Approach, 11th Edition by Linda E. McCuistion Chapter 1-58 |
9780323793155 | All Chapters with Answers and Rationals
Adrenergic agonists - ANSWER: drugs that stimulate and mimic the actions of the sympathetic
nervous system
adrenergic agonists act on one or more adrenergic receptor sites located in the effector cells of
muscles, such as: - ANSWER:
- heart
- bronchiole walls
- GI tract
- urinary bladder
- ciliary muscle of the eye
Four main receptors - ANSWER: alpha1, alpha2, beta1, beta2
ALPHA-adrenergic receptors - ANSWER: blood vessels, eyes, bladder, prostate
What happens when alpha1 receptors in vascular tissue of muscles are stimulated? - ANSWER: blood
vessels constrict, increasing peripheral resistance and blood return to heart
What happens when alpha2 receptors are stimulated? - ANSWER: inhibit the release of
norepinephrine, leading to a decrease in vasoconstriction
Where are alpha 1 receptors located? - ANSWER: vascular smooth muscle
Where are alpha 2 receptors located? - ANSWER: postganglionic sympathetic nerve endings
Where are beta 1 receptors located? - ANSWER: Heart and kidney
Stimulation of beta 1 receptors causes: - ANSWER: increase in myocardial contractility and heart rate
Where are beta 2 receptors found? - ANSWER: smooth muscle of lung & GI tract, liver, uterine muscle
Stimulation of beta 2 receptors causes: - ANSWER: relaxation of smooth muscle in lungs, decrease in
GI tone and motility, glycogenolysis, relaxation of uterine muscle
Dopaminergic receptors are located in the: - ANSWER: renal, mesenteric, coronary, and cerebral
arteries
When dopamine stimulates dopaminergic receptors: - ANSWER: vessels dilate and blood flow
increases
How are transmitters inactivated? - ANSWER: (1) reuptake of the transmitter back into the neuron (2)
enzymatic transformation or degradation (3) diffusion away from the receptor
After the neurotransmitter has performed it's function, the action must be stopped to: - ANSWER:
prevent prolonging the effect
Two enzymes that inactivate norepinephrine: - ANSWER: monoamine oxidase (MAO) - inside the
neuron
catechol-O-methyltransferase (COMT) - outside the neuron