IL1B and Right ventricular hypertrophy: Experimental evidence: In hypoxia-induced pulmonary hypertension and in the MCT model, data on IL-1β were found to diverge: in the MCT model, high levels of IL-1β were measured and, conversely, treatment with an IL-1β receptor antagonist reduced pulmonary hypertension and right ventricular hypertrophy, while no such findings were reported in the hypoxia mouse model[23].