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PubMed1980

Tissue distribution of copper-labeled 3-ethoxy-2-oxobutyraldehyde bis (thiosemicarbazone) (Cu-64 KTS) in mice and rats: concise communication.

The antitumor activity of, 3-ethoxy-2-oxobutyraldehyde bis (thiosemicarbazone) (KTS), is related to the presence of copper(II) ion. We have studied the tissue distribution of Cu-64-labeled KTS in rats and mice carrying transplanted tumors to evaluate whether the uptake of the radioactivity in the tumor is adequate to warrant further investigation of the tracer as a tumor-seeking agent in patients. Four groups of three of four animals each were studied: (a) mice with fibrosarcoma; (b) mice with mammary adenocarcinoma; (c) rats with fibrosarcoma; and (d) rats with squamous cell carcinoma of the lung. The animals were killed at intervals of 0.25, 1, 4, 24, and 48 hr after i.v. injection of 1.6 X 10(-3) M Cu.KTS containing 3 to 18 muCi Cu-64. Blood, tumor, and six to ten additional tissues were counted for radioactivity. The mouse fibrosarcoma concentrated Cu-64, reaching 15% of the administered dose/g at 48 hr after injection. This suggests that for tumor scanning, the 61.7-hr Cu-67 might be more suitable as a label for KTS than the 12.7-hr Cu-64.

Animals↗

PubMed1998

Molecular cloning, functional expression and tissue distribution of rat acyl-coenzyme A:cholesterol acyltransferase.

Acyl-coenzyme A:cholesterol acyltransferase (ACAT) is an enzyme catalyzing the intracellular formation of cholesteryl esters from free cholesterol and fatty acyl-CoA. In the present study, we cloned rat ACAT cDNA and determined its tissue distribution. Rat ACAT cDNA, having a coding region of 1635 bp with its deduced protein sequence of 545 amino acids and two typical motifs such as signature sequences and leucine heptad motif, showed 83, 92 and 90% identity with human, mouse, and hamster ACAT, respectively. Expression of rat ACAT cDNA in A293 cells and CHO cells resulted in a 3.0 to 3.5-fold increase in the enzyme activity. Among twelve tissues examined, ACAT activity was highest in adrenal followed by liver and intestine while that of aorta was extremely low. The mRNA level was also the highest in adrenal among four tissues examined. However, in contrast to its high ACAT activity, the liver mRNA level was extremely low (adrenal >> intestine > aorta >> liver). Consistent with mRNA levels, immunohistochemical analyses with a specific ACAT antibody detected significant ACAT signals in adrenal and intestine but a negligible signal in liver. These results indicate that adrenal most abundantly expresses ACAT in rat. Furthermore, rat liver showed a high ACAT activity but an extremely low ACAT mRNA and negligible immunohistochemical reactivity, suggesting the presence of a structurally different ACAT protein(s) in rat liver.

Amino Acid Sequence↗

PubMed2003

cDNA cloning of chicken orexin receptor and tissue distribution: sexually dimorphic expression in chicken gonads.

Orexin-A and -B are known to stimulate food intake in mammals. However, the critical roles of orexins in birds are not fully understood, since orexins have no stimulatory effect on food intake in the chicken. To understand the physiological role(s) of orexins in birds, we have cloned chicken orexin receptor (cOXR) cDNA by RT-PCR, and analysed the tIssue distribution of OXR mRNA in the chicken. The cOXR cDNA is 1869 bp long and encodes 501 amino acids. The cloned cDNA for cOXR corresponds to the type 2 OXR in mammals, and shows approximately 80% similarity to those of mammals at the amino acid level. Expression analysis by RNase protection assay revealed OXR mRNA was distributed widely in brain regions, and expression in the cerebrum, hypothalamus and optic tectum were abundant. In peripheral tIssues, OXR mRNA was expressed in the pituitary gland, adrenal gland and testis, but no mRNA expression was observed in other tIssues examined. Furthermore, we found that the amount of cOXR mRNA was different between testis and ovary, while prepro-orexin mRNA is equally expressed in the gonads of both sexes in the chicken. These data indicate that the orexins have neuroendocrine actions in chickens, which are mediated through hypothalamic receptors as has been observed in mammals. In addition, orexin may have specific role(s) in the regulation of gonadal function in which sex-dependent mechanisms could be involved.

