The role of serotonergic system in cardiovascular diseases development in children

Abstract

The role of the serotonin system as a link in the pathogenesis of atherosclerosis and arterial hypertension is widely discussed during the recent decades. Serotonin and histamine are part of humoral system of physiological processes regulators and modulators which under pathological conditions are transformed into factors contributing to the disease development. The membrane serotonin transporter has been identified on neurons, platelets, myocardium and smooth muscle cells. The higher is the activity of membrane transporter, the higher is the platelet serotonin concentration, its release into the blood plasma increases thus implementing its negative effects on platelets and wall of the vessels. 5-HT1A, 5-HT2 and 5-HT3 receptor subtypes play a key role in the central mechanisms of regulation of cardiovascular activities while peripheral effects of serotonin on the vascular system are mediated by 5-HT1, 5-HT2, 5-HT3, 5-HT4 and 5-HT7 receptor subtypes. Activation of 5-HT1A receptors causes inhibition of central sympathetic influences and further bradycardia, while 5-HT2 receptors activation - arousal of the sympathetic division, blood pressure elevation, and tachycardia. With the development of anaerobic processes serotonin via 5-HT2 receptors triggers apoptosis of cardiomyocytes leading to the development and progression of heart failure. Participation of 5HT2B receptors in the regulation of heart development during embryogenesis was shown on the mutant mice: cardiomyopathy with ventricular mass loss due to reduction of cardiomyocytes number and size was revealed. The involvement of 5-HT4 receptors in the development of sinus tachycardia and atrial fibrillation; in turn, the use of 5-HT4 receptor antagonists proved to be effective in the treatment of this kind of arrhythmias. Therefore, the study of the serotonergic system role in the development of cardiovascular diseases will allow to open new links in the pathogenesis of arterial hypertension in childhood.