Abstract: Male S-D rats were intravenously injected with mo Phine HCL in the dose of 12.5 mg/kg body weight,once and killed in 2h.after administration.Their tissue blocks of brain,liver,kidney,heart and lungs were taken and fixed in solution of 2% glutaraldehyde and 4% paraformaldehyde.Routine paraffin sections were prepared and stained by SABC immuno-histochemical techniques using rabbit antisera against morphine.The results showed that positive staining was seen in epithelial cells of the distal part of the renal tubules and of the collecting tubules in medulla renalis,hepatocytes around central veins, alveolar and bronchial epithelial cells of lungs, some nerve cells,glia cells and epithelial cells of the ependyma in the midbrain, cardiocytes as well as endothelial cells of the capillaries.sera and urine inthe renal tubules.

Key words: morphine, immunohistochemistry, intoxication, rat