Exam2Lec1ANSPharmacology Flashcards
what are the 3 Natural catecholamines?
- Dopamine
- Epinephrine
- Norepi
Describe the general mechanism of action for natural catecholamines
They directly stimulate the adrenergic receptors
What are 2 indirect-acting sympathimimetics drugs?
Cocaine and Amphetamine
Describe the general mechanism of action for indirect-acting symphathomimetics
They DO NOT directly stimulate the adrenergic receptors
They elevate the levels of natural catecholamines
What are the 2 mixed-action sympathomimetics drugs?
- ephedrine
- Pseudoephedrine
Describe the general mechanism of action for mixed-action sympathomimetics
Have some effects like natural catecholamines and some effects like indirect-acting symphathomimetics (mainly amphetamine effects)
Autonomic Nervous system
target tissue?
distal synapse lxn?
Post synaptic nerves?
Networks?
Results of denervation?
- Target tissue: visceral organs, glands, smooth muscle
- distal synapse lxn: peripheral ganglia
- Post synaptic nerves: non-myelinated
- Networks: forms networks
- Results of denervation: spontaneous activity
Somatic Nervous system
target tissue?
distal synapse lxn?
Post synaptic nerves?
Networks?
Results of denervation?
- target tissue: skeletal muscle
- distal synapse lxn: cerebrospinal axis
- Post synaptic nerves: myelinated
- Networks: does not form networks
- Results of denervation: paralysis, atrophy
What are the preganglionic and postganglionic neurons for the SNS?
SHORT ACH/Cholinergic preganglionic neurons
LONG Norepi/Adrenergic postganglionic neurons
remeber there are exceptions
What are the preganglionic and postganglionic neurons for the PNS
LONG ACH/Cholinergic preganglionic neurons
SHORT ACH/Cholinergic postganglionic neurons
Does SNS or PNS mainly do broad regulation of the body?
SNS
can also do some orgna specific regulation such as regulating HR.
PNS does organ specific regulation
Neurons in the PNS are found in what region of the spinal cord?
a. cervical
b. thoracic
c. lumbar
d. sacral
cervical
If you are running from a bear, and your SNS is now stimulated, list what sympathetic action occurs to each tissue listed below.
SA node/contractility
Blood vessles in skeletal muscle and coronary
Bronchial smooth muscle
Uterus, bladder, GI tract
Sweat glands
Liver
PNS nerve endings
- SA node/contractility: HR and blood flow to muscle incr
- Blood vessles in skeletal muscle and coronary: dilates/relaxes
- Bronchial smooth muscle: dilates/relaxes to breathe
- Uterus, bladder, GI tract: relaxes (sphinter contracts)
- Sweat glands: you sweat
- Liver: incr gluconeogenesis to breakdown energy
- PNS nerve endings: decr ACh release
opposite for pns
During a symp response, do you want to incr or decr insulin secretion?
Incr insulin secretion lvls to get gluc into cells but not too much where lots of gluc gets stored
During sympathetic response, is the eye dilated or constricted and what muscle is involved?
Eyes are dilated by radial muscle to see better (mydriasis)
adregernic receptor
During parasympathetic response, is the eye dilated or constricted, what muscle(s) are involved?
Constricted by circular muscle and ciliary muscle and aq humor is released so it can repair the eye
Cillary muscle interacts with the trabecular network to relase aqueous humor that repairs the eye
How is homeostasis maintained in the ANS?
Combinations of neurons that send out a signal (efferent) and neurons that are sensing a variety of things from distension to chemicals (afferent)
What are afferent and efferent neurons?
Afferent: Signal going TO CNS
Efferent: Signal going AWAY from CNS
What does NOT have parasymp innervation?
BV, sweat glands, hair follicles, and adrenal medulla
What is the response that helps maintain homestasis in the cardiovascular system? Where can they be found and what triggers a response?
- Baroreceptors (chemo-and mechanoreceptor)
- Carotid sinus and body & Arch of aorta
- Respond to change in blood pressure
What is a common feedback loop in the ANS?
The Baroreceptor Reflex
If there is an incr in MAP, explain how the baroreceptor reflex regulates it
- Incr in BP
- BR senses that and stretches
- Incr firing to vasomotor center
- Parasymp activated
- Decr HR (a little contractile force) to decr CO to then decr BP
REMEBER PNS doesnt inn ventricles so it has no effect on peripheral resistance or venous tone
PNS can only do HR AND LITTLE contrictility
If there is a decr in MAP, explain how the baroreceptor reflex regulates it
- Decr in BP
- BR senses that and decr signal firing to vasomotor center
- Sympathetic is activated
- This incr: HR, Peripheral vascular resistance (constriction), Contractile force, and venous tone
- BP now incr
What parts of the heart are not affected by the parasympethetic output of the baroreceptors?
NO effect on peripheral resistance and venous tone
What is the sympathetic output of the baroreceptor reflex involved in?
- Normal physiological responses
- Pathophysiological (disease or injury) responses (e.g Cardiac Heart Failure)
- Unwanted side effects (E.g vasodilator)
What does inhibition of the sympathetic output of the baroreceptor reflex cause? And explain
Orthostatic hypotension
BP drops when standing up b/c bv too constricted. Can cause appearance of floaties. Older pts tend to fall and substain hip damages
What does both parasympathetic and sympathetic GANGLIA have?
Both have Presynpatic Cholinergic Neurons
What are the synapses for all parasympathetic target organs?
Cholingeric synapses
A few Symphathetic target organs have choligernic synapses. What are they?
- Sweat Glands
- Vascular system (blood vessels)
Acetylcholine is the primary neurotransmitters in which organs/systems?
Adrenal gland (secrete systemically)
Skeletal muscle
All ganglia
What is the primary neurotransmitter in the somatic nervous system and where is it located?
Acetylcholine
Located in the Neuromusclar Junction