Histomorphological changes of surri mouse thyroid gland following long term administration of morphine

There are contradictory reports about the effects of morphine on thyroid glands. The aim of the present study was to investigate the effects of long term use of morphine on the body weight، thyroid glands’ weight and the histomorphological structure of mouse thyroid gland at different stage of growth. In this experimental study 150 two weeks female bulb/c mice were randomly divided into three equal groups. The mice in each group were divided into 4 subgroups، subsequently. Subgroup one (control group; n=5) accessed to clean water. Subgroup two (sham group; n=5) received 5mg/ml sugar، orally. 0. 04mg/ml morphine and 5mg/ml sugar were available for subgroup three (experimental group one; n=20). 0. 4mg/ml morphine and 5mg/ml sugar were given orally to subgroup four (experimental group two; n=20). The first and second group received morphine for 21 days and the third group received morphine for 63 days. Results of investigating the mice and their thyroid glands weight were analyzed using ANOVA and Tukey tests، results of the histomorphological studies were reported as a descriptive report. The results showed that chronic use of morphine with both doses significantly reduce body weight of mice in group two and group three (P<0. 05). Moreover، chronic usage of morphine with both doses significantly reduced thyroid weight in group one and two (P<0. 05). Histomorphological studies revealed that chronic usage of morphine increased the size and shape of follicular cells in thyroid gland. Furthermore، the shape of follicles of thyroid gland in experimental groups were changed and contained a little clouid compared to control and sham groups. Based on the results from present study it can be concluded that the chronic usage of morphine may in addition of its effect on the body weight and thyroid gland weight have influence on the structure and function of thyroid gland.