Peri-conceptual cytokine environment and consequences for human pregnancy

Abstract

Growth hormone, prolactin and placental lactogen are known as the growth- and lactogenic hormone (GLH; e.g., GH, PRL, and PL) family, which maintain adaptive immunity, including cell-mediated immunity, antibody, and autoimmune reactions, as well as maintain thymus and bone marrow functions. Insulin-like growth factor-1 participates in the regulatory action of growth hormone and prolactin. GLH shares signal transduction pathways with type I (γ-c) cytokines. This indicates a functional overlap. Dopamine is the hypothalamic regulator of PRL and GH secretion and the HPA axis. This action regulates healing and recovery from a disease. During acute illness, corticotrophic hormone (CRH) stimulates the HPA axis and vasopressin (VP) helps to maintain acute illness. The pituitary gland secretes adrenal cortex-stimulating hormone (ACTH) and the adrenal gland secretes glucocorticoids (GC) and catecholamines (CAT). When the disease subsides, VP not CRH will regulate chronic inflammation and recovery. VP also maintains adaptive immunocompetence during homeostasis because it stimulates the HPA axis and also prolactin. Oxytocin is immunoregulatory. Thyroidectomy in rats suppresses immune function and thyroxin releases growth hormone and prolactin from transplanted pituitary grafts in rats and also restores immune function. This indicates that thyroxin is an important immunoregulator. The growth hormone secretagogue, ghrelin, is immunoregulatory.