Comparison of the effect of various doses of thyroxine on jejunal disaccharidases in intact and adrenalectomized rats during the first 3 weeks of life.
Administration of D,L-thyroxine (T4) daily (25 or 250 nmol/100 g body weight/24 h) for 4 days increased jejunal activity in 15-day-old rats; no effect was seen in 8-day-old rats. Maltase activity was increased in 15-day-old rats only when a 250-nmol dose was used. Similar results were obtained in unoperated and adrenalectomized rats. Specific activity of lactase was not influenced in unoperated 8- and 15-day-old rats; it was decreased in adrenalectomized 8- and 15-day-old rats when treated with a 250-nmol dose of T4; in 15-day-old rats, it also responded to 25-nmol doses. The lowest dose used (2.5 nmol/100 g body weight) had no effect at all.
D000315:Adrenalectomy; D000375:Aging; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D004186:Disaccharidases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D066298:In Vitro Techniques; D007583:Jejunum / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051381:Rats; D013974:Thyroxine / Q000494:pharmacology*; D001616:beta-Galactosidase / Q000378:metabolism
D004186:Disaccharidases; D001616:beta-Galactosidase; D013974:Thyroxine