Psychosomatic medicine

A psychosomatic framework.

• A psychosomatic framework.
• Two major facets of stress response.
• “Fight or Flight” response is mediated by hypothalamus, the sympathetic nervous system, and the adrenal medulla.
• If chronic, this response can have serious health consequences.
• The hypothalamus, pituitary gland, the adrenal cortex mediate the second facet.

Stressors activate noradrenergic systems in the brain and cause release of catecholamines from the autonomic nervous system.

• Stressors activate noradrenergic systems in the brain and cause release of catecholamines from the autonomic nervous system.
• Stressors also activate serotonergic systems in the brain, as evidenced by increased serotonin turnover.
• Stress also increases dopaminergic neurotransmission in mesoprefrontal pathways.

CRF is secreted from the hypothalamus.

• CRF is secreted from the hypothalamus.
• CRF acts at the anterior pituitary to trigger release of ACTH.
• ACTH acts at the adrenal cortex to stimulate the synthesis and release of glucocorticoids.
• Promote energy use, increase cardiovascular activity, and inhibit functions such as growth, reproduction, and immunity.

• Inhibition of immune functioning by glucocorticoids.
• Stress can also cause immune activation through a variety of pathways including the release of humoral immune factors (cytokines) such as interleukin-1 (IL-1) and IL-6.
• These cytokines can themselves cause further release of CRF, which in theory serves to increase glucocorticoid effects and thereby self-limit the immune activation.

• High level of Cortisol results in suppression of immunity which can cause susceptibility to infections and possibly also in many types of cancer.
• Changes in the immune system in response to stress are now very well established.

• Immune suppression in response to stress occurs even after removal of the adrenal gland !!.
• There appears to be an alternative path, other than through the adrenals, for the brain to influence the immune response.
• Psychoneuroimmunology