figure 11. schematic representation of the interactions between the stress and the immune system. lc/ne: locus ceruleus/norepinephrine-sympathetic system, spgn: sympathetic postgaglionic neurons, crh: corticotropin-releasing hormone, avp: arginine vasopressin, acth: corticotrophin, paf: platelet activating factor, ne/e: norepinephrine/epinephrine,: th1: t-helper lymphocyte 1, th2: t-helper lymphocyte 2. stimulation is represented by solid green lines and inhibition by dashed red lines.