Lecture 15- ANS, Endocrine and the Stress Response

Question 1

What links the hypothalamic nuclei. The pituitary gland?

Answer 1

Infundibulum

Question 2

Secreted hormones?

Number and action?

Answer 2

Hypothalamus secretes 9 hormones (inhibitors + releasing)
Hypophyseal portal veins connect to the pituitary gland that secretes 7 hormones that control endocrine organs
These regulate: Growth, Development, metabolism, homeostasis

Question 3

Hypophyseal portal veins

Answer 3

Link capillary beds on the pituitary gland so that the bloo doesn’t have to go back through the heart

Question 4

HPA AXIS?

Answer 4

Hypothalamic- pituitary- adrenal axis

Question 5

Enhancing the alarm response?

Answer 5

Uses the sympathetic nervous system

Question 6

Pathway from cns–actions

Answer 6

1. Sympathetic pre ganglionic neuron stimulated
2. Modified post ganglionic “neurons” act as secretory cells
3. Epinephrine and norepinephrine released into the BLOOD STREAM.

Question 7

difference in response to ANS response?

Answer 7

uses the blood and so is slower acting but is longer lasting in its effects.

Question 8

difference between epinepherin and adrenaline

Answer 8

no difference

Question 9

ANS is immediately backed up by?

Answer 9

stress response of the Adrenal Medulla that is stimulated by ACh from sympathetic pre-ganglionic neurons. Causing NE and E to be released.

Question 10

effects of NE and E from the Adrenal Medulla?

Answer 10

enhanced sympathetic ANS response that floods the system and prolongs effect.

Question 11

stage 1 of the stress response?

Answer 11

fight or flight response

• immediate burst (ANS)
• sympathetic activation
• adrenal medulla involvements
• E and NE release and effects

Question 12

Stage 2 of stress response?

Answer 12

Resistance Reaction
slower, longer lasting
associated with H-P-A cortex
corticosteroid (cortisol) production that dampens inflammation and alters immune response.

Question 13

Stress response as a whole?

Answer 13

• sympathetic autonomic activation
• mobilise resources for immediate physical activity
• glucose and oxygen consumption
• alertness and activity
• ward off danger and flee

Question 14

stage 2 of stress response action?

Answer 14

the Resistance reaction occurs after some time
Corticotropin releasing hormone (CRH) produced by the hypothlamus released into the primary hypophyseal plexus, then portal vein stimulates
Adrenocorticotropin hormone (ACTH) to be produced by the pituitary gland into the blood stream.
Causes Adrenal cortex to Glucocorticoids (eg. Cortisol)
This Cortisol increases the resistance reaction.

Question 15

resistance reaction?

Answer 15

increased glucose, fatty acids, amino acids
sensitized vessels
reduced inflammation
immune suppression

Question 16

second action of Adrenal Cortex?

Answer 16

and increase in K+ and angiotensin II in the blood causes mineral corticoids (eg. aldsosterone) to be relaesed. These incresed blood Na+ and water and decrease blood K+ leading to increase blood volume and pressure.

Question 17

negative feedback effects effects on pituitary gland?

Answer 17

1. high levels of cortisol in blood needs to be removed from blood after the stressor is removed to avoid damage.
2. cortisol inhibits both CRH and ACTH

Question 18

The stress response is a ______ system?

Answer 18

inducable

Question 19

Reasons for effects of stress response?

Answer 19

to meet the immediate danger that is posed to the body. There is no point stopping cancer if you could die from being eaten by a bear.

Question 20

effects of glucocorticoids (eg. Cortisol) ?

Answer 20

1. protein breakdown
2. gluconeogenesis
3. lipolysis
4. vasoconstriction
5. anti-inflammatory
6. immune depression

Question 21

links between the neuroendocrine and immune system?

Answer 21

1. Autonomic nerves go to some lymph tissue
2. hormones (eg. cortisol) influence how some lymph cells act
3. Cytokines- immune hormones have many effects on nervous cells.

Question 22

Short term remedial action?

Answer 22

• change relationship to world
  1. THREAT SYSTEM AROUSAL
  
  • blood (energy), muscle (motor), vigilance (sensory)
    
    2. DAMPEN UNNECESSARY
  • immunity, digestion

Question 23

types of stress?

Answer 23

EUSTRESS
- acute stress that is benficial/helpful in preparing to meet challenges

DISTRESS
- chronic as inducable stress response is turned on too long. associated with undesirable events and potentially harmful.

Question 24

Hostility and the heart?

Answer 24

habitually hostile people have a long term sympathetic activation build up.
the heart must work harder and capillaries constrict.
GREATER RISK OF CARDIAC INFARCT…