeled species of metabolite was identified by high-performance liquid chromatography. The concentration of this low-molecular-weight species initially increased in the peritoneal fluid, with a half-life of 0.9 hour, and was rapidly cleared from the peritoneal cavity, with a half-life of 23.1 hours. Both the 90Y-labeled metabolite and the 90Y-labeled B72.3 were absorbed into the plasma, with half-lives of 16 +/- 2.2 hours and 25 +/- 5 hours, respectively. The clearance half-lives for these agents in plasma were 25 +/- 3 hours for the metabolite and 42 +/- 17 hours for B72.3. Approximately 8%-11% of the total injected 90Y label appeared in urine over 72 hours. Most of the label (about 70%) was present as the 90Y-labeled metabolite, but about 30% of the 90Y label in urine appeared identical to the authentic 90Y-labeled B72.3 standard when assayed by chromatography. Tissue distribution studies showed that normal tumor tissue and omentum contained the highest content of 90Y (about 0.017% of the injected dose per gram), followed in descending order by liver, normal lymph nodes, peritoneum, bone, and fascia. The lowest concentrations of 90Y were found in rectus abdominis muscle, bone marrow, and fat. There was substantial heterogeneity in the uptake of the 90Y label into tumor sites among patients and among different sites within the same patient. No correlation could be demonstrated between the TAG-72 content and the amount of 90Y label found in tumor sites. Preliminary radiation dosimetry estimates suggest that the tumor sites received about 82.8 cGy for each millicurie of 90Y administered. Thus, if an adequate total radiation dose can be achieved, 90Y-labeled B72.3 should be therapeutically useful for treating diffuse intraperitoneal disease.

Adult↗

PubMed1991

Tissue distribution and bioactivity of amphotericin B administered in liposomes to cancer patients.

Amphotericin B concentration was measured by high-pressure liquid chromatography (HPLC) and by bioassay in tissues of 11 cancer patients who died from infection and/or their underlying disease after having received amphotericin B entrapped into sonicated liposomes (ampholiposomes). These concentrations were compared to those measured in 28 patients who had only received the commercially available preparation of amphotericin B-Na deoxycholate complex (Fungizone). The fungistatic and fungicidal titres of the tissue homogenates were also evaluated using two strains of Candida spp. and one strain of Cryptococcus neoformans to determine the bioactivity of amphotericin B incorporated in our liposomes. Tissue concentrations varied with the tested tissues and were correlated with the total dose of amphotericin B administered whether given as amphotericin B-Na deoxycholate or ampholiposomes. Amphotericin B concentrations measured by bioassay in tissue methanolic extracts reached 58-81% of concentrations measured by HPLC, whereas only 15-41% was recovered from the unextracted homogenates. Fungicidal titres were seldom measured in tissues, but fungistatic titres were observed and were linearly correlated with amphotericin B concentration measured by HPLC. These results were similar for the patients who received only amphotericin B-Na deoxycholate and for those who received both preparations (amphotericin B-Na deoxycholate and ampholiposomes). Our results suggest that the tissue distribution of amphotericin B is not significantly modified by the type of preparation (deoxycholate complex or liposomes) and that most of the tissue-bound amphotericin B is not bioactive. However, higher daily doses of amphotericin B can be administered safely when incorporated in liposomes and therefore high tissue concentrations may be obtained more rapidly with ampholiposomes than with amphotericin B-Na deoxycholate.

Adult↗

PubMed1986

The tissue distribution of L-ascorbic acid and dehydro-L-ascorbic acid in the guinea pigs injected intravenously with dehydro-L-ascorbic acid.

The tissue distribution of L-ascorbic acid (AsA) and dehydro-L-ascorbic acid (DAsA) in guinea pigs injected with DAsA intravenously was examined using high-performance liquid chromatography. DAsA injected into guinea pigs fed normal diets containing AsA (control group) was readily taken into erythrocytes, and AsA contents of plasma and other tissues rapidly increased after DAsA injection. In animals fed vitamin C-deficient diets, DAsA was also detected in erythrocytes; however, the increase of AsA in their tissues was considerably less than that of control group. From these results, it was suggested that utilization of DAsA as AsA in vitamin C-deficient guinea pigs was less than that of control animals, and the reduction mechanism of DAsA to AsA in vitamin C-deficient guinea pigs may have differed from that of control groups.

