title: 11Beta-hydroxysteroid dehydrogenase bioactivity is increased in the colon but not kidneys of rats given supplementary thyroxine.
abstract: The aim of this study was to investigate the effect of altered thyroid status on 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD type 1) and type 2 (11beta-HSD type 2) bioactivity in rat kidney and colon. Male Sprague-Dawley rats (250 g) were treated with either L-thyroxine (T4) or propylthiouracil (PTU) for 4 weeks. Blood were then analysed for serum thyroxine, sodium (Na+) and potassium (K+). The kidneys and colon were assayed for 11beta-HSD type 1 and 11beta-HSD type 2 bioactivity. In T4 treated rats the serum thyroxine was significantly elevated (p<0.05) whilst PTU decreased serum thyroxine significantly (p<0.001) compared to controls. Serum Na+ and K+ were within normal limits. There were no significant changes in 11beta-HSD type 1 bioactivity in both treatment groups compared to controls. However, the 11beta-HSD type 2 bioactivity in rats given thyroxine was significantly higher in the colon (p<0.003) compared to controls. We conclude that altered thyroid status had no effect on 11beta-HSD type 1 bioactivity but 11beta-HSD type 2 bioactivity was elevated in the colon of rats given supplementary thyroxine.
authors.affiliation: Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur. ruszy@medic.ukm.my
authors.forename: B H
authors.initials: BH
authors.lastname: Ruszymah
authors.forename: Z
authors.initials: Z
authors.lastname: Zaiton
authors.forename: S
authors.initials: S
authors.lastname: Aminuddin
authors.forename: B A
authors.initials: BA
authors.lastname: Khalid
mesh_terms: D042842:11-beta-Hydroxysteroid Dehydrogenases; D000818:Animals; D003106:Colon / Q000187:drug effects* / Q000201:enzymology*; D006913:Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D007668:Kidney / Q000187:drug effects* / Q000201:enzymology*; D008297:Male; D011441:Propylthiouracil / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013974:Thyroxine / Q000097:blood / Q000494:pharmacology*
chemical_list: D011441:Propylthiouracil; D006913:Hydroxysteroid Dehydrogenases; D042842:11-beta-Hydroxysteroid Dehydrogenases; D013974:Thyroxine