title: Induction of liver tumors in rats by sodium nitrite and methylguanidine.
abstract: The carcinogenicity of sodium nitrite and methylguanidine singly and together were examined in rats. A hepatocellular carcinoma, a hemangiosarcoma and a spindle cell sarcoma  were found in 3 of 15 rats fed continuously on pellet diet containing 0.16% sodium nitrite and 0.16% methylguanidine. Hemangiomas and bile duct adenomas of the liver were also found in 6 and 8, respectively, of the 15 rats in this group. Hemangiomas and bile ducts adenomas of the liver were found in 2 and 3, respectively, of the 4 rats fed on pellet diet containing 0.16% sodium nitrite. Only 1 of 5 rats fed on pellet diet containing 0.16% methylguanidine developed a hemangioma. No tumor was found in the control group. All the tumors were found in rats that survived for over 12 months. No significant changes were detected in the esophagus or stomach.
mesh_terms: D002759:Adenoma, Bile Duct / Q000139:chemically induced; D000818:Animals; D001650:Bile Duct Neoplasms / Q000139:chemically induced; D006146:Guanidines / Q000009:adverse effects*; D006391:Hemangioma / Q000139:chemically induced*; D006394:Hemangiosarcoma / Q000139:chemically induced; D008113:Liver Neoplasms / Q000139:chemically induced*; D008297:Male; D008760:Methylguanidine / Q000009:adverse effects*; D009374:Neoplasms, Experimental / Q000139:chemically induced*; D009573:Nitrites / Q000009:adverse effects*; D051381:Rats; D012509:Sarcoma / Q000139:chemically induced
chemical_list: D006146:Guanidines; D009573:Nitrites; D008760:Methylguanidine