Induces cardiac myocyte hypertrophy in vitro. Binds to and activates the ILST/gp130 receptor. Expressed in the ventricle and atrium of adult rats. Also detected in the lung, kidney, liver, skeletal muscle, stomach and urinary bladder. Not detected in brain, colon, testis, spleen or thymus. Overexpressed in the ventricles in the case of hypertension and hypertrophy. Belongs to the IL-6 superfamily.