ANÁLISE HISTOLÓGICA, HISTOQUÍMICA E ULTRAESTRUTURAL DA MUSCULATURA DORSAL E VENTRAL DO GUARU (Poecilia vivipara BLOCHI & SCHNEIDER, 1801)

Poecilia vivipara (guaru), a neotropical, small, euryhalinefish, has been being used as a biomonitor. Dorsal and ventralmuscles of Poecilia vivipara were analyzed to standardize methodologiesfor evaluating the normal tissue structure, in order to usethem in toxicity studies. Thus, chemical and physical fixations werecarried out, aiming at the histological and histochemical proceduresof staining and reaction. The methods HE and MT revealed theorganization of SSMF with epiaxial and hypaxial muscle bundlesand associated conjunctive. MA marked the SSMF and facilitatedthe observation of sarcomeres in the presence of a thin metacromaticallystained band. Part of the SSMF was positive PAS andreactive amylase, indicating the distribution of glycogen withinthe fibers. In the presence of SBB the fibers were reactive mainlyin the dorsal region, indicating the presence of lipids. Cells withmitochondrial enzyme-rich cytoplasm were found in SDH pH 10.5.The SSMF stained with AT were arranged in alternating transversebands, which correspond to the pattern seen under the MET. The useof these methodologies allowed the indication of Poecilia viviparamuscles as a tool for environmental variations studies, because itsnormal structure is standard in teleosts.