L22 Pharmacology

Question 1

what type of communication occurs between nerves and target cells?

Answer 1

chemical (neurotransmitters)

Question 2

what type of communciation occurs between nerve cells?

Answer 2

electrical (action potential) and chemical (neurotransmission)

Question 3

how are neurotransmitters released from pre-synaptic terminal across synaptic cleft?

Answer 3

excotyosis

Question 4

how do they enter neighbouring neuron?

Answer 4

they don’t. they bind to receptors in post-synaptic cleft to cause a stimulated response in the neuron (action potential)

Question 5

do action potential amplitudes differ?

Answer 5

no they all have the same amplitude no matter the stimulus

Question 6

do action potentials have different frequencies?

Answer 6

yes

Question 7

what does an increas of action potential frequency mean?

Answer 7

more neurotransmitters are being released - more of an effect on target cell

Question 8

what is the common pathway by which CNS controls skeletal activity?

Answer 8

Efferent nervous system -> motor nervous system

Question 9

what neurotransmitter is present at a neuro-muscular junction?

Answer 9

acetylcholine, ACh

Question 10

what type of receptor does ACh bind to on muscle cells? what does this mean?

Answer 10

nicotinic, they also bind nicotine neurotransmitters

Question 11

what happens when ACh binds to nicotinic receptors?

Answer 11

it triggers a response - influx of Ca2+ ions which allow muscle depolarisation and contraction

Question 12

what causes the muscle to contract?

Answer 12

end plate potential from

Question 13

how does the signal stop/ muscle contraction stop?

Answer 13

acetylcholinesterase enzyme inactivates acetylcholine, end plate potential stops - contraction stops

Question 14

what substance can cause excessive muscle contraction?

Answer 14

venom from black widow spider - causes explosive release of acetylcholine and organophosphates like sarin gas

Question 15

what effect does high concentration of acetylcholine have on muscle cells?

Answer 15

pro-longed depolarisation can lead to fatigued muscle and respiratory failure

Question 16

what substance can cause lack of acetylcholine?

Answer 16

botulinum blocks release of acetylcholine and curare blocks binding of ACh with nicotinic receptors

Question 17

what effect does low concentrations of acetylcholine have?

Answer 17

inactivated muscles, can cause paralysis

Question 18

what medical purpose does botulinum have?

Answer 18

botox and prevents rigid contraction in skeletal muscle after strokes

Question 19

what is the autonomic nervous system composed of?

Answer 19

parasympathetic and sympathetic systems

Question 20

what knowledge allows development of target drugs?

Answer 20

types of neurotransmitters and receptors involved and pattern of receptor dispersion

Question 21

what system is the adrenal medulla part of?

Answer 21

endocrine and sympathetic nervous system

Question 22

what are adrenal glands?

Answer 22

modified ganglia

Question 23

how do parasympathetic and sympathetic systems work opposingly in relation to the eye?

Answer 23

P - contricts pupil/ S - dilates pupil

Question 24

how do parasympathetic and sympathetic systems work opposingly in relation to the salivary gland?

Answer 24

P - stimulates secretion/ S - Inhibits secretion

Question 25

how do parasympathetic and sympathetic systems work opposingly in relation to the lungs?

Answer 25

P- constricts bronchi/ S- relaxes bronchi

Question 26

how do parasympathetic and sympathetic systems work opposingly in relation to the heart?

Answer 26

P- slows heart/ S- accelerates heart

Question 27

How are adrenal glands stimulated to produce hormones/ neurotransmitters?

Answer 27

sympathetic nerves stimulate pre-ganglionic fibres of adrenal gland and cause secretion

Question 28

what hormones does adrenal gland release?

Answer 28

80% adrenalin, 20% noradrenalin

Question 29

how does the autonomic system regulate physiology of the body?

Answer 29

via parasympathetic system and sympathetic system working opposingly AND acetylcholine and noradrenaline

Question 30

what nerves emerge from CNS always?

Answer 30

pre-ganglionic nerves

Question 31

pre-ganglionic nerves (efferent) always emerge from CNS, what neurotransmitter do they ALWAYS release?

Answer 31

acetylcholine

Question 32

what is the sympathetic pathway beginning from CNS?

Answer 32

1) ACh is secreted from pre-ganglionic neuron 2) Noradrenalin is secreted from post-ganglionic neuron OR 2) Epinephrine/ Adrenalin is released from adrenal gland

Question 33

what is the parasympathetic system beginning from CNS?

Answer 33

ACh is released from pre-ganglionic neuron and post-ganglionic neuron

Question 34

what does noradrenalin/ adrenalin from sympathetic pathway bind with?

Answer 34

effector cells with adrenergic receptors

Question 35

what does ACh from parasympathetic pathway bind with?

Answer 35

effector cells with muscarinic/ nicotinic cholinergic receptors

Question 36

what neurotransmitters do pre-ganglionic nerves always secrete?

Answer 36

ACh

Question 37

what neurotransmitters do post-ganglionic nerves secrete?

Answer 37

in sympathetic pathway: noradrenalin | in parasympathetic pathway: ACh

Question 38

what ACh and NA/Ad receptors do tissues have that are innervated by autonomic nervous system?

Answer 38

nicotinic cholingeric receptors and muscarinic cholinergic receptors (ACh) alpha and beta adrenergic receptors (NA/Ad)

Question 39

what do receptor agonists do?

Answer 39

bind to same receptor as neurotransmitter and cause an effect similar to neurotransmitter

Question 40

what do receptor antagonists do?

Answer 40

bind to receptor and block neurotransmitter response

Question 41

what is salbutamol?

Answer 41

a pharmalogical angonist that mimics effect of NA and Ad

Question 42

what causes widening/dialtion of bronchioles?

Answer 42

pre-ganglionic sympathetic nerves in lungs secrete adrenalin and bind to Beta adrenergic receptors on bronchioles causing dialtion (agonist - salbutamol)

Question 43

sympathetic nervous system accelerates heart rate and force of contraction, how do you stop this pharmalogically?

Answer 43

beta blockers lower heart rate and blood pressure

Question 44

what is the blood-brain barrier?

Answer 44

arrangement of blood vessels and glial cells along with neurons

Question 45

what does prozac do?

Answer 45

blocks serotonin uptake

Question 46

what is L-dopa?

Answer 46

a precursor of dopamine, can get passed blood brain barrier and allieviate symptoms of Parkinson's

Question 47

Common Neurotransmitters

Answer 47

acetylcholine, dopamine, noradrenaline, serotonin, histamine, glycine, glutamate, aspartate, GABA