Gene expression of kinin receptors B1 and B2 in PBMC from patients with cardiac syndrome X.

Introduction. Cardiac syndrome X (CSX) is defined by typical chest pain, ST segment depression on ECG and normal coronary angiography. Pathology of CSX may involve microvascular dysfunction related to inflammation and abnormal pain sensitivity. Kinins are labile peptides participating in vasodilation, inflammation and pain. Their effects are mediated by two receptors: B1 and B2. The aim of the study was to assess gene expression of kinin receptors in peripheral blood mononuclear cells (PBMC) from patients with CSX. Methods. The study was carried out in 34 patients with cardiac syndrome X, 13 with unstable angina and ten healthy subjects. Total mRNA was extracted from PBMC and the number of mRNA copies was assessed by quantitive reverse transcriptase polymerase chain reaction. Results and Conclusion. The study showed 7-fold higher transcriptional activity of B1R in CSX vs. control and 3.5 higher vs. UA. B2R expression was 2.5-fold higher in CSX group vs. control and UA, while in the letter two groups it was similar. Such disturbance in kinin signaling may participate in local vasoconstriction and may reflect disturbances in kinin signaling leading to nociceptive disturbances in these patients.