Amino Acid Sequence↗

PubMed2000

Tissue distribution and disposition kinetics of enrofloxacin in healthy and E. coli infected broilers.

Concentrations of enrofloxacin equivalent activity were determined by microbiological assay in the plasma of healthy and E. coli-infected broilers following single intravenous and oral administrations at 10 mg/kg. Tissue distribution and residue-depletion following multiple oral doses (10 mg/kg for 3 successive days) were investigated. Pharmacokinetic variables were determined using compartmental and non-compartmental analytical methods. Plasma enrofloxacin concentrations after intravenous dosing to healthy and infected birds were best described by a two-compartments model. Enrofloxacin concentrations in plasma of infected birds were lower than those of healthy ones. The disposition kinetics of intravenously administered drug in healthy and infected birds were somewhat different. The elimination half-life (t1/2 beta) was 4.75 vs. 3.63 h; mean residence time (MRT) was 6.72 vs 4.90 h; apparent volume of the central compartment (Vc) was 1.11 vs 1.57 l/kg; rate constant for transfer from peripheral to central compartment (k21) was 1.15 vs 1.41 h-1 and total body clearance (ClB) was 0.35 vs 0.53 l/h/kg in healthy and infected birds, respectively. After oral administration, the absorption half-life (t1/2abs) in the infected birds was significantly longer than in healthy birds, while elimination half-life (t1/2el) and MRT were significantly shorter. Bioavailability was higher in infected birds (72.50%) as compared to healthy ones (69.78%). Enrofloxacin was detected in the tissues of healthy and infected birds after daily oral dosing of 10 mg/kg for 3 days. It was more concentrated in liver, kidney, and breast muscle. The minimal inhibitory concentration (MIC) of enrofloxacin against E. coli was 0.064 microgram/ml. On the basis of maintaining enrofloxacin plasma concentrations over the MIC, a dose of 10 mg/kg given intravenously every 20.14 hrs or orally every 20.86 hrs should provide tissue concentrations effective against E. coli infection in chickens.

Administration, Oral↗

PubMed1995

Mean residence time of drugs administered non-instantaneously and undergoing linear tissue distribution and reversible metabolism and linear or non-linear elimination from the central compartment.

Based on disposition decomposition analysis (DDA), equations for the mean residence times (MRT) in the body are derived for a drug and its interconversion metabolite that undergo linear tissue distribution and linear or non-linear elimination from the central compartment after non-instantaneous administration of the drug. The MRT of the drug after non-instantaneous input can be related to the MRT of the drug after intravenous administration, the ratio of the total area under the plasma concentration-time curve of the drug after non-instantaneous administration to that after intravenous administration, the bioavailability of the drug, and the mean input time of the drug. Similar relationships also exist for the MRT of the interconversion metabolite after non-instantaneous input of the drug. The application of these equations to a non-linear reversible metabolic system is illustrated with computer simulations.

Biological Availability↗

PubMed2002

Pharmacokinetics and tissue distribution of a new partricin A derivative (N-dimethylaminoacetyl-partricin A 2-dimethylaminoethylamide diaspartate) in mice.

A single-dose trial in mice (1.25 mg/kg SPA-S-753 or 1 mg/kg amphotericin B [AmB] by intravenous route) was performed to study the pharmacokinetics, tissue distribution, and urinary excretion of a new polyene, SPA-S-753 (N-dimethylaminoacetyl-partricin A 2-dimethylaminoethylamide diaspartate), in comparison with AmB. Antibiotic concentrations were determined by microbiological assay (agar diffusion method). The elimination half-lives in serum were 15.1 and 19.8 h, respectively, for SPA-S-753 and AmB; the area under the curve from 0 to infinity values were 49.3 for SPA-S-753 and 23.6 microg. h/mL for AmB, because of the higher serum levels of SPA-S-753 found just after administration. The tissue concentrations of SPA-S-753 were lower than those of AmB in liver and lungs but higher in the kidneys. The urine concentrations of SPA-S-753 and the percent of the administered dose recovered from the urine were quite low in mice, whereas those of AmB were higher.

Amphotericin B↗

PubMed1997

Tissue distribution and subcellular localization of rabbit liver metalloendopeptidase.

