title: Ontogenesis of the adrenal glucocorticoids and of the target function of the enzymatic tyrosine transaminase activity in the chick embryo.
abstract: Adrenal and plasma glucocorticoids were determined in developing chick embryos of Gallus domesticus from days 8 to 19 of incubation, using a competitive protein-binding assay. At the same time, tyrosine transaminase activity in the liver was studied as an adrenal-dependent target function. Total amounts of glucocorticoids in the adrenal gland increased from day 11 and reached 7 ng/pair of glands on day 19. This increase was related to growth of the adrenal since concentrations remained constant at about 380 pg/micrograms dry weight from days 9 to 18. Glucocorticoids appeared in the plasma on day 12 and their concentrations rose to 10 ng/ml on day 19, with a marked peak on day 13. This peak was not reflected in the tyrosine transaminase activity which appeared and developed independently of the variations in the circulating glucocorticoids.
mesh_terms: D000311:Adrenal Glands / Q000196:embryology* / Q000378:metabolism; D000818:Animals; D002642:Chick Embryo; D005938:Glucocorticoids / Q000096:biosynthesis* / Q000097:blood; D008099:Liver / Q000196:embryology / Q000201:enzymology; D009929:Organ Size; D014444:Tyrosine Transaminase / Q000378:metabolism*
chemical_list: D005938:Glucocorticoids; D014444:Tyrosine Transaminase