Precocious development of glucuronidating and hydroxylating enzymes in chick embryos treated with pituitary grafts.
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ABSTRACT:
SUBMITTER: Wishart GJ
PROVIDER: S-EPMC1172474 | biostudies-other | 1975 Nov
REPOSITORIES: biostudies-other
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Project description:1. Na(2) (35)SO(4), [1-(14)C]glucosamine and [1-(14)C]acetate were used as precursors of the sulphated glycosaminoglycans to study the biochemical effect of beta-aminopropionitrile in chick embryos. The incorporation of all three precursors was decreased in the treated embryos between days 7 and 10 of embryonic development. No inhibition of incorporation of these precursors occurred between days 16 and 20 of embryonic development at the dosages of beta-aminopropionitrile used. 2. beta-Aminopropionitrile treatment also decreased the amount of N-acetylhexosamines in the chick embryo and decreased the percentage of the hexosamine esterified by nucleotides. Respiration was decreased by homogenates prepared from treated embryos. Likewise, UDP-xylosyl- and UDP-galactosyl-transferase activities were decreased in treated embryos and cartilage from embryos and growing chicks. 3. The data suggest that beta-aminopropionitrile, in addition to the known lathyrogenic activity, either is or gives rise to a potent metabolic poison that interferes with basic cellular metabolism. The results are consistent with a decreased rate of ATP generation as an explanation for the decrease in glycosaminoglycan synthesis.
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