Multiplexed immunoassays for simultaneous quantification of cardiovascular biomarkers in the model of H(G)-nitro-L-arginine methylester (L-NAME) hypertensive rat.

The multimarker approach using Luminex technology represents a new tool for studying the pathogenesis of cardiovascular disease. Although many cardiac biomarkers in heart failure have been well established, the role and significance of their measurement in hypertensive patients is still questionable. The aim of our study was to evaluate the relationship of selected biomarkers in L-NAME-induced hypertension to the left ventricular remodeling in the two different periods of hypertension development. Four groups of 3-month-old male Wistar rats were investigated: (1) control 4 (placebo for 4 weeks), (2) control 7 (placebo for 7 weeks), (3) L-NAME 4 (40 mg/kg/day for 4 weeks), and (4) L-NAME 7 (40 mg/kg/day for 7 weeks). BNP, cTnI, TNF-α, and VEGF were measured using Rat CVD Panel 1 Kit (Milliplex® MAP). Cardiac troponin T was determined using Elecsys® Troponin T high sensitive immunoassay (Roche, Switzerland). Although the systolic blood pressure increases about 50% in L-NAME-induced hypertension in rat, both hypertrophy and fibrosis were expressed only slightly in this experiment. The levels of BNP, TNF-α, or VEGF did not differ significantly among groups. However, cardiac troponin T measured by high sensitive ELISA was significantly (P<0.05) increased in L-NAME 4 (0.229 μg/l versus 0.034 μg/l) and L-NAME-7 groups (0.366 μg/l versus 0.06 μg/l) in comparison with the controls. We conclude that the slightly increased cTnT levels could indicate ischemic damage of L-NAME-hypertensive heart. Importantly, to our best knowledge, this is the first study indicating that CVD rat panel may be a useful methodological tool in experimental cardiology.