Pathophysiology Chaptert 9 Stress & Adaptation

Front 1

Define Homeostasis.

Back 1

The concept of a stable internal environment, achieved through a system of carfull coordinated physiological processes that oppose change.

Front 2

Describe negative feed-back.

Back 2

When a function or value decreases below the set point of the system, the feed-back mechanism to increase; and whent it increases above the set point it causes it to decrease.

Front 3

Describe an example of negative feed-back.

Back 3

increases in blood glucose stimulate the release of insulin that lowers blood sugar, low blood sugar causes inhibits insulin release and stimulates glucose release.

Front 4

Describe positive feed-back.

Back 4

this mechanism interjects instibility; The initiating stimulus produces more of the same stimulus.

Front 5

Give an example of positive feed-back.

Back 5

The hormone oxytosin stimulates uterine contractions, which stmulates more contractions: the cycle continues until the baby is born and the cycle is broken.

Front 6

Define Stress.

Back 6

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

Front 7

explain the general adaptation syndrome.

Back 7

The role of the hypothalamic-pituitary-adrenal axis in the stress response.

Front 8

explain the GAS theory.

Back 8

general-the effect is a general systemic reaction. adaptive-because the resonse was in reaction to a stressor. syndrone-the physical manistations were coordinated and dependent on each other.

Front 9

what are the stages of GAS

Back 9

alarm stage
resistance stage
exhaustion stage

Front 10

define alarm stage.

Back 10

a generalized activation of the HPA axis, resulting in the release of catecholamines and cortisol.

Front 11

define resistance stage

Back 11

the body selects the most effective and economical channels of defense. The cortisol levels drop because they are no longer needed.

Front 12

define exhaustion stage

Back 12

if the stressor is prolonged or overwhelms the bodies defenses, resoorces are depleted.

Front 13

list the hormones associated with the stress response.

Back 13

catecholamine (NE & Epi), CRF, ACTH, Glucocortico hormones(cortisol), Mineralocorticoid hormones (aldosterone), ADH.

Front 14

List the source of these hormones and describe their physiologic effects.
(NE, EPI)

Back 14

(NE, EPI)- Locus ceruleus, adrenal medulla.
< insulin, > glucagon resulting in
>glycogenolysis,
gluconeogenisis,lipolysis, proteolysis. > HR, cardiac contractility & bronchiodilation.

Front 15

Corticotropin releasing factor (CRF)

Back 15

Hypothalamus.
stimulates ACTH release from anterior pituitary and > activity in neurons in locus ceruleus.

Front 16

Adrenocorticotropic hormone (ACTH)

Back 16

Anterior pituitary.
stimulates the synthesis and release of cortisol.

Front 17

Glucocorticoid hormones.
(cortisol)

Back 17

adrenal cortex.
potentiates the action of epi and glucagon. inhibits the release and/or actions of reproductive hormones & TSH, & produces a < in immune cells and inflammatory mrdiators.

Front 18

Mineralcorticod hormones (aldosterone)

Back 18

adrenal cortex.
> sodium absorption by the kidneys.

Front 19

Antidiuretis hormone (ADH)

Back 19

Hypothalamus, posterior pituitary.
> water absorption by the kidneys; produces vasoconstriction of blood vessels: and stimulates the release of ACTH.

Front 20

discuss neuroendocrine responses.

Back 20

It relies on communication along neuronal pathways of the cerebral cortex,limbic system, thalamus, hypothalamus,pituitary gland, and the reticular activating system.

Front 21

cerebral cortex

Back 21

involved with vigilance, cognition, and focused attention.

Front 22

limbic system

Back 22

emotional components ( fear, excitement, rage, anger) of the stress response.

Front 23

thalamus

Back 23

functions as the relay center and is important in recieving, sortingout and distributing sensory input.

Front 24

hypothalamus

Back 24

coordinates the response of the autonomic nervous system.

Front 25

reticular activating system

Back 25

modulates mental alertness, ANS activity, and skeletal muscle tone, using input from other neural structures.

Front 26

what is the locus ceruleus

Back 26

is densly populated with neurons that produce NE and is thought to br the central intergrating site for the ANS response to stress.

Front 27

What is corticotropin - releasing factor

Back 27

a small peptide hormone that has both an important role as a endrocrine regulator of pituitary and adrenal activity, and a neurotransmitter involved in ANS activity, metabolism and behavior

Front 28

how does CRF effect the stress response

Back 28

CRF from the hypothalumus induces ACTH from the anterior pituitary gland. ACTH in turn stimulates the adrenal gland to synthesize and secrete cortisol.

Front 29

what effects do glucocorticoid hormones have

Back 29

they have both direct and indirect effects that mediate the stress response. enhance the actions of other hormones, or suppress other components of the stress system.

Front 30

What are some of the effects of cortisol

Back 30

maintains blood glucose levels by antagonizind the effects of insulin and enhances the effect of catecholamines on the cardiovascular system.

Front 31

Other cortisol functions include

Back 31

supress osteoblast activity, hematopoiesis protein and collegen synthesis, and immune responses.

Front 32

how can cortisol effect thyroid funtion

Back 32

stress induced cortisol also is associated with decreased levels of thyroid hormone and inhibition of conversion of (t4 to the more biologicially active t3)a means to conserve energy.

Front 33

What is the role of ADH in the stress response

Back 33

ADH is involved in the stress response, particularly in hypotensive stress or stress do to fluid volume loss.

Front 34

what role does immune cells play in the stress response.

Back 34

monocytes and lymphocytes can penetrate the blood-brain-barrier where the secrete cytokines and other inflammatory mediators that influence the stress response.

Front 35

What is the most fully evolved mechanism for copind and adaptation to stress.

Back 35

the social responses through which individuals or groups modify their environments, their habits, or both.

Front 36

list some factors that affect the ability to adapt.

Back 36

physiologic and anatomic reserve, time, genetics, age, health status, nutrition, sleep-wake cycles, hardiness, psychosocial factors.

Front 37

define post traumatic stress disorder.

Back 37

chronic activation of the stress response as a result of experiencing a potentially life threatening event.

Front 38

how is PTSD characterized

Back 38

a constellation of symptoms that are experienced as states of intrusion, avoidance, and hyperarousal.

Front 39

define Intrusion

Back 39

the occurrence of flash backs during waking hours or nightmares in which the event is relived.

Front 40

define avoidance.

Back 40

the emotional numbing that occompanies this disorder disrupts important personal relationships. (survivor guilt)

Front 41

define hyperarousal

Back 41

the presence of increased irritability, difficulty in concentration, an exaggerated startle reflex, and concerns over safety.