The first line of defense is local barriers such as the skin, peritoneum, etc, and inflammation due to immunoglobulins, or antibodies. If those fail to block or destroy the antigens, the cell-mediated immune response and the humoral immune response kick in. Studies by Manuck, et al in 1991 showed that psychological stressors induced cell division among CD8 cells, thereby increasing the number of CD8 cells and suppressing immune function. However, this response was only seen in those subjects who also showed high heart rate change and catecholamine change during the stressors. High reactors are significantly affected by stress, as shown by a significant increase in heart rate, blood pressure, catecholamines, and CD8 cells.
Catecholamines are chemicals produced by the body that work in nerve transmission.
The three main catecholamines include dopamine, epinephrine, and norepinephrine. Epinephrine and norepinephrine are the catecholamines most commonly measured in stress experiments, and both increase under stress. In asthma, a disease which involves both external and internal factors, it is the internal factor that is most affected by acute effects of psychological stressors. Studies have shown that children with chronic asthma inprove considerably when away from their parents. The changes may have resulted from removal of an interaction that produced frequent stressful situations.