Influence of prolactin into immunity in stress

Popova E.V., Tinkov A.A., Nikonorov A.A., Popova Y.V., Karaulov A.V.

1 Orenburg State Medical University, Orenburg, Russia
2 Orenburg State University, Orenburg, Russia
3 First Moscow State University named I.M. Sechenov

Prolactin is mainly secreted from the lactotroph cells in the anterior pituitary, whose production is controlled by dopamine. Prolactin can be also produced in extrapituitary tissues, such as the mammary glands, placenta, uterus, prostate, brain where it may act as an autocrine or paracrine factor. Prolactin has some isoforms with different molecular weight, locations and biological functions. While is not an obligate lymphopoietic hormone, prolactin can has effects on the immune system. Nevertheless, hematopoietic cells in murine bone marrow and thymus express the prolactin receptors, but the precise frequency is unknown. The prolactin receptors can be also expressed on cells that mediate natural immunity, including NK cells and macrophages. In conditions in which glucocorticoid levels are elevated, prolactin may reduce the immunosuppressive effects of glucocorticoids, thus providing a mechanism that leads to a homeostatic
normalization of cellular functions.