We have previously isolated rabbit liver microsomal metalloendopeptidase (MEP) as a candidate for the processing enzyme of vitamin K-dependent plasma proteins. A cDNA coding for MEP has revealed that it is structurally related to metalloendopeptidase-24.15, which catalyzes the proteolytic processing of several bioactive peptides. In this study we examined the tissue distribution and subcellular localization of MEP by light and electron microscopic immunohistochemical methods, in addition to Northern blot analysis. Chicken polyclonal antibodies were raised by using synthetic peptides AG1 (Met31-Asn46) and AG3 (Asp537-Gly551) derived from the sequence of MEP. Both anti-AG1 and anti-AG3 antibodies reacted specifically with MEP, as judged by Western blotting and immunohistochemical methods. Both antibodies gave an identical staining distribution, which was localized on the luminal cell surfaces and in the cytoplasm of the following organs: liver, brain, lungs, kidneys, esophagus, stomach, duodenum, pancreas, placenta, epididymis, uterus, ovary, and oviduct. Northern blot analysis revealed that the expression of MEP mRNA is similar to its immunohistochemical distribution except in the heart. These results suggest that MEP may participate more closely in a degradation role in peptide metabolism in various tissues than in a processing role of the proprotein, like metalloendopeptidase-24.15.

Amino Acid Sequence↗

PubMed2001

Uptake, tissue distribution, and fate of inhaled carbon tetrachloride: comparison of rat, mouse, and hamster.

Carbon tetrachloride is hepatotoxic in rats, mice, and hamsters. However, rats are less sensitive to the hepatotoxic effects of CCl(4) than the other two species. The purpose of this study was to compare the uptake, tissue distribution, and elimination of CCl(4) by these three rodent species. Groups of 20 F344/Crl BR rats, B6C3F(1) mice, and Syrian hamsters were exposed by nose-only inhalation for 4 h to 20 ppm (14)C-labeled CCl(4). The fate of (14)C was followed in tissues, excreta, and exhaled breath for 48 h after the exposure. At the end of the exposure, concentrations of CCl(4) equivalents (CE) in tissue were highest in liver of rats and mice, but highest in fat for rats. The liver received the highest dose of CCl(4) equivalents with the following species ranking: mouse > hamster > rat. Patterns of CE elimination were species and tissue dependent, with the majority of elimination occurring within 48 h after exposure. Rats eliminated less radioactivity associated with metabolism ((14)CO(2), urine and feces) and more radioactivity associated with parent compound (exhaled activity trapped on charcoal) than did mice or hamsters. The results indicate that ranking of species sensitivity to the hepatotoxic effects of inhaled CCl(4) correlates with CE dose to liver and with the ability to metabolize CCl(4).

Animals↗

PubMed2002

Uptake across the blood-brain barrier and tissue distribution of enterostatin after peripheral administration in rats.

Enterostatin, the N-terminal activation pentapeptide of procolipase that is produced by the pancreas, reduces food intake from high-fat diet when injected either peripherally or centrally to rats. We investigated uptake across the blood-brain barrier (BBB) and tissue distribution of enterostatin by giving radioactive-labeled enterostatin (3H-VPDPR) intravenously. Low levels of 3H-VPDPR were detected in many areas of the brain, with greatest radioactivity in the frontal cortex, hippocampus and cerebellum. Radioactivity was found in the plasma and all tissues, with the highest amount detected in the pancreas.

Animals↗

PubMed1999

Tissue distribution of tramadol and metabolites in an overdose fatality.

Tramadol (Ultram) is a centrally acting, synthetic analgesic agent. Although it has some affinity for the opiate receptors, tramadol is believed to exert its analgesic effect by inhibiting the re-uptake of norepinephrine and serotonin. There are several published cases of tramadol's involvement in drug-related deaths and impairment. Reports of deaths involving tramadol alone with associated tissue concentrations are rare. This report documents a case in which tramadol overdose was identified as the cause of death. The following tramadol concentrations were found in various tissues: blood, 20 mg/L; urine, 110.2 mg/L; liver, 68.9 mg/kg; and kidney, 37.5 mg/kg. Tissue distributions of the two primary metabolites, N-desmethyl and O-desmethyl tramadol, are also reported. In each tissue or fluid except urine, the tramadol concentration was greater than either metabolite, consistent with other reports of drug-impaired drivers and postmortem cases. The O-desmethyl metabolite concentration was greater than the N-desmethyl metabolite concentration in all tissues; this is in contrast to other postmortem reports, in which the majority of cases report concentrations of O-desmethyl as less than those of N-desmethyl. This may be useful as an indicator of time lapse between ingestion and death.

