The alteration of asymmetric dimetilarginine (ADMA) levels in cardiac and gastrocnemius muscles following radioactive iodine application in guinea pigs and the effect of L-carnitine on this alteration

Abstract

Purpose: Tissue levels of asymmetric dimetilarginine (ADMA) and symmetric dimetilarginine (SDMA) were investigated in cardiac ventricle and gastrocnemius muscles of guinea pigs treated with radioactive iodine (RAI) alone or in combination with L-carnitine (LC).

Material and methods: Group 1 received no treatment (control group). Group 2 received a total dose of 30 mCi⁻¹kg⁻¹ body weight iodine-131 alone. Group 3 received 200 mg⁻¹kg⁻¹ of LC for 10 days alone. Group 4 received 200 mg⁻¹kg⁻¹ of LC plus RAI therapy. Free thyroid hormones, ADMA and SDMA concentrations were measured.

Results: Serum free thyroid hormone concentrations were found decreased in the RAI and LC-RAI groups after RAI application. A significant decrease in ADMA and SDMA concentration was observed in ventricle muscle following RAI application. The LC-RAI group had significantly decreased ADMA levels in ventricle muscle compared with those of the control group. Similarly, SDMA concentrations in ventricle and gastrocnemius muscles of the LC-RAI groups were significantly lower than those of the control groups.

Conclusions: Our results indicated that RAI appears to exert an inhibitory effect on ADMA and SDMA levels of ventricular muscle. LC administration when given adjuvant to RAI therapy may cause a marked decrease in ADMA concentrations of both ventricular and gastrocnemius muscles.

Keywords:

• asymmetric dimethylarginine
• hypothyroidism
• muscle
• radioactive iodine
• ventricle

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.