The peripheral nervous system and autonomic pharmacology

Question 1

What are the actions and characteristics of the sympathetic system

Answer 1

Functions as a complete system and discharges as a whole unit
fight or flight

Question 2

what are the actions and characteristics of the parasympathetic system

Answer 2

not a single entity, never discharges as a whole system
rest and digest

Question 3

What is the process of neural signaling

Answer 3

involves neurotransmission and the synapse.

Question 4

What is the process of synaptic transmission

Answer 4

depolarization of a presynaptic nerve terminal from an action potential leads to the release of neurotransmitters into the extra cellular fluid between the presynaptic and postsynaptic cells.

Question 5

what are the classes of the autonomic drugs and how they achieve their effects

Answer 5

the cholinergic (parasympathomimrtic) drugs act on receptors activated by acetylcholine
The adrenergic (sympathomimetic) drugs act on receptors stimulated by noradrenaline or adrenaline

Question 6

What are the two arms of the nervous system?

Answer 6

Central Nervous System (CNS) & Peripheral Nervous System (PNS)

Question 7

What is an Afferent neuron in PNS

Answer 7

Are the axons of sensory neurons carrying away sensory information for all over the body INTO the spine

Question 8

What is a efferent neuron in PNS

Answer 8

are the axons of spinal cord motor neurons that carry motor-movement signals OUT of the spine into the muscles.

Question 9

What are the two branches of the efferent peripheral nervous system?

Answer 9

somatic nervous system and autonomic nervous system

Question 10

Define ganglia

Answer 10

a structure containing a collection of nerve cell bodies also known as a relay station

Question 11

What is a difference between the Parasynthetic and sympathetic systems?

Answer 11

Parasynthetic - Long preganglionic axons
Sympathetic - Short preganglionic axons

Question 12

What are the divisions of the sympathetic divison

Answer 12

thoracic and lumbar segments

Question 13

What are the divisions of the parasympathetic divison

Answer 13

brain and sacral segments

Question 14

what are the primary neurotransmitters for the sympathetic division?

Answer 14

noradrenaline and adrenaline

Question 15

what are the neurotransmitters for the parasympathetic division?

Answer 15

acetylcholine

Question 16

What is an action potential?

Answer 16

the action potential travels the length of the axon and causes a release of neurotransmitter into the synapse. The action potential and consequent transmitter release allow the neuron to communicate with other neurons.

Question 17

What does an action potential look like?

Answer 17

1, resting potential
2, Depolarisation - voltage-gated NA+ channels
3, Repolarisation Volted-gated K+ Channel
4, Resting Potential Na+/K+ pump

Question 18

What is neurotransmission?

Answer 18

is a process of effective transfer and integration of information in the nervous system

Question 19

what are the neurotransmitters?

Answer 19

Are the molecules used to transmit messages between neurons, or from neurons to effectors (eg muscles).

Question 20

How do ANS drugs produce their primary therapeutic effect?

Answer 20

by mimicking (stimulating) or altering (blocking) the functions of the ANS

Question 21

What are the steps of synaptic transmission

Answer 21

1. transmitter synthesis and storage
2. Release of transmitter
3. Receptor binding
4. Termination of transmission

Question 22

What is the pharmacology of cholinergic drugs?

Answer 22

these drugs are classified are either direct or indirect acting agents. The acting agents act directly on the parasympathetic receptors and the indirect acting drugs work in two different methodss either: cause the relase of the neruotransmitter which then goes to the recepto site or to inhibt the enzyme acetylcholinesterase

Question 23

What are the cholinergic drug action /mechanisms? (Cardiovascular, gastrointestinal, eyes)

Answer 23

Cardiovascular : usually the pt experiences bradycardia and a decrease in blood pressure and cardiac output.
Gastrointestinal: drugs excite the smooth muscle of the GIT and cause increase in activity. motility, and secretion.
Eye: These drugs cause miosis and a decrease in intraocular pressure.

Question 24

What do anticholinergic drugs do?

Answer 24

prevent the action of acetylcholine at postganglionic parasympathetic endings.
Acetylcholine still just released by the receptor site by completely blocked.

Question 25

What are the drug application for anticholinergic drugs?

Answer 25

preoperative medication - inhibit salivary and bronchial secretions
GIT- decreases gastrointestinal motility and can be used to treat ulcers, diarrhea, and hypermotility.

Question 26

What does an adrenergic drug do?

Answer 26

stimulates A and B adrenoreceptors throughout the body, can be classified as having a direct action, indirect action or mixed action.

Question 27

What are the adrenergic agonist effects?

Answer 27

Alpha 1- Vasoconstriction
Beta 1- Cardiac Acceleration
Beta 2- Bronchodilation

Question 28

What is an antiadrenergic drug?

Answer 28

competitively inhibit a and B receptor sites

Question 29

What are the application of antiadrenergic drugs?

Answer 29

These drugs are used to treat hypertension, arrhythmias, heart failure, symptoms of hyperthyroidism, etc