Adult↗

PubMed1994

Tissue distribution of human acetylcholinesterase and butyrylcholinesterase messenger RNA.

Cholinesterase inhibitors occur naturally in the calabar bean (eserine), green potatoes (solanine), insect-resistant crab apples, the coca plant (cocaine) and snake venom (fasciculin). There are also synthetic cholinesterase inhibitors, for example man-made insecticides. These inhibitors inactivate acetylcholinesterase and butyrylcholinesterase as well as other targets. From a study of the tissue distribution of acetylcholinesterase and butyrylcholinesterase mRNA by Northern blot analysis, we have found the highest levels of butyrylcholinesterase mRNA in the liver and lungs, tissues known as the principal detoxication sites of the human body. These results indicate that butyrylcholinesterase may be a first line of defense against poisons that are eaten or inhaled.

Acetylcholinesterase↗

PubMed1994

Pharmacokinetics and tissue distribution of recombinant human transforming growth factor beta 1 after topical and intravenous administration in male rats.

Recombinant human transforming growth factor beta (rhTGF-beta 1) enhances the healing process after topical application to various animal wound models. A detailed pharmacokinetic and tissue distribution study was performed to support the clinical development of rhTGF-beta 1 for wound healing indications. Rats received radioiodinated or unlabeled rhTGF-beta 1 as an intravenous (iv) bolus or as a topical formulation applied to a full thickness wound. Plasma concentrations of TGF-beta 1 were estimated from TCA-precipitable radioactivity or were measured by ELISA. Following iv administration, the initial half-life was rapid (< 11 min), regardless of whether radiolabeled or unlabeled rhTGF-beta 1 was used. The terminal half-life was long (163 min) when the test material was radioiodinated and administered as a trace dose and relatively short (< or = 61 min) when given at high doses and assayed by ELISA. Analysis of plasma radioactivity by SDS-PAGE revealed a time-dependent clearance of the 25-kDa parent molecule without a significant appearance of lower molecular weight radiolabeled metabolites. The majority of the radioactivity was associated with highly perfused organs, known iodide elimination pathways, and the thyroid at 1 and 8 hr after iv injection. After topical administration of a high dose (0.8 mg/kg), no immunoreactive TGF-beta 1 was detectable in plasma samples taken over a 48-hr period. However, trace amounts (< or = 0.05 ng/mL) of acid-precipitable radioactivity were detected in plasma after topical application of [125I]rhTGF-beta 1 (1 microgram/kg, 126 microCi/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗

PubMed2000

Human brain GABA transaminase tissue distribution and molecular expression.

Human brain gamma-aminobutyrate transaminase is differentially expressed in a tissue-specific manner. mRNA master dot-blot analysis for 50 different human tissues, including different brain regions and fetal tissues, provided a complete map of the tissue distribution. Genomic Southern analysis revealed that the gamma-aminobutyrate transaminase gene is a single copy, at least 15 kb in size. In addition, human brain gamma-aminobutyrate transaminase cDNA was expressed in Escherichia coli using a pGEX expression vector system. Catalytically active gamma-aminobutyrate transaminase was expressed in large quantities and the purified recombinant enzyme had kinetic parameters that were indistinguishable from those isolated from other mammalian brains. The human enzyme was inactivated by a well-known antiepileptic drug vigabatrin. Values of Ki and kinact were 1 mM and 0.35 min-1, respectively. Results from inactivation kinetics suggested that human gamma-aminobutyrate transaminase is more sensitive to the vigabatrin drug than the enzyme isolated from bovine brain.

4-Aminobutyrate Transaminase↗

PubMed2006

Amphotericin B tissue distribution in autopsy material after treatment with liposomal amphotericin B and amphotericin B colloidal dispersion.

OBJECTIVES: Tissue concentrations of amphotericin B were determined in autopsy material of patients who had been treated with liposomal amphotericin B or amphotericin B colloidal dispersion (colloidal amphotericin B) for suspected or proven invasive fungal infection. PATIENTS AND METHODS: Amphotericin B tissue levels were measured in liver, spleen, lung, kidney, and myocardial and brain tissue of 20 patients who had been treated with lipid-formulated amphotericin B, before they died from multi-organ failure. Seven patients had been treated with liposomal amphotericin B (AmBisome) and thirteen with colloidal amphotericin B (Amphocil). Tissue samples were obtained during routine autopsy, homogenized and extracted with methanol. Amphotericin B concentrations were measured using HPLC after purification by solid phase extraction. RESULTS: The highest amphotericin B levels were found in liver and spleen, followed by kidney, lung, myocardium and brain. In the lung higher amphotericin B concentrations were found after treatment with amphotericin B colloidal dispersion than after therapy with liposomal amphotericin B. CONCLUSIONS: The choice of lipid formulation may influence amphotericin B penetration into the lung.

