Letter to the Editor.

In order to calculated-measure the low-density lipoprotein cholesterol (LDL-C), the Friedewald formula is used. LDL can be calculated by Friedewald formula in this way: total cholesterol (TC) minus high-density lipoprotein (HDL)-cholesterol minus triglycerides (TG)/5 in milligrams per deciliter. In the article entitled "Agmatine protects rat liver from nicotine-induced hepatic damage via antioxidative, antiapoptotic, and antifibrotic pathways" published in the same journal (Vol, 389, pp. 1341-1351), LDL-C has been calculated in this way: LDL-C = TC - [HDL-C - (TG/5)] which is not in accordance with the Friedewald formula and thus the result is false. It may seem that this would be a typo but this could not be the case.