Administration, Oral↗

PubMed1991

Uneven tissue distribution of minor histocompatibility proteins versus peptides is caused by MHC expression.

Naturally processed minor histocompatibility (H) peptides corresponding to H-4b, H-Y, and an unmapped BALB.B minor H gene were quantified in a relative way in 15 different tissues of male BALB.B mice. For one of these minor H antigens, we could also determine the relative content of the respective protein. For each minor H peptide, an individual tissue distribution was found. Tissues expressing little or no MHC (major histocompatibility complex), like brain, contained only small amounts of minor H peptides or none at all, although the same tissues contained minor H protein in substantial quantities. By contrast, Kb-expressing brains from mice transgenic for Kb under control of the glial acidic protein promoter contained both minor H peptide and protein in high amounts. Thus, the expression of minor H peptides in a given tissue is dependent on coexpression of the restricting MHC class I molecules.

Animals↗

PubMed1992

High-performance liquid chromatographic analysis of amphotericin B in plasma, blood, urine and tissues for pharmacokinetic and tissue distribution studies.

A sensitive and reproducible high-performance liquid chromatographic method was developed to assay ampherotericin B in plasma, blood, urine and various tissue samples. Amphotericin B was isolated from each sample matrix by solid-phase extraction (Bond-Elut). The eluate from Bond-Elut containing amphotericin B was injected onto a reversed-phase C18 column (Waters, mu Bondpak, 10 microns, 300 mm x 3.9 mm I.D.) with a mobile phase of 45% acetonitrile in 2.5 mM Na2EDTA at 1 ml/min. Detection of amphotericin B was by ultraviolet absorption at 382 nm. Blood and tissues were homogenized and extracted with methanol prior to Bond-Elut extraction. The extraction efficiencies of amphotericin B from plasma, blood and tissues were approximately 90, 70 and 75%, respectively. The sensitivity of the assay was less than or equal to 5 ng/ml for plasma, less than or equal to 25 ng/ml for blood, 2.5 ng/ml for urine and 50 ng/g for tissues. The linearity of the assay method was up to 2.5 micrograms/ml for plasma, 5 micrograms/ml for blood, 500 ng/ml for urine and 500 micrograms/g for tissues. The assay was reproducible with an intra-day coefficient of variation (C.V., n = 3) of less than 5% in general for plasma, blood and tissues. The inter-day C.V. of the assay was less than 5% for plasma (n = 5), less than 10% for blood (n = 4) and less than 5% for tissues (n = 3). The overall variability in the urine assay was generally less than 10%. This method has demonstrated significant improvement in the sensitivity and reproducibility in assaying amphotericin B in plasma and especially in blood, urine and tissues. We have employed this assay to compare the pharmacokinetic and tissue distribution profiles of amphotericin B in rats and dogs following administration of Fungizone and ABCD (amphotericin B-cholesteryl sulfate colloidal dispersion), a lipid-based dosage form. In addition, the assay method for plasma and urine samples can also be applied to pharmacokinetics studies of amphotericin B in man.

Amphotericin B↗

PubMed1989

Effects of thyroparathyroidectomy and of thyroxin and calcitonin on the tissue distribution of twelve elements in the rat.

The effects of thyroparathyroidectomy (TPTY) and of replacement therapy using thyroxin (T4) and calcitonin (CT) on the tissue distribution of elements were studied in the rat under semichronic conditions. The elements Na, K, Ca, Mg, Fe, S, P, Rb, Sr, Mn, Cu, and Zn were determined in whole blood, plasma, brain, liver, heart, kidney, skeletal muscle, and bone. TPTY modified concentrations of all elements tested but only small changes were observed for K, Mg, S, and P. The mineral bone composition was slightly modified, 28 d after TPTY, whereas plasma was the most altered. The consequences of TPTY were corrected fairly well by T4 for Na, Cu, Zn, Fe, and S, and by CT for K, P, Rb but with less efficiency for Ca. This study revealed that hormones of the thyroid gland, mainly T4, play an important role in the plasma and tissue balance of elements. It is suggested that T4 participates in tissue fixation of Cu, Zn, and Fe and that CT influences phosphoremia and cellular Ca binding.

Animals↗

PubMed1995

Tissue distribution of the DNA binding oncoprotein Maf during chicken development.

