Thyroxine-evoked decrease of jejunal lactase activity in adult rats.
Daily administration of L-thyroxine (20 micrograms or 200 micrograms/100 g body weight) to adult male rats decreased jejunal lactase activity by 35% after 2-, 3-, 4- and 10 days. Four days of injections of D-thyroxine (200 micrograms/100 g body weight/day) produced a similar decrease of lactase activity. Sucrase activity was uninfluenced except for a 30% increase after daily injections of L-thyroxine (200 micrograms/100 g body weight) for 10 days. Acid beta-galactosidase activity was unaffected by either D- or L-thyroxine.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D005696:Galactosidases / Q000378:metabolism*; D007279:Injections, Subcutaneous; D007421:Intestine, Small / Q000201:enzymology*; D007583:Jejunum / Q000201:enzymology; D008297:Male; D051381:Rats; D013393:Sucrase / Q000378:metabolism; D013974:Thyroxine / Q000008:administration & dosage / Q000494:pharmacology*
D005696:Galactosidases; D013393:Sucrase; D013974:Thyroxine