Developmental stages and energy restriction affect cellular oncogene expression in tissues of female rats.
The influence of developmental stages and energy restriction on c-Ha-ras and c-fos cellular oncogene mRNA level was examined in mammary tissue and liver of female rats. c-Ha-ras and c-fos RNA transcripts in mammary tissue peaked at 9 wk of age, decreased during pregnancy, were lowest at mid-lactation and then increased at 25 wk. c-Ha-ras in liver showed highest expression at 5 wk and was hardly detectable at 11 wk, mid-pregnancy, mid-lactation and 25 wk. Liver c-fos and c-Ha-ras mRNA levels were similar. Lower c-Ha-ras and c-fos mRNA levels were observed in mammary tissue of energy-restricted (to 70% of ad libitum intake) rats at 25 wk compared with those allowed ad libitum access to food. Energy restriction did not affect liver c-Ha-ras and c-fos mRNA levels throughout the experimental period. These results demonstrate that developmental stages and energy restriction affect cellular oncogene mRNA levels with tissue-specific patterns.
Baik
M
M
Department of Animal and Range Sciences, North Dakota State University, Fargo 58105.
Choi
C B
CB
Keller
W L
WL
Park
C S
CS
D000375:Aging / Q000502:physiology*; D000818:Animals; D002149:Energy Intake; D005260:Female; D015870:Gene Expression; D016762:Genes, fos / Q000235:genetics; D011905:Genes, ras / Q000235:genetics; D007774:Lactation / Q000502:physiology; D008099:Liver / Q000254:growth & development / Q000378:metabolism*; D008321:Mammary Glands, Animal / Q000254:growth & development / Q000378:metabolism*; D009857:Oncogenes / Q000235:genetics*; D009928:Organ Specificity; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D012333:RNA, Messenger