The antihistamine methapyrilene was examined for its ability to initiate hepatocarcinogenesis in rats. Rats were first subjected to partial hepatectomy and then were intubated with one of four doses (30, 100, 200 or 300 mg/kg) of methapyrilene hydrochloride (or an equivalent amount of water for controls, or 10 mg diethylnitrosamine/kg for positive controls). Rats were then fed 0.05% phenobarbital in the diet for 3, 6 or 9 months. The number and volume of altered hepatic foci were quantified with the histochemical markers gamma-glutamyl transpeptidase, glucose-6-phosphatase, and ATPase. The number of foci induced was increased 2- to 4-fold by the highest dose of methapyrilene at all 3 time points, but the only statistically significant increase was produced by the 200 mg/kg dose after 3 months of promotion. This study shows that methapyrilene may act as a weak initiator.
|Number of pages||6|
|State||Published - Aug 1989|
Bibliographical noteFunding Information:
We thank Dr. Harold Campbellf or his help in the use of the computert o quantifyf oci, and Wendy Kennan, Susan Moran, Jane Weeks, Mary Folz-Erbs, Susan Carlson, and Travis Lay for technical assistanceT. his work was supported by NIH grants ES07015, CA-071 75, CA-22484, CA-437 19, and contract ES-35024.
- enzyme altered foci
- rat liver
ASJC Scopus subject areas
- Cancer Research