Interrelation of Body systems

Interrelation of Body systems

  • Neurochemical links among the nervous, endocrine, and immune systems. The communication among these 3 systems is bidirectional travels back and forth through neuropeptides, cytokines, and endocrine hormones respectively
    • Central nervous system
      • The hypothalamus has many functions that assist in adaptation to stress by secreting neuropeptides that communicate with immune systems and endocrine systems
      • The cerebral cortex evaluates the stressor in light of past experiences and future consequences
      • The limbic system is an important mediator of emotions and behavior. When the limbic system is stimulated, emotions, feelings, and behaviors can occur that ensure survival and self-preservation.
      • The reticular formation contains reticular activating system (RAS), which sends impulses contributing to alertness to the limbic system and cerebral cortex. When the RAS is stimulated, it increases its output of impulses, leading to wakefulness. Stress usually increases the degree of wakefulness and can lead to sleep disturbances.
    • Immune system
      • Cytokines are released that communicate with the central nervous systems and endocrine system
      • Stress affects immune function by¬†
        • Decreasing the number and function of natural killer cells
        • Decreasing lymphocyte proliferation
        • Altering production of cytokines (soluble factors secreted by white blood cells and other cells, e.g., interferon, interleukins)
        • Decreasing phagocytosis
    • Endocrine system
      • The SNS stimulates the adrenal medulla to release epinephrine and norepinephrine
      • The stress response involves increases in cardiac output (resulting from the increased heart rate and increased stroke volume), blood glucose levels, oxygen consumption, and metabolic rate