NEUROENDOCRINE FACTORS IN SUSCEPTIBILITY TO INFLAMMATORY DISEASE - FOCUS ON THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS

Communication between the central components of the stress response an d the immune system plays an important role in susceptibility to infla mmatory disease. This communication occurs through hormonal and neuron al mechanisms. Hormonal mechanisms involve activation of the hypothala mic-pituitary-adrenal (HPA) axis by immune system products, e.g. cytok ines. The stimulated HPA axis regulates immune responses through the i mmunosuppressive effects of glucocorticoids. Neuronal mechanisms inclu de direct innervation of immune organs. Cytokine activation of the HPA axis and the resultant glucocorticoid-induced suppression of immune a nd inflammatory responses represent an important mechanism whereby the central stress response modulates peripheral inflammation. Interrupti on of this communication is associated with exacerbation of inflammato ry disease. Conversely, intracerebroventricular transplantation of hyp othalamic tissue from inflammatory resistant rats into susceptible rat s reduces peripheral inflammation by more than 85%.