Colchicine attenuates left ventricular hypertrophy but preserves cardiac function of aortic-constricted rats

To investigate the effects of colchicine on left ventricular (LV) function and hypertrophy (LVH) of rats subjected to constriction of transverse aorta (TAoC), we evaluated SO (sham operated, vehicle; n = 25), SO-T (sham operated, colchicine 0.4 mg/kg body wt ip daily; n = 38), TAoC (vehicle; n = 37), and TAoC-T (TAoC, colchicine; n = 34) on the 2nd, 6th, and 15th day after surgery. Colchicine attenuated LVH of TAoC-T compared with TAoC rats, as evaluated by ratio between LV mass (LV(M)) and right ventricular mass, LV wall thickness, and average diameter of cardiac myocytes. Systolic gradient across TAoC ( approximately 45 mmHg), LV systolic pressure, LV end-diastolic pressure, and rate of LV pressure increase (+dP/dt) were comparable in TAoC-T and TAoC rats. However, the baseline and increases of LV systolic pressure-to-LV(M) and +dP/dt-to-LV(M) ratios induced by phenylephrine infusion were greater in TAoC-T and SO-T compared with SO rats. Baseline and increases of +dP/dt-to-LV(M) ratio were reduced in TAoC compared with SO rats. TAoC rats increased polymerized fraction of tubulin compared with SO, SO-T, and TAoC-T rats. Our results indicate that colchicine treatment reduced LVH to pressure overload but preserved LV function.