The Placenta as the Main Source of Serotonin in Ontogenetic Dynamics: Inflammation-Induced Modulation of Placental Serotonin Can Be Prevented by Immunoglobulin Administration

Placental serotonin is recognized as a key component of feto-placental physiology and can be influenced by environmental factors such as maternal diet, drugs, stress, and immune activation. In this study, we compared the contribution of placental and fetal sources to the maintenance of serotonin levels required for normal fetal development during ontogenetic dynamics. Our results demonstrated the leading role of the placenta at almost all stages of development. We investigated the modulatory effect of inflammation on placental serotonin levels. The data obtained showed that the susceptibility to prenatal inflammation depends on its severity and varies considerably at different stages of development. According to our results, inflammation-induced modulation of placental serotonin levels can be prevented by immunoglobulin administration at both early and late stages of development. Disturbances in placental serotonin signaling during critical developmental periods may have long-lasting consequences for the health and behavior of the offspring. Therefore, the ability to prevent environmental modulation of placental serotonin, and hence negative effects on the developing fetus, is of great importance.