The effect of triiodothyronine on rat apolipoprotein A-I and A-IV gene transcription.
The effects of triiodothyronine administration on the mRNA levels of apolipoprotein (apo)A-I, apo A-IV and albumin were determined in extracts of rat liver by hybridization to specific cDNA. The mRNA levels for apo A-I and apo A-IV in the rat liver increased to 347% and 143% of normal, respectively, following a single injection of triiodothyronine (50 microgram/100g body weight). Under the same conditions there was no significant change in the hepatic mRNA level for albumin. The rates of transcription of these genes were measured in isolated hepatic nuclei prepared from hypothyroid and hyperthyroid rats. The rate of transcription of the albumin gene did not change significantly in either thyroid state. The rate of transcription of the apo A-I and apo A-IV genes increased in the hyperthyroid state to 342% and 202% of normal respectively, and decreased in the hypothyroid state to 26% and 44% of normal respectively.
D000818:Animals; D016632:Apolipoprotein A-I; D001054:Apolipoproteins A / Q000235:genetics*; D005796:Genes / Q000187:drug effects*; D006980:Hyperthyroidism / Q000378:metabolism; D007037:Hypothyroidism / Q000378:metabolism; D008075:Lipoproteins, HDL / Q000235:genetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D011915:Rats, Inbred BUF; D012016:Reference Values; D014158:Transcription, Genetic / Q000187:drug effects*; D014284:Triiodothyronine / Q000494:pharmacology*
D016632:Apolipoprotein A-I; D001054:Apolipoproteins A; D008075:Lipoproteins, HDL; D012333:RNA, Messenger; C022205:apolipoprotein A-IV; D014284:Triiodothyronine