To assess the normal function of the c-maf protooncogene product, we examined its tissue distribution during fetal growth and organogenesis of the chicken using an immunohistochemical technique. Nuclei of neuronal cells in the optic lobe and in the outer granular layer of the cerebral cortex were efficiently stained by anti-Maf serum throughout all developmental stages examined. In the lung, mesenchymal cells were stained intensely by the antiserum, with the most intense staining around embryonic day 15. During the embryonic period, nuclei of mesenchymal cells in the perichondrial and periosteal tissues as well as intestinal submucosa were also stained specifically by the antiserum. In addition, we detected substantial Maf immunoreactivity in nuclei of renal glomerular and proximal-tubular epithelial cells. These results suggest that c-Maf protein plays some important roles in the development of the central nervous system and tissues of mesodermal origin such as connective and renal tissues.

Animals↗

PubMed2002

Mechanism for the tissue distribution of grepafloxacin, a fluoroquinolone antibiotic, in rats.

This study was carried out to investigate the most important factor(s) governing the tissue distribution of grepafloxacin (GPFX), a fluoroquinolone antibiotic, in rats. The tissue-to-blood concentration ratio (K(p)) of GPFX at steady state during constant infusion was highest in the lung, followed by the pancreas, kidney, and spleen. After bolus injection, GPFX was efficiently taken up by most of the organs examined, the uptake clearance other than the lung being almost blood flow-limited. Approximately 10% of the intravenously injected dose was rapidly trapped by the lung, but GPFX distribution rapidly decreased within 30 s due to the washout by the plasma flow. Thus, the higher distribution of GPFX to the lung compared with the other organs cannot be accounted for by a difference in its uptake or efflux. Subcellular fractionation after the infusion indicated that GPFX is primarily distributed to the organelle fractions in most organs, 60% of lung-associated GPFX being recovered in the nucleus and plasma membrane fraction. Such subcellular distribution in the lung was proportional to the phosphatidylserine (PhS) content of each fraction. The steady-state K(p) value in each tissue in vivo also correlated with the tissue content of PhS. GPFX preferentially binds to PhS, compared with other phospholipids, and this binding was inhibited by weakly basic drugs, such as quinidine, imipramine, and propranolol, that have also been reported to bind to PhS. The association of GPFX with PhS synthase transformants of Chinese hamster ovary (CHO-K1) cells depends on the PhS content of each cell line, this association being also inhibited by basic drugs. These results suggest that binding of GPFX to PhS is the major determinant of the high distribution of GPFX to the lung.

Animals↗

PubMed1990

2,3,7,8-Tetrachlorodibenzo-p-dioxin pretreatment of female mice altered tissue distribution but not hepatic metabolism of a subsequent dose.

Lipid partitioning of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inadequately explains its tissue distribution since higher concentrations occur in liver than fat except at high doses. This study provides in vivo evidence that an inducible, saturable system plays a predominant role in disposition of [14C]TCDD in female mice at doses between 5 and 20 micrograms/kg. Female C57BL/6J mice were gavaged with 0, 5, or 15 micrograms TCDD/kg, received a subsequent gavage of 5 or 20 micrograms [14C]TCDD after 6 days, and were killed 1 day later. In mice pretreated with 5 and 15 micrograms TCDD/kg and subsequently dosed with 20 micrograms [14C]TCDD/kg, liver weight and [14C]TCDD concentration increased. Total liver [14C]TCDD burden increased about 50% in both pretreatment groups. Concentrations of [14C]TCDD in kidney, fat, heart, lung, gastrointestinal tract, but not plasma or splenic lymphocytes, decreased in a reciprocal manner. Alterations in absorption, concentrations of polar metabolites of [14C]TCDD in liver, and hepatic lipid content failed to explain these results. About 97% of hepatic 14C was hexane extractable. HPLC of this extract indicated [14C]TCDD was the only significant nonpolar form of radiolabel in liver. In mice pretreated with 5 micrograms TCDD/kg and subsequently dosed with 5 micrograms [14C]TCDD/kg, a more marked pretreatment disposition response was observed. These results are consistent with a predominant role for an inducible, high affinity, low capacity system in whole animal pharmacokinetics of TCDD.

Animals↗

PubMed2001

In vivo toxicity, pharmacokinetic features and tissue distribution of N-[2-(2,5-dimethoxyphenylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea (HI-236), a potent non-nucleoside inhibitor of HIV-1 reverse transcriptase.

