RESUMO
In the present work, rat liver tissue were incubated in different phosphatebuffer solution [pHs 4, 6, 7, 9 and 11] for different periods of times [2, 4and 12 hours]. Hematoxylin and eosin stained sections were studiedmicroscopically by oil immersion objective lens. The results showed that, atacidic PHs, the cells and their nuclei tend to shrink with relatively betterpreservation of structures and increased staining affinity even 12 hoursautolysis. At pH 11, the appearance of liver tissue was very deterioratedeven at 2 hours autolysis. At neutral PH, staining affinity of cells weremoderately low with less preservation of structure than at acidic ormoderately alkaline PHs. The study highly recommended the consideration ofunusual PH changes before any interpretation of antemortem or postmortemhistopathological changes or estimation of time of death. The study alsorecommended routine microscopic examination of liver tissue in autopsy cases, inwhom unusual PH deviation is expected such as some poisons or diabeticketoacidosis. In case of tissue fixation, whether by formalin orgluteraldehyde, it was recommended to adjust PH accurately to avoid artifactsdue to PH deviation