Immunohistochemical expression of activated caspase-3 in the parotid salivary glands of rats after long administration of Myristica fragrans

Twenty male Sprague-Dawley rats (200 ± 15 g) were used in the present work, they were divided into two main groups, the study group comprises fourteen animals and the control group comprises six animals. The control group animals were received 1ml of distilled water orallyon a daily basis for the duration of the experiment (8 weeks). The study groupweregiven 1ml of the prepared (Myristicafragrans)nutmeg aqueous extract orally on a daily basis in the following doses (100 and 500 mg/kg b.w.) for 8 weeks. The study group was subdivided into 2 subgroups (7 animals each) according to the dose which are 100 mg/kg b.w. group (Sub gp A) and 500 mg/kg b.w. group (Sub gp B) respectively.The parotid salivary glands were dissected from each rat and prepared for paraffin section.Sections for histological studiesstained with H&E and Masson’s trichrome stain, other sections were prepared for immunohistochemical study of activated caspase-3 expression. Histological results in Sub gp A showed intracellular cytoplasmic vacuoles of acinar cells, dilated ducts,lymphocytic infiltration, congested blood vessels and nuclear changes including hyperchromatism as well as pyknotic nuclei were observed. In addition, interacinar oedema was evident.In Sub gp B these changes were markedly severe. Immunohistochemical results revealed thatmost of the acinar and ductal epithelial cells of controlled group showed negative immunoexpression to caspase-3. Most of the nuclei and cytoplasm ofacinar and ductal cells of Sub gp A group revealed moderate positiveimmunoexpression to caspase-3.The reaction was more intense in Sub gpB .