NUR 114 Autonomic Nervous System

ACh

preganglionic neurotransmitter

norepinephrine, epinephrine

SNS postganglionic neurotransmitters

ACh

PNS postganglionic neurotransmitters

monoamine oxidase (MAO), catechol-o-methyl transferase (COMT)

SNS neurotransmitter terminator

acetylcholinesterase

PNS neurotransmitter terminator

dopamine, serotonin, epinephrine, norepinephrine

catecholamines

norephinephrine

made by the nerve cells using tyrosine, becomes dopamine, then ___

depolarizes, sodium, neurotransmitter

action potential ____ axon membrane, ____ travels into the nerve, ____ is released across the synaptic cleft to adrenergic receptor sites

alpha1 receptors

found in blood vessels, the eye, and bladder

alpha1 blood vessels

vasoconstriction, increased blood pressure, increased contractility of the heart

alpha1 eyes

mydriasis

mydriasis

pupil dilation

alpha1 bladder

bladder relaxation

alpha1 prostate

prostate contraction

alpha2 receptor

found in blood vessels and GI smooth muscle

alpha2 blood vessels

decreased blood pressure because of reduced norepinephrine

alpha2 smooth muscle

decreased GI tone and motility

beta1 receptor

found in the heart and kidney

beta1 heart

increased heart contraction, increased heart rate

beta1 kidney

increased renin secretion and angiotensin, increased blood pressure

beta2 receptor

found in GI smooth muscle, lungs, uterus, and liver

beta2 smooth muscle

decreased GI tone and motility

Beta2 lungs

bronchodilation

beta2 uterus

relaxation of uterine smooth muscle

beta2 liver

activation of glycogenolysis, increased blood sugar

CN 3, 7, 9, 10

PNS uses these and sacral neurons for target organs responses

Muscarinic receptors

PNS receptors located in organs such as heart, lungs, GI, bladder, smooth muscle, and sweat glands

Nicotinic receptors

PNS receptors located in the brain, muscle, and adrenal medulla

Direct acting cholinergic agonists

Drugs that work on muscarinic receptors that stimulate the PNS

Indirect acting cholinergic agonist

Stimulates nicotinic receptors by stopping acetylcholinesterase from breaking down acetylcholine

Anticholinergic drugs

Block effects of ACh on cholinergic receptor sites on target organs, blocking PNS