N-[2-(2,5-Dimethoxyphenylethyl)]-N'-[2-(5-bromopyridyl)]-thiourea (HI-236, CAS 233271-65-3) possesses potent anti-viral activity against zidovudine-sensitive as well as multidrug-resistant HIV-1 (human immunodeficiency virus) strains. The purpose of the present study was to examine in vivo toxicity, pharmacokinetic features and tissue distribution of HI-236 in mice. HI-236 had an elimination half-life of 85.8 min after i.v. administration and 86.6 min after i.p. administration. The systemic clearance of HI-236 was 4337 ml/h/kg after i.v. administration and 10,130 ml/h/kg after i.p. administration. Following i.v. injection, HI-236 rapidly distributed to and accumulated in multiple tissues with particularly high accumulation in lung, adipose tissue, skin, urinary bladder, adrenal gland and uterus + ovary. The concentration of HI-236 in brain tissue was comparable to that in the plasma, indicating that HI-236 easily crosses the blood-brain barrier. Following i.p. injection, HI-236 was rapidly absorbed with a tmax values of 5.6 min and showed linear pharmacokinetics within the dose range of 10-80 mg/kg. Following oral administration, HI-236 was absorbed with a tmax of 5.8 min. The intraperitoneal bioavailability was estimated at 42.9%, while the oral bioavailability was only 2.2%. The pharmacokinetic study described herein provides the basis for advanced pharmacodynamic study of HI-236.

Animals↗

PubMed1991

Porcine fatty acid synthase: cloning of a complementary DNA, tissue distribution of its mRNA and suppression of expression by somatotropin and dietary protein.

A cDNA for porcine fatty acid synthase was isolated and used to examine the tissue distribution of fatty acid synthase mRNA within the pig and to determine the impact of recombinant porcine somatotropin (rpSt) and the level of dietary protein on fatty acid synthase mRNA abundance in pig liver and adipose tissue. A 1.5-kb cDNA representing the thioesterase domain of porcine fatty acid synthase was isolated from a lambda gt 11 liver cDNA library. Northern analysis with total RNA extracted from adipose tissue, liver, heart, lung, kidney and intestine revealed a single major fatty acid synthase mRNA species of 8-9 kb. The amount of fatty acid synthase mRNA in hepatic tissue was 25% of the amount in adipose tissue, which suggests that the liver may be a significant site of fatty acid synthesis in the pig. Fatty acid synthase mRNA abundance was significantly reduced in the adipose tissue (P less than 0.01) and the liver (P less than 0.1) by chronic daily administration (60 micrograms/kg) of rpSt. In addition, increasing the amount of dietary protein decreased (P less than 0.1) the abundance of fatty acid synthase mRNA in adipose tissue but had no effect on liver fatty acid synthase expression. In contrast, the abundance of adipose fatty acid binding protein mRNA was unaffected by rpSt or dietary protein. These data indicate that the reduction in the level of fatty acid synthase mRNA is a factor in the pSt-mediated suppression of fatty acid synthesis in porcine adipose tissue.

Adipose Tissue↗

PubMed1993

Developmental gene expression and tissue distribution of the CHIP28 water-channel protein.

The CHIP28 water channel is a major component of red cell and renal tubule membranes; however, its ontogeny and tissue distribution remain undefined. Three patterns of expression were identified when CHIP28 mRNA was surveyed by in situ hybridization histochemistry in rats between embryonic day 14 and maturity. (i) CHIP28 mRNA and protein were very abundant in hematopoietic tissue and kidneys of mature rats, but strong expression did not occur until after birth, when it appeared in renal proximal tubules and descending thin limbs, red pulp of the spleen, and membranes of circulating red cells. (ii) CHIP28 mRNA was abundant in choroid plexus epithelium throughout fetal development and maturity. (iii) CHIP28 mRNA was transiently observed in periosteum, heart, vascular endothelium, and cornea during fetal development. The ontogeny of kidney and red cell CHIP28 expression coincides with the ability of kidneys to concentrate urine, suggesting that CHIP28 promotes water reabsorption in the proximal nephron and provides red cell osmoregulation needed for passage through the hypertonic medulla. Its presence in the choroid plexus suggests that CHIP28-mediated water transport contributes to secretion of cerebrospinal fluid. The functional role of CHIP28 in developing bone, heart, and eye is unclear. These findings further establish the general physiologic role of CHIP28 as a water channel involved in reabsorption, osmoregulation, and secretion. The studies also suggest other possible functions during fetal development and predict that complex mechanisms will be needed for regulation of CHIP28 gene expression in diverse tissues at distinct points in development.

