In vitro effects of noradrenaline and corticosterone on the activity of macrophages and T lymphocytes of SPF chickens

Abstract

The bidirectional interactions between the Central Nervous System (CNS) and the Immune System (IS) are already well established. Stress activates the CNS, inducing modification of the immune system that decrease the resistance to infections. Studies have shown of the relationship between the hypothalamic-pituitary-adrenal axis (HPA) and the sympathetic nervous system, releasing the respective mediators corticosterone (CORT) and noradrenaline (NA), with the modulation of the immune system. Different stressors, as heat stressor, is cause of concern on poultry production, and modify HPA axis activity (increase of CORT) and of SNAS (increase of NA). The NA and the CORT act on the immune cells, causing immunosuppression and, consequently, increase the susceptibility to pathogens. Studies in vivo and in vitro show that the NA and CORT can inhibit or stimulate the immune response of animals, observed by the increase or decrease of T lymphocytes proliferation, macrophage activity and the production of cytokines by these cells. The immune cellular system is essential for controlling viral infections and in the induction of vaccine immunity. Thus, the analysis of T lymphocytes became the focus of interest of studies on immunity in various infectious diseases. Another component of the immune system is the macrophage; the classical component of innate immunity is considered the best example of a neuroendocrine-immune cell, since these cells answer to countless hormonal mediators, neurotransmitters and cytokines. It is known that the lymphocytes T and macrophages present receptors for glucocorticoids and noradrenaline (± and ² adrenergics receptors), being modulated by these two chemical substances. Taking this into consideration, the current work aims to continue the on avian neuroimmunomodulation research line. .Specifically, we are looking for in vitro effects of the two main mediators of stress, the corticosterone and the noradrenaline on the proliferation of T lymphocytes and the activity of macrophages collected of SPF chickens. (AU)