382: Glands, Gooseflesh, and Hormones

1. Autonomic Nervous System (ANS)
1. Has 2 systems that control opposing reactions
1. Sympathetic Nervous System (SNS)
1. SNS kicks into action during perceived emergencies
2. Mediate vigilance, arousal, activation, and mobilization.
3. Mediates the four F's of behavior
1. Flight, fight, fright, ans sex
4. The nerve endings release epinephrine and norepinephrine
1. These are the chemical messengers that get things going
2. Parasympathetic Nervous System (PNS)
1. Mediates calm, and vegetative activities.  Everything but the four F's.
2. Promotes growth, energy storage, and other optimistic processes.
3. Many safety systems exist so both systems cannot be simultaneously turned on
2. Your Brain: The Real Master Gland
1. Neurotransmitter
1. A hormone that travels from one neuron to another causing the second neuron to do something different (epinephrine)
2. Hormone
1. If a neuron (or any cell) secretes a messenger that instead of just affecting a single neuron it affects a broad amount of things.
3. The Brains Role
1. Roger Guillemin and Andrew Schally
1. Found that the brain was secreting hormones that controlled what glands should do
2. The brain is the master gland
3. Hormones of the Stress Response
1. Glucocorticoids
1. Steroid hormone
2. Secreted by the adrenal gland, they often act in ways similar to epinephrine.  Epinephrine acts within seconds; glucocorticoids back this activity up over the course of minutes or hours
3. Glucocorticoids along with epinephrine and norepinephrine are the workhouses of the stress response
2. When something stressful happens...
1. Hypothalamus secretes releasing hormones into the hypothalamic-pituitary circulatory system to get things rolling.  
1. The principle releaser is CRH (corticotropin releasing hormone)
2. CRH triggers the pituitary to release ACTH (aka corticotropin)
3. ACTH enters the blood stream, gets to the adrenal gland and triggers the release of glucocorticoids
3. Glucagon
1. Hormone released by the pancreas
4. These three hormones (glucocorticoids, glucagon, and SNS) are essential for mobilizing energy during stress
4. Complications
1. Shelley Taylor
1. "Tend and Befriend" vs "Fight or Flight"
1. Taylor believes the "tend and befriend" is the female version of "fight or flight" that is underemphasized because of male scientists focusing on male participants
2. There is opposition to her female vs male ideas but what has been accepted widely is that at time stress is "fight or flight" and at other times it can be "tend or befriend" in both men and women