The fate of N-methyl-N'-(hydroxymethyl)thiourea in the rat.
1. The fate of N-methyl-N'-(hydroxy[14C]methyl)thiourea (MHT) has been studied in the male Sprague-Dawley rat. The compound is degraded to N-methylthiourea and formaldehyde. 2. N-Methylthiourea is excreted as a urinary metabolite whereas the formaldehyde is not excreted, either in the urine or the expired air, but is metabolized via formate to CO2. 3. At least 50% of an i.p. dose (100 mg/kg) of MHT is excreted unchanged and some of this undergoes hydrolysis within the urine to N-methylthiourea and formaldehyde. Production of formaldehyde leads to the formation of the urinary artefact N-(hydroxymethyl)urea. 4. Tissue-distribution studies with 14C-MHT have shown that radioactivity is selectively associated with the thyroid gland. A preliminary investigation has indicated that MHT has anti-thyroid hormone activity as it lowers the thyroxine in rat serum.
D000818:Animals; D001826:Body Fluids / Q000032:analysis; D005557:Formaldehyde / Q000378:metabolism; D008297:Male; D009677:Noxythiolin / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013890:Thiourea / Q000031:analogs & derivatives* / Q000378:metabolism; D014018:Tissue Distribution
D005557:Formaldehyde; D009677:Noxythiolin; C002267:N-methylthiourea; D013890:Thiourea