Cytokines and cytokine receptors in fetal growth and development

The cytokine receptors for growth hormone (GH), prolactin and leptin have a critical role in regulating embryo, placental and/or fetal development, wh ich is dependent on stage of gestation and species. GH and prolactin recept ors are detectable from conception, and alterations in the maternal hormona l environment may impact on placental growth from this early stage of gesta tion. Leptin is critical for conception, but its role in fetal growth remai ns elusive. During late gestation, when fetal growth accelerates and organ maturation occurs, prolactin and insulin-like growth factor-I may have inte ractive roles in regulating the growth of specific tissues, including adipo se tissue. Prolactin, leptin and GH all have specific effects on fetal and neonatal energy balance, which are mediated in part through promoting lipol ysis and/or enhancing the expression of uncoupling proteins. An increased u nderstanding of these interactions is likely to have important implications for a number of potentially pathological conditions, including infection, obesity and hypertension.