Response to 'Ramipril attenuates lipid peroxidation and cardiac fibrosis in an experimental model of rheumatoid arthritis' - authors' reply

We thank Wang and colleagues for their comments [1] about our recent study [2] and would like to make two points to clarify our reasoning.

First, in our study [2], female Lewis rats have been used in order to induce arthritis. This experimental model of arthritis was well described in our previous study published in Molecular Therapy [3]. Actually, a number of researchers use male or female animals to induce arthritis. For example, the use of female rats to induce arthritis has been reported in several recent articles [4–11]. In our unpublished data, we have shown that (a) adjuvant most likely induces arthritis equally in female and male Lewis rats and (b) female and male Lewis rats with arthritis have similar levels of lipid peroxidation products and cardiac fibrosis markers in heart tissues. These data were obtained by using a small cohort of male Lewis rats (n = 3), and we are keeping in mind that additional experiments will be performed in a future project of ours with a large cohort of male rats.

Second, in our recent study [2], female Lewis rats with arthritis received ramipril (10 mg/kg per day). The dose of this drug was chosen from the literature [12–14].