Stress & Adaptation

Question 1

Homeostasis

Answer 1

-State of constancy
-Requires feedback control systems
-Integrates a variety of body systems
Cannon’s 4 features:
-Mechanisms to maintain constancy
-Change from “steady-state” causes a response
-Response is multifactorial & cooperative
-Simultaneous or successive
“Organized self-government”

Question 2

Eustress

Answer 2

Controllable (mild/brief) periods of stress contributing to emotional and intellectual growth

Question 3

Allostasis

Answer 3

Interactive physiologic changes in neuroendocrine, autonomic, and immune systems in response to real or perceived challenges/threats to homeostasis

It increases chance of survival!

Question 4

Stress Definition

Answer 4

“A state manifested by a specific syndrome of the body developed in response to any stimuli that made an intense systemic demand on it”

Question 5

Endogneous & Exogenous Stress

Answer 5

Stressor

1. Endogenous (within the body)
2. Exogenous (outside the body)

Response to stress dependent upon:

• Properties of stressor
• Condition of person being stressed

Factors affecting condition are:

• Internal (genetic, age, gender)
• External (environmental exposure, life experiences, dietary, social support)

Question 6

General Adaptation Syndrome Stages

Answer 6

1. Alarm Stage
   - SNS & HPA axis stimulation
   - Release of catecholamines & cortisol
2. Resistance Stage
   - Body responds and adapts
   - Cortisol levels drop
3. Exhaustion Stage
   - Resources are depleted
   - Damage to systems if prolonged

Question 7

Neuroendocrine System Response

Answer 7

• Release of neurohormones result in
• Energy
• Sharpened focus & awareness
• Increased cerebral blood flow and glucose utilization
• Enhanced CV & respiratory function
• Shunting of blood to brain/muscles
• Modulation of immune response
• Inhibition of reproductive function
• Decreased appetite

Question 8

Neurohormones involved in stress

Answer 8

Catecholamines
Cortisol:
- Potentiates epinephrine and glucacon
Decreases non-essential energy-using activities (metabolic rate, reproductive, osteoblasts, rbc/wbc production, immune system)

Angiotensin II
Aldosterone
ADH

Question 9

Sympathetic System—“Fight-or-Flight”Response

Answer 9

• Rapid response to trauma and emergency
• Epinephrine & norepinephrine both released
• Both attach to adrenergic receptors on cells
• Blood pressure restored
• Blood flow to skin, guts, and kidneys reduced
• Skin becomes pale
• Urine production decreases
• GI activity decreases

look at slides 12 & 13

Question 10

Cortisol—The “Stress Hormone”

Answer 10

• Helps regulate the stress response
• Diverts metabolism from building to supplying energy for dealing with the stress
• Causes signs and symptoms of chronic stress
• Alters glucose, fat, and protein metabolism
• Suppresses inflammatory and immune response

Question 11

Effect of Stress on Immune System

Answer 11

• Decreased immune cell production
• Decreased thymus activity (eventual atrophy)
• Fewer t-lymphocytes
• Monocytes/lymphocytes release inflammatory mediators and cytokines which interfere with brain activities
• Exact mechanisms unclear
• Variable from person-to-person

Question 12

Adaptation

Answer 12

-The ability to adapt is influenced by coping mechanisms /strategies, both emotional & behavior , attempting to maintain physiologic and psychosocial homeostasis

Question 13

Factors affecting ability to adapt

Answer 13

• Time available to adapt
• Genetic endowment/acquisition
• Age
• Gender
• Health status
• Nutrition
• Sleep-wake cycles
• Hardiness (ability to conceptualize stressors as a challenge rather than a threat)
• Psychosocial factors (support/family/friends)

Question 14

What Can The Acute Stress Response be Caused by?

Answer 14

1. Threat to physiologic environment
   -Moment-to-moment feedback mechanisms specific to threat
   Eg: baroreceptors response to position change
2. Threat to psychosocial environment
   -Response is not specific, and therefore may be inappropriate and sustained
   Eg: death of family/friend/pet

Question 15

Affects of Acute Stress

Answer 15

ANS result in arousal, alertness, vigilance, cognition, focused attention, appropriate aggression
If pre-existing health issue, ANS is already “pushed”

HPA axis response is crucial
Resultant hyperglycemia is not understood well but results in poorer outcomes for serious illness
Low-dose insulin has positive effect

If healthy, redirection of health-promoting activities may (will?) result

Question 16

Chronic Stress Response

Answer 16

Occurs when
Component of system fails
Original stimulus is prolonged/adaptation exhausted
Results in over-reaction or under-reaction

Examples of chronic stress manifestations:
Necrotizing gingivitis
Herpes Simplex Virus (HSV) 1
Rhinovirus infections
Exacerbation of any disease process

Question 17

Posttraumatic Stress Disorder (PTSD)

Answer 17

-Chronic activation of stress response d/t significant traumatic event
-Traumatic event = actual or threatened death/major injury
Combat
Major accident/bombing
Environmental
Rape
Child abuse

Question 18

PTSD patho

Answer 18

• Increased levels of catecholamines & thyroid hormones
• Decreased cortisol levels
• Symptom Triad
• Present together x 1 month /and/
• Clinical symptoms or functional impairments

Question 19

PTSD Symptom Triad

Answer 19

1. Intrusion
   - Flashbacks/nightmares of event
2. Avoidance
   - Emotional numbing
   - Depression
   - Survivor guilt
3. Hyperarousal
   - Irritability/anxiety
   - Exaggerated startle reflex
   - Difficulty concentrating/memory problems
   - Increased concern over one’s safety
   - Sleep disturbances

Question 20

PTSD increases risk for…

Answer 20

Depression
Panic disorder
Generalized anxiety disorder
Substance abuse
Physical illnesses (e.g. HTN, asthma, chronic pain syndrome)

Question 21

Treatment options for PTSD

Answer 21

Main Goals
- Avoid poor coping behaviours
- Provide stress-reducing strategies
Relaxation Techniques
Guided Imagery
Music Therapy
Massage Therapy
Biofeedback

Question 22

Factors affecting the ability to adapt

Answer 22

> Physiologic Reserve
-Ability of the body systems to increase their function 
RBCs, HR, vasodilation/constriction
> Anatomic Reserve
-Paired organs