Animals↗

PubMed2000

Structural and functional characteristics and tissue distribution pattern of rat OCTN1, an organic cation transporter, cloned from placenta.

This report describes the structure, function, and tissue distribution pattern of rat OCTN1 (novel organic cation transporter 1). The rat OCTN1 cDNA was isolated from a rat placental cDNA library. The cDNA is 2258 bp long and codes for a protein of 553 amino acids. Its amino acid sequence bears high homology to human OCTN1 (85% identity) and rat OCTN2 (74% identity). When expressed heterologously in mammalian cells, rat OCTN1 mediates Na(+)-independent and pH-dependent transport of the prototypical organic cation tetraethylammonium. The transporter interacts with a variety of structurally diverse organic cations such as desipramine, dimethylamiloride, cimetidine, procainamide, and verapamil. Carnitine, a zwitterion, interacts with rat OCTN1 with a very low affinity. However, the transport of carnitine via rat OCTN1 is not evident in the presence or absence of Na(+). We conclude that rat OCTN1 is a multispecific organic cation transporter. OCTN1-specific mRNA transcripts are present in a wide variety of tissues in the rat, principally in the liver, intestine, kidney, brain, heart and placenta. In situ hybridization shows the distribution pattern of the transcripts in the brain (cerebellum, hippocampus and cortex), kidney (cortex and medulla with relatively more abundance in the cortical-medullary junction), heart (myocardium and valves) and placenta (labyrinthine zone).

Amino Acid Sequence↗

PubMed2000

Tissue distribution of histo-blood group antigens.

The introduction of immunohistochemical techniques and monoclonal antibodies to specific carbohydrate epitopes has made it possible to study in detail the tissue distribution of histo-blood group antigens and related carbohydrate structures. The present paper summarizes the available data concerning the histological distribution of histo-blood group antigens and their precursor structures in normal human tissues. Studies performed have concentrated on carbohydrate antigens related to the ABO, Lewis, and TTn blood group systems, i.e. histo-blood group antigens carried by type 1, 2, and 3 chain carrier carbohydrate chains. Histo-blood group antigens are found in most epithelial tissues. Meanwhile, several factors influence the type, the amount, and the histological distribution of histoblood group antigens, i.e. the ABO, Lewis, and saliva-secretor type of the individual, and the cell- and tissue type. Oligosaccharides with blood-group specificity are synthesized by the stepwise action of specific gene-encoded glycosyltransferases. In general, this stepwise synthesis of histo-blood group antigens correlates with cellular differentiation. The H and the Se genes both encode an al-2fucosyltransferase, which is responsible for the synthesis of blood group antigen H from precursor disaccharides. A new model for the participation of the Se/H-gene-encoded glycosyl transferases in synthesis of terminal histo-blood group antigens in human tissues is proposed; the type and degree of differentiation rather than the embryologic origin determines whether it is the H or the Se gene-encoded transferases that influence expression of terminal histo-blood group antigens in tissues.

ABO Blood-Group System↗

PubMedDate not supplied

Tissue distribution, toxicokinetics and induction of hepatic drug metabolizing enzymes in male rats after a single s.c. dose of 3,4,3',4'-tetrachlorobiphenyl (PCB-77).

The tissue distribution and toxicokinetics of PCB-77 after a single s.c. dose of 6 mg/kg body weight was investigated in male adult rats as well as the concurrent induction of hepatic drug-metabolizing enzymes. During five days after treatment, the PCB-77 concentrations on fat weight basis in testis and in whole blood were found to be about in the same range as the concentrations in adipose tissue, whereas in liver fat PCB-77 accumulated. EROD and MROD activities were induced by about 8 and 4 times, respectively, during a period of two weeks after treatment. Concentrations in adipose tissue and in liver as well as the hepatic enzyme activities rapidly declined during the investigation period of eight weeks. An elimination half-life for PCB-77 of approximately 7-9 days was estimated.

Adipose Tissue↗