Workshop The Physiologic Response to Stress - PPT PDF

 Session aims Explain the “systemic” physiological response to stress driven by increased activation of the autonomic nervous system and endocrine system. Explore the physiological response to stress in terms of a broad protective and/or preparatory response.  L...

 Session aims Explain the “systemic” physiological response to stress driven by increased activation of the autonomic nervous system and endocrine system. Explore the physiological response to stress in terms of a broad protective and/or preparatory response.  LEARNING OBJECTIVES 1. Review the key structures and functions of the autonomic nervous system. 2. Explain the role of the endocrine and nervous system in the regulation and coordination of organ system function. 3. Explain the role of the hypothalamus in the coordination of output from the nervous system and the pituitary glands. 4. Explain the general neuroendocrine response to stressors. 5. Describe the role of the adrenal gland in response to stress.  STRESSORS Both physical and/or psychological factors can cause or be perceived as stressors. Stressors can have an internal or external origin. Frequently the way in which the individual perceives and processes the stressor(s) has a significant impact on the response (outcome).  Homeostasis, Allostasis and Allostatic load The stress response is designed to rapidly bring the body back to a stable state, in order to increase the probability of survival. The term allostasis describes the physiologic changes in neuroendocrine, autonomic and immune systems that occur in response to challenges to homeostasis (real or perceived). Accumulation of these allostatic changes has been called the allostatic load. This concept has been used to measure the cumulative effects of stress on humans.  Physiologic response Allostasis Short-term adaptative “homeostatic” state: adapted to stressors Environmental stressors, major life events, trauma, abuse Adaptation  Stressor Higher brain centre Hypothalamus Autonomic Endocrine nervous system system Coordinated response to stress  ROLE OF THE HYPOTHALAMUS Cerebral cortex Limbic system Thalamus RAS Spinal cord Hypothalamus Locus ceruleus Anterior pituitary Autonomic nervous system Adrenal gland Adrenal medulla Cortisol The physiological response to stress can involve both a rapid (acute) response and a slower (chronic) response Autonomic Endocrine system nervous system = (anterior and rapid, acute posterior pituitary)= response slower, chronic response  The diverse physiological responses to stress - a broad protective response Adapted from McCance et al 2010, Pathophysiology, the biologic basis for disease in adults and children, Mosby Inc Additional resources Guyton & Hall. Medical Physiology. Chapters 61 and 78 (Review the autonomic nervous system and adrenocortical hormones). McCance et al., 2010. Pathophysiology. The Biologic Basis for Disease in Adults and Children. Chapter 10: Stress and Disease Videos: https://www.youtube.com/watch?v=T5ScIqPnqf8&t=1468s