Abstract
Pulmonary hypertension (PH) is a multifactorial disease characterized by an average pulmonary artery pressure of 25mmHg or higher. Although PH is generally classified into five distinct groups, pulmonary arterial hypertension (PAH), especially the idiopathic subgroup (IPAH) or congenital heart disease (CHD) subgroup, has been the focus of most of our research from a serotonergic regulatory perspective. There are many models of pulmonary hypertension in experimental practice. Each model aim at certain goals and is based on various mechanisms. The monocrotaline model of pulmonary hypertension is one of the best models for studying pulmonary hypertension due to endothelial dysfunction. However, in experimental practice, this model is used only for adulthood. At present, the influence of the serotonergic system is not taken into account in the treatment of children with pulmonary hypertension. We have modified the monocrotaline model of pulmonary hypertension for immature rats. A positive correlation was found between the concentration of serotonin metabolites in the urine and the degree of pulmonary hypertension, which can become a potential marker of pulmonary hypertension.