Chronic hypoxia-induced pulmonary hypertension in rat: the best animal model for studying pulmonary vasoconstriction and vascular medial hypertrophy

Abstract

Numerous animal models of pulmonary hypertension (PH) are currently used to evaluate new therapies; investigating both their efficacy and the mechanism of their effect. They are also used to explore the biochemical mechanisms at work, with a view of identifying new drug targets. The chronic hypoxia-induced PH rat model is among the most commonly used animal models of PH. It is well known that alveolar hypoxia causes constriction of resistance vessels in the pulmonary vascular bed and followed by medial hypertrophy and muscularization of pulmonary arterioles, leading to sustained elevation in pulmonary artery pressure (PAP). The combination of these physiologic and pathologic processes imposes a mechanical and obliterative impact on the pulmonary circulation which mimics the common clinical features of pulmonary arterial hypertension (PAH) in patients. Researchers have slowly unraveled various etiology components in initiating and modifying influences in the hypoxia-induced PH rat model and the accumulation of knowledge could improve future treatments of PAH. This review examines the strengths and limitations of the chronic hypoxia-induced rat PH model and its value in the assessment of new treatments for PH.