[Potentially pre-neoplasics areas in rat's liver associated to chronic use of phenobarbital].
BACKGROUND
Phenobarbital has been used in experimental models because it is an important agent of carcinogenesis promotion in the liver of rats, and it is also non-genotoxic, organ-specific and dose-dependent.


OBJECTIVE
To evaluate the effects of the daily administration of phenobarbital in old rats treated with phenobarbital since their birth up to 24 months of age, in the absence of concomitant administration of chemical agents, which initiate carcinogenesis.


METHODS
A control group of male Wistar rats was fed with a basic diet and a second group was fed with the same basic diet added of 0.05% of phenobarbital, for a period of 24 months. Medium and right liver fragments were submitted to the histological processing and they were stained by hematoxiciline and eosin and were immunohystochemically colored to glutathione S-transferase placentary form.


RESULTS
Glutathione S-transferase placentary positive zones were detected in both groups and the images were analyzed concerning their number and surface extension through the technique of histometry analyses.


CONCLUSIONS
Chronic use of phenobarbital did not modify the number of glutathione S-transferase placentary form positive areas. Although, data indicates that glutathione S-transferase placentary form positive areas media size are increased, probably because there are an increase in their evolution capacity and irreversibility.
Silva
Helena Terezinha Hubert
HT
Fundação Faculdade Federal de Ciências Médicas de Porto Alegre, RS. hubertsilva@brturbo.com
Hartmann
Antonio Atalíbio
AA
D000818:Animals; D002273:Carcinogens / Q000008:administration & dosage / Q000494:pharmacology*; D005982:Glutathione Transferase / Q000378:metabolism*; D007150:Immunohistochemistry; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000201:enzymology* / Q000473:pathology; D008297:Male; D010634:Phenobarbital / Q000008:administration & dosage / Q000494:pharmacology*; D011230:Precancerous Conditions / Q000201:enzymology; D051381:Rats; D017208:Rats, Wistar
D002273:Carcinogens; D005982:Glutathione Transferase; D010634:Phenobarbital