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CV exam 1 wk 1 > ANS > Flashcards

Flashcards in ANS Deck (20):
1

Homeostasis:

Maintaining a stable internal environment within a narrow physiological range amid changing external conditions

2

Inputs to preganglionic neurons:

1. Nucleus of the solitary tract (in medulla): conveys visceral sensory input
2. Other brainstem nuclei: convey environmental stimuli
3. Hypothalamus (in forebrain): conveys internal goals/states

3

The ANS consists of 3 subdivisions

1. sympathetic (flight or fight)
2. parasymp (rest/digest)
3. enteric (semi autonomous control of digestion)

4

Preganglionic: neurotransmitter:

Acetylcholine (ACh)

5

Postganglionic:
Sympathetic: neurotransmitter

Norepinephrine (NE) and epinephrine

6

Postganglionic Parasympathetic: neurotransmitter

ACh

7

Neurotransmitter Receptors:
ACh:

nicotinic vs. muscarinic

8

Neurotransmitter Receptors:
NE:

α- and β-adrenergic

9

Adrenal medulla – functionally, a sympathetic ganglion

1. Innervated by preganglionic sympathetic neurons
2. Releases norepinephrine and epinephrine into bloodstream
3. Widespread sympathomimetic effects (e.g., increased heart rate)

10

Cardiovascular regulation by the nervous system

1. Sympathetic and parasympathetic control of heart rate and force of contraction
2. Baroreceptor reflex
3. Humoral response to low blood pressure

11

ANS regulation of heart rate and force of contraction

1. sympathetic stimulation
2. parasympathetic stimulation

12

ANS sympathetic stim

(via increased NE) –
1. increases blood pressure
2. Increase in heart rate and contractile force
3. Constriction of blood vessels

13

ANS parasympathetic stimulation

(via increased ACh) –
1. decreases blood pressure
2. Decrease in heart rate and
3. decreases contractile force

14

Physiological significance of receptor subtypes

1. Sympathomimetic drugs
2. Parasympathomimetic drugs

15

Sympathomimetic drugs function to

mimic sympathetic activation

16

Sympathomimetic drugs examples

Atropine

17

Atropine is a _____

muscarinic (M2) antagonist in heart

18

atropine does what?

increase HR

19

Parasympathomimetic drugs function to:

mimic parasympathetic activation

20

propranolol results in?

decreases heart rate