Histological Changes Induced in Gonads, Liver and Kidney of Zebra Fish (Danio Rerio) Under the Effect Octylphenol (OP)

Abstract

World-wide researches during the last years are focused upon the negative effects caused by the natural chemical compounds and anthropogenic compounds, already being demonstrated that a great part of them change the endocrine control over reproduction at different species. The issue studied by our team is concerned with the histological changes that appear within liver, kidney and gonadal development at the zebra fish (Danio rerio), exposed to octylphenol from 21-115 days, and within 21-75 days of life. In order to achieve the histological preparations, for each period under study, fishes were divided into three groups of 30 individuals, namely: Lot 1 - Control, respectively lots 2 and 3, at which the administrated octylphenol concentrations were of 60 μg  L-1, respectively 100 μg  L-1. Fishes of the six groups were raised in 30-liters aquariums (30 fish / aquarium). Fragments of liver, kidney and gonads were processed histologically, colored with the Mallory thrichromic staining method and examined with the optical microscope. Histopathological study revealed changes in the three organs, namely this fine granulation hepatocytes, peritubular edema and vascular ectasia in renal parenchyma and their differentiation in the gonads to sex predominantly female, issues that demonstrate the estrogenic effect of the octylphenol. Those microscopical aspects observed in the kidney and liver of the specimens exposed to action of octhylphenol, suggest that the octhlyphenol is bind to the estrogenic receptors on the membrane of hepatic cells, inducing vitellogenin synthesis.