title: Cellular analysis of c-Ha-ras gene expression in rat liver after CCl4 administration.
abstract: Expression of the c-Ha-ras proto-oncogene is specifically enhanced during liver regeneration, in parallel with increased DNA replication, which suggests that c-Ha-ras may play a role in the control of regeneration. In this study, an in situ hybridization technique was applied for analysis of expression of the c-Ha-ras gene at the cellular level during liver regeneration induced by CCl4 administration. The in situ hybridization was compared with the observation for the p21c-Ha-ras protein, the corresponding protein of the c-Ha-ras gene, by immunohistochemistry. In normal rat liver, a few hepatocytes expressed the mRNAs and the corresponding proteins without any preferential localization. Zonal heterogeneity of c-Ha-ras gene expression first became evident at 12 hr after CCl4 administration, a higher number of gene products being detected in the pericentral zone than in the periportal zone. This heterogeneity became maximal at 24 hr after CCl4 administration. Zonal heterogeneity in the level of the p21c-Ha-ras protein paralleled that in the level of gene expression. Furthermore, both hepatocytes and nonparenchymal cells participated in expression of the c-Ha-ras gene during liver regeneration.
authors.affiliation: First Department of Medicine, Osaka University Medical School, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sasaki
authors.forename: N
authors.initials: N
authors.lastname: Hayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Morita
authors.forename: T
authors.initials: T
authors.lastname: Ito
authors.forename: A
authors.initials: A
authors.lastname: Kasahara
authors.forename: H
authors.initials: H
authors.lastname: Fusamoto
authors.forename: N
authors.initials: N
authors.lastname: Sato
authors.forename: M
authors.initials: M
authors.lastname: Tohyama
authors.forename: T
authors.initials: T
authors.lastname: Kamada
mesh_terms: D000818:Animals; D002252:Carbon Tetrachloride Poisoning / Q000378:metabolism* / Q000473:pathology; D007124:Immunoenzyme Techniques; D008099:Liver / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D008115:Liver Regeneration / Q000187:drug effects; D008297:Male; D009693:Nucleic Acid Hybridization; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis* / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras); D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D016283:Proto-Oncogene Proteins p21(ras)