Serotonin and cyclic sleep organization in healthy full-term newborns

Abstract

Relevance: The growth of neuropsychiatric diseases caused by perinatal pathology indicates the need to study the biochemical markers of brain damage in the newborn for the timely prevention of adverse consequences. Serotonin in early ontogenesis provides intensive development of neuronal structures and cortical networks involved in the mechanisms of formation of cyclic sleep organization a fine criterion of morphofunctional development of the brain.
 aim: The aim of the work is to study the content of serotonin in healthy full-term newborns in comparison with the quantitative and qualitative characteristics of the electropoligraphic sleep pattern.
 Material and methods: 84 healthy newborns were examined, which, depending on the gestational age, were divided into 3 groups: I 37 weeks (20 people), II 38 weeks (24 people), III 39-40 weeks (40 people). The content of serotonin in platelet-rich plasma of blood from the umbilical cord vein and in platelet suspension prepared from venous blood taken from mothers and children on the first day of life and again on day 5 was determined by high-performance liquid chromatography with electrochemical detection. A quantitative and qualitative analysis of the sleep electropoligram was performed 7-12 hours after birth.
 Results: The content of serotonin in platelet-rich plasma in umbilical cord blood in children does not depend on the method of birth, is 2 times lower than in the venous blood of mothers (0.379 0.116 microns/l, versus 0.756 0.200 microns/l, but there is a high correlation between the indicators (r = 0.8, p 0.05). At the gestational age of 39-40 weeks, the level of serotonin in platelet-rich plasma and in venous blood platelets is significantly higher than in those born at 37 weeks. In the latter, the increase in the content of serotonin in platelets continues after birth (at day 1, 0.539 0.149 nM/109 Tr, and on day 5 0.846 0.094 nM/109 Tr; p 0.05), whereas the indicators for those born at 39-40 weeks of pregnancy. They do not change (0.797 0.190 nM/109 Tr and 0.749 0.142 nM/109 Tr, respectively). A significant increase in the content of serotonin in the platelet-rich plasma and in the platelets of the child in the period from 37 to 39 weeks, both during intrauterine development and in the first days of life, correlates with an increase in the representation of the orthodox phase in the sleep cycle.
 Conclusion: The general pattern of changes in serotonin content and cyclic sleep organization in the early neonatal period in healthy newborns, depending on gestational age, indicates the possibility of using the obtained standard values of serotonin as a biochemical marker of functional brain development.