Adult↗

PubMed2004

Brain- and heart-type fatty acid-binding proteins in the brain: tissue distribution and clinical utility.

BACKGROUND: Detection of brain injury by serum markers is not a standard procedure in clinical practice, although several proteins, such as S100B, neuron-specific enolase (NSE), myelin basic protein, and glial fibrillary acidic protein, show promising results. We investigated the tissue distribution of brain- and heart-type fatty acid-binding proteins (B-FABP and H-FABP) in segments of the human brain and the potential of either protein to serve as plasma marker for diagnosis of brain injury. METHODS: B-FABP and H-FABP were measured immunochemically in autopsy samples of the brain (n = 6) and in serum samples from (a) patients with mild traumatic brain injury (MTBI; n = 130) and (b) depressed patients undergoing bilateral electroconvulsive therapy (ECT; n = 14). The protein markers S100B and NSE were measured for comparison. Reference values of B-FABP and H-FABP were established in healthy individuals (n = 92). RESULTS: The frontal, temporal, and occipital lobes, the striatum, the pons, and the cerebellum had different tissue concentrations of B-FABP and of H-FABP. B-FABP ranged from 0.8 microg/g wet weight in striatum tissue to 3.1 microg/g in frontal lobe. H-FABP was markedly higher, ranging from 16.2 microg/g wet weight in cerebellum tissue to 39.5 microg/g in pons. No B-FABP was detected in serum from healthy donors. H-FABP serum reference value was 6 microg/L. In the MTBI study, serum B-FABP was increased in 68% and H-FABP in 70% of patients compared with S100B (increased in 45%) and NSE (increased in 51% of patients). In ECT, serum B-FABP was increased in 6% of all samples (2 of 14 patients), whereas H-FABP was above its upper reference limit (6 microg/L) in 17% of all samples (8 of 14 patients), and S100B was above its upper reference limit (0.3 microg/L) in 0.4% of all samples. CONCLUSIONS: B-FABP and H-FABP patterns differ among brain tissues, with the highest concentrations in the frontal lobe and pons, respectively. However, in each part of the brain, the H-FABP concentration was at least 10 times higher than that of B-FABP. Patient studies indicate that B-FABP and H-FABP are more sensitive markers for minor brain injury than the currently used markers S100B and NSE.

Adult↗

PubMed2004

Tissue distribution of bovine spongiform encephalopathy agent in primates after intravenous or oral infection.

BACKGROUND: The disease-associated form of prion protein (PrP(res)) has been noted in lymphoreticular tissues in patients with variant Creutzfeldt-Jakob disease (vCJD). Thus, the disease could be transmitted iatrogenically by surgery or use of blood products. We aimed to assess transmissibility of the bovine spongiform encephalopathy (BSE) agent to primates by the intravenous route and study its tissue distribution compared with infection by the oral route. METHODS: Cynomolgus macaques were infected either intravenously or orally with brain homogenates from first-passage animals with BSE. They were clinically monitored for occurrence of neurological signs and killed humanely at the terminal stage of the disease. Brain, lymphoreticular tissues, digestive tract, and peripheral nerves were obtained and analysed by sandwich ELISA and immunohistochemistry for quantitative and qualitative assessment of their PrP(res) content. FINDINGS: Incubation periods after intravenous transmission of BSE were much shorter than after oral infection. We noted that PrP(res) was present in lymphoreticular tissues such as spleen and tonsils and in the entire gut from the duodenum to the rectum. In the gut, PrP(res) was present in Peyer's patches and in the enteric nervous system and nerve fibres of intestinal mucosa. Furthermore, PrP(res) was found in locomotor peripheral nerves and the autonomic nervous system. Amount of PrP(res) ranged from 0.02% to more than 10% of that recorded in brain. Distribution of PrP(res) was similar in animals infected by the intravenous or oral route. INTERPRETATION: Our findings suggest that the possible risk of vCJD linked to endoscopic procedures might be currently underestimated. Human iatrogenic vCJD cases infected intravenously raise the same public-health concerns as primary cases and need the same precautionary measures with respect to blood and tissue donations and surgical procedures.

