Chapter 4 Autonomous Drugs Flashcards
Vasoconstrictors added to some LA & drugs used to ^ salivary flow are _________
ANS drugs
Some ANS drugs produce oral adverse reactions. Example?
Anticholinergic drugs cause xerostomia
Members of other drug groups have effects similar to those of ANS drugs. Example?
Antidepressants and antipsychotics are drug groups with autonomic side effects, specifically anticholinergic effects
ANS functions in
Regulation of BP, heart rate, GI tract motility, salivary gland secretions, and bronchial smooth muscle.
ANS system relies on
specific neurotransmitters (chemicals released to send messages) and a variety of receptors to initiate functional responses in target tissues
Each division of ANS (PANS and SANS) anatomy
Afferent (sensory) fibers (What’s happening?), central integrating areas (Let’s coordinate all this info! Hey, what did you find out?), efferent (peripheral) motor preg. (This is what’s happening) fibers and postg. fibers (Heart, begin beating!)
The preg. neuron originates in the ________ and passes out to form the _________ at the synapse with the postg. neuron.
CNS, ganglia
Space between preg. and postg. is termed __________
Synapse/synaptic cleft
The postg. neuron originates in the ___________ and innervates ______________________
ganglia, effector organ/tissue
__________ in the CNS give rise to the preg. fibers of the PANS. They originate in _________
Cell bodies; nuclei of III, VII, IX and X cranial nerves and S2-S4 of spinal cord
The preg. fibers of the PANS are relatively ________ and extend near or into _________
long, innervated organ
Distribution of preg. fibers in the III, VII and IX cranial nerves is relatively _______ whereas the X/vagus nerve has a ________ distribution
simple, complex
Postg. fibers of PANS originating in _______, usually ______ and terminate on ________
ganglia, short, innervated tissue
Cell bodies that give origin to the preg. fibers of the SANS span from __________ to the __________. Referred to as “in between” because ________
thoracic (T1), lumbar (L2) portion of the spinal cord. Distribution is between two locations of the innervation of the PANS
Arrangement of SANS produces a ______ diffuse effect than PANS because ____________ then postg. fibers terminate at the ____________
more, a single SANS preg. fiber often synapses with numerous postg. fibers and because adrenal medulla release epi into bloodstream, effector organ or tissues
Adrenal medulla is also innervated by the _________. Functions much as a large _________ with glands in the medulla representing __________
SANS, sympathetic ganglion, postg. component.
When SANS is stimulated, the adrenal medulla releases primarily ________ and a small amount of _________ into systemic circulation
epi, norepinephrine (NE)
PANS is concerned with ________ SANS designed to cope with _________ such as __________.
conservation of body processes (digestion and intestinal tract motility), sudden emergencies such as “fight-or-flight”
SANS stimulates radial smooth muscle producing an _________. PANS stimulates circular smooth muscle producing a __________.
increase in pupil size (mydriasis), decrease in pupil size (miosis)
T/F Sensory fibers in one division can influence motor fibers in another.
True
Neurotransmitter function
carry messages
Communication between nerves or between nerves and effector tissue takes place through __________________
Release of chemical neurotransmitters across the synaptic cleft
Neurotransmitters are released in response to the _____________ to _____________
Nerve action potential, interact with receptor
T/F Receptors are only found on the postsynaptic fiber and effector organ
False; Receptors are usually found on the postsynaptic fiber and effector organ but may be located on the presynaptic membrane
Disposition of the neurotransmitter occurs most often by either its ___________________ or _______________
reuptake into the presynaptic nerve terminal, enzymatic breakdown
Nerves in ANS contain necessary enzyme systems and other metabolic processes to _____________________
synthesize, store and release neurotransmitters
Drugs can modify ANS activity by altering any of what events associated with the neurotransmitters?
synthesis, storage, release, receptor interaction and disposition
Between preg. and postg. neurons
Acetylcholine (ACh) is the neurotransmitter in the synapse (ganglion) formed in this area. Nerves that release ACh are termed cholinergic, also stimulated by nicotine so termed nicotinic as well.
Between postg. and effector tissues
PANS: Neurotransmitter released from postg. nerves is ACh, cholinergic. Because postsynaptic tissue responds to muscarine, termed muscarinic.
SANS: NE is the transmitter released by postg. nerves; designated as adrenergic
Neuromuscular junction
Although not within ANS, neuromuscular junction of skeletal muscle releases ACh, cholinergic
If the postsynaptic tissue is a postg. nerve _______________
Depolarization with generation of an action potential occurs in that neuron
The action of released ACh is terminated by ___________
hydrolysis by acetylcholinesterase to yield the inactive metabolites choline and acetic acid (acetate)
3 ACh receptor sites
PANS, ganglions, neuromuscular junction
Once ACh is released from the presynaptic neuron into the synaptic cleft, it can bind to either ______ or _____________
muscarinic or nicotinic receptor sites
Small doses of ACh bind to ________. Large doses bind to __________
muscarinic, nicotinic receptors
Nicotinic receptors are found in the _______________
neuromuscular junction, PANS, SANS, adrenal medulla, and CNS