Intestine monkeys

Metabolism. Absorption, distribution, metaboHsm, and excretion of thioglycolic acid have been reviewed (20). In summary,. -thioglycolic acid was absorbed significantly after appHcation to the skin of rabbits. After intravenous injection, the greatest counts of radioactivity were found in the kidneys, lungs, and spleen of monkey and in the small intestine and kidneys of rat. Most of the radioactivity was rapidly excreted in the urine in the form of inorganic sulfate and neutral sulfur. 

The ability of NB-355 to stimulate locomotor activity and induce dyskinesia in MPTP-treated squirrel monkeys was studied (MPTP induces parkinsonism) [9], NB-355 was similar to L-dopa in stimulating locomotor activity. Furthermore, NB-355 induced less severe dyskinesia than was seen with L-dopa. Some other prodrugs of L-dopa include short-chain alkyl esters (methyl, ethyl, isopropyl, butyl, hydroxypropyl, and hydroxybutyl) intended for rectal absorption [10], These esters of L-dopa have high water solubility (>600 mg/mL). Initial bioavailability studies indicated that all of these esters, with the exception of the hydroxypropyl ester, resulted in significantly greater bioavailability than that obtained with L-dopa itself. However, given the high level of esterase activity in the small intestine, the use of these compounds is limited to rectal administration. 

M Das, AN Radhakrishnan. Substrate specificity of a highly active dipeptidase purified from monkey small intestine. Biochem J 128 463-465, 1972. 

W Rubas, N Jezyk, GM Grass. Comparison of the permeability characteristics of a human colonic epithelial (Caco-2) cell line to colon of rabbit, monkey, and dog intestine and human drug absorption. Pharm Res 10 113-118, 1993. 

In 1941, Wald et al. reported that excreted xanthophylls were entirely of dietary origin and that only negligible amounts could originate from intestinal organisms (Wald et al. 1941, Wald 1945). Forty years later, this dietary origin was confirmed by results obtained in monkeys raised on a... 

K. P., Comparative studies of drug-metabolising enzymes in dog, monkey, and human small intestine, and in Caco-2 cells, Drug Metab. 

L. M., Hochman, J. H., Tran, L. O., Vyas, K. P., Comparative studies of drug metabolising enzymes in dog, monkey and human small intestines and in Caco-2 cells, Drug Metab. Disp. 1996, 24, 634-642. 

Studies on the fate of dopamine 4-sulfate (9.88) will serve to illustrate the reaction of deconjugation mentioned above. With this substrate, arylsulfatase activity in the dog was found to be highest in the kidney and liver, low in the intestine and heart, and almost nil in the brain and skeletal muscle [171]. Since this conjugate exists in high amounts in the plasma of humans, monkeys and dogs, the possibility was raised that it might be looked upon as a precursor or reservoir of free dopamine. 

Grass et al. [69] evaluated the performance of controlled release dosage forms of the anti-thrombic drug ticlopidine using computer simulations based on data from in vitro intestinal permeability studies in various sections of the intestine of rabbit and monkey. 

A half-life of 6 min for metabolism of di(2-ethylhexyl) adipate has been determined in rat small intestinal mucous membrane homogenates. The dominant urinary metabolite of di(2-ethylhexyl) adipate (500 mg/kg bw) in male Wistar rats is adipic acid, which accoimts for 20-30% of the administered oral dose. The other major metabolite which was found only in the stomach is mono(2-ethylhexyl) adipate (Takahashi et al., 1981). In cynomolgus monkeys, the glucuronide of mono(2-ethyl-hexyl) adipate and traces of unchanged di(2-ethylhexyl) adipate were foimd in the urine (BUA, 1996). 

Rozman KK, Rozman TA, Williams J, et al. 1982. Effect of mineral oil and/or cholestyramine in the diet on biliary and intestinal elimination of 2,4,5,2, 4, 5 -hexabromodiphenyl in the Rhesus monkey. J Toxicol Environ Health 9 611-618. 

Intestinal microorganisms readily hydrolyze chlorogenic acid to quinic and caffeic acids [13], Adamson et al. [14] have investigated the fate of [14C] labeled quinic acid in rats and monkeys. Total radioactivity has been measured in the urine, feces and expired air of rats. As a consequence, the excreted radioactivity is contained in the intact quinic... 

A deficiency of the vitamin can result in lymphopenia, convulsions, dermatitis, irritability, and nervous disorders in humans. A defidency in monkeys may cause arteriosclerosis, while in rats, acrodynia. Research indicates that all animals require vitamin Bg, Bacteria in intestines generate some of this vitamin, but relatively little is available to humans in this form. Endogenous sources are available to plants, fungi, and some bacteria. 

Radhakrishnan, A. N. 1977. Intestinal dipeptidases and dipeptide transport in the monkey and in man. In Peptide Transport and Hydroly i iba Foundation Symposium, -359. New York Elsevier Science Publishers. 

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