title: Action of dyes and indicators on rat-liver regeneration.
abstract: When various dyes and indicators were fed to partially hepatectomized male rats as supplements in a basal diet for 10 days after surgery, liver regeneration was stimulated by 1-phenylazo-2-naphthol and by 1-(p-phenylazophenylazo)-2-naphthol, as such or with methyl substituents on the phenyl rings, and also by cresyl violet, D & C Yellow No. 11 and methyl orange. The efficacy of the azonaphthols stemmed from the activity of the metabolic intermediate, 1-amino-2-naphthol, which was tested in rats at a level of 0.20% (as the hydrochloride). The presence of a nitro group or two methoxy groups on the phenyl ring of 1-phenylazo-2-naphthol or of sulphonic acid groups in either of the azonaphthol series led to compounds that were ineffective. The stimulants generally elicited liver enlargement when fed to intact rats for the same interval. In contrast to p-dimethylaminoazobenzene, which was ineffective at the level (0.20%) tested, the sulphonic acid derivative sodium p-dimethylaminoazobenzenesulphonate (methyl orange) was, as stated above, stimulatory. Differences in the molecular configuration of azo dyes are thus reflected in their action on regenerating liver. Sulphanilic acid, a prominent metabolite of several azo dyes, proved inactive in partially hepatectomized males at a level of 0.20%.
mesh_terms: D000818:Animals; D004396:Coloring Agents / Q000378:metabolism / Q000633:toxicity*; D006498:Hepatectomy; D007202:Indicators and Reagents / Q000633:toxicity*; D008115:Liver Regeneration / Q000187:drug effects*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D013329:Structure-Activity Relationship
chemical_list: D004396:Coloring Agents; D007202:Indicators and Reagents