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Key Terms

acetylcholine (ACh)
major neurotransmitter of the cholinergic system
adrenergic receptors
mediate responses to epinephrine and norepinephrine; include alpha and beta receptors
affinity
strength of the attraction between a drug and its receptor
Alzheimer’s disease (AD)
most common neurodegenerative condition of the brain; characterized by significant changes in brain tissue
apoptosis
programmed cell death prompted by a signal and designed to replace old cells with new ones
autoantibodies
produced by the immune system and are directed against one or more of the individual’s own cells, tissues, and proteins instead of foreign invaders
cholinergic receptors
mediate responses to acetylcholine; include muscarinic and nicotinic receptors
chronotropic
the increase or decrease of the heart rate
delusions
false, fixed beliefs not shared by others
diplopia
double vision—seeing two images of a single object
dysarthria
difficulty speaking because of muscle weakness
dysphagia
difficulty swallowing
hallucinations
perceiving something to be real in the absence of actual stimuli (visual, auditory, olfactory, gustatory, or tactile)
intrinsic activity
ability of a drug to activate a receptor upon binding
microtubules
components of a cell skeleton that provide structure and shape to cells, facilitate cell movement and cell division, and transport nutrients/substances within cells
myasthenia gravis (MG)
a progressive autoimmune neuromuscular disorder characterized by fluctuating muscle weakness and the onset of rapid fatigue
neurotoxic
drugs that alter the proper functioning of the nervous system
norepinephrine
neurotransmitter released by almost all of the postganglionic neurons of the SNS
parasympathetic nervous system (PSNS)
a division of the autonomic nervous system that carries the predominant tone in most organs with the exception of the blood vessels; responsible for the rest and digest functions
parasympatholytic
drugs that oppose the effects of the parasympathetic nervous system (also known as anticholinergic action)
parasympathomimetic
medications that activate the parasympathetic nervous system by mimicking the effects of acetylcholine
postganglionic neuron
neuron that goes from the ganