Background: Amiodarone is a highly effective and class III antiarrhythmic drug. It can be used to treat wide range of arrhythmias. However, it is markedly concentrated in tissues leading to multiple adverse effects mainly on thyroid gland. The concomitant use of vitamin E with amiodarone in treatment of arrhythmias can ameliorate the hazardous effects of amiodarone on thyroid gland
Aim of work: The aim of this work is to study the histological and ultrastructural effects of amiodarone as antiarrhythmic drug on the thyroid gland, as well as the ability of vitamin E to protect against amiodarone induced thyroid damage.
Material and methods: Thirty adult male albino rats (weighing 150-200 g), were used in the study. Rats were divided into three groups (10 per group): Group A (Control group); Group B (Amiodarone treated group) and Group C (Amiodarone + Vitamin E treated group). Rats were sacrificed after 6 weeks of amiodarone administration. Thyroid gland was examined histologically and ultrastructurally.
Results: Histological and ultrastructure examination of thyroid glands of rats treated with amiodarone showed disorganized follicles. Follicular epithelium showed focal disruption and desquamation. The interfollicular tissue showed increased collagen deposition. Electron microscopic examination revealed irregular nuclei, dilated rough endoplasmic reticulum and swollen mitochondria. Concomitant administration of vitamin E showed marked amelioration of hazardous effects of amiodarone with improved histologic and ultrastructural signs
Conclusion: Amiodarone induces damage of the thyroid gland. Administration of vitamin E protects the thyroid gland and attenuates histopathological changes induced by amiodarone.