Administration, Oral↗

PubMed2001

Pharmacokinetics of NS-49, a phenethylamine class alpha 1A-adrenoceptor agonist. 4th communication: tissue distribution, placental transfer and milk secretion of radioactivity in rats after a single oral administration of 14C-NS-49, and effects of repeated administration on its pharmacokinetics.

The tissue distribution, placental transfer and milk secretion of 14C-NS-49 ((R)-(-)-3'-(2-amino-1-hydroxyethyl)-4'-fluoro-methanesulfonanilide hydrochloride, CAS 137431-04-0), a phenethylamine class alpha 1A-adrenoceptor agonist, have been studied after a single oral administration (1 mg/kg) of a suspension formulation to rats. Radioactivity concentrations in tissues were generally highest 1 or 4 h, and for most tissues, exceeded those in the corresponding plasma. Concentrations were generally similar in male and female rats and persisted for at least 24 h. Radioactivity concentrations in most tissues declined in parallel with those in plasma. Placental transfer of radioactivity was low accounting for < 0.1% of the maternal dose. In milk, concentrations were of a similar order to those in the plasma but reached a peak later: the data implied that 14C-NS-49 readily diffused from the plasma into the milk. The absorption, distribution and excretion of 14C-NS-49 have been studied after the repeated administration (1 mg/kg) of a suspension formulation to rats for up to 21 days. At 21 days, radioactivity concentrations in plasma reached a peak 1 h and declined with a terminal half-life of 67 h. Steady state concentrations were reached during 14 days. Peak concentrations in tissues occurred 1 h and, in most tissues exceeded the plasma value. Radioactivity concentrations in tissues appeared to reach steady state during the 21-day dosing period. Tissue and blood cell concentrations declined more slowly than those in the plasma. Radioactivity excretion was relatively constant during the repeated administration and similar in urine (mean 45.8% total dose) and feces (mean 48.2% total dose). At 7 days after the last of 21 daily oral doses, only 0.2% of the total dose remained in the body, indicating that there is no marked accumulation of radioactivity in the tissues. The results obtained in these studies indicated that rats receiving NS-49 at 24 h intervals during chronic and reproductive toxicity studies would be continually exposed to the parent compound and/or its metabolites.

Adrenergic alpha-1 Receptor Agonists↗

PubMedDate not supplied

Excretion and tissue distribution of selenium following treatment of male F344 rats with benzylselenocyanate or sodium selenite.

Benzylselenocyanate (BSC), a synthetic organoselenium compound less toxic than sodium selenite (Na2SeO3), has been demonstrated to inhibit the development of neoplasia in several experimental animal models. We examined the excretion and tissue distribution of total Se after acute administration of BSC compared to Na2SeO3. Male F344 rats were treated po with approximately one-tenth of the LD50 values, our estimate of highest non-toxic dose. The doses administered were 9.85 mg/kg in the case of BSC and 4.35 mg/kg in the case of Na2SeO3. The rats were sacrificed at 1, 6, 24, 72, or 120 hr to obtain biological samples. The levels of total Se were determined by graphite furnace atomic absorption spectrophotometry following microwave digestion. In serum, the highest Se level was observed at 6 hr after administration of either BSC or Na2SeO3: 1.34 +/- 0.07 (mean +/- SE), or 2.09 +/- 0.11 micrograms/ml of serum, respectively. In urine and feces, the cumulative percentages of doses excreted within 3 days of BSC or Na2SeO3 treatment were, respectively, as follows: 11.36 +/- 0.82% and 18.33 +/- 0.77% in urine; and 6.67 +/- 0.66% and 31.14 +/- 4.66% in feces. Among the tissues of BSC-treated rats, the kidneys were found to have the highest Se levels throughout the experimental period (as much as 29 micrograms/g of tissue at 72 hr), followed by liver, small intestine, large intestine, lung, pancreas, heart, and spleen. The results indicate that Se from BSC-treated animals is excreted very slowly and is retained in the organs for a much longer period compared to rats treated with Na2SeO3. Whether the slow excretion and prolonged retention of BSC and/or its metabolites play a role in its chemopreventive action is currently under investigation.

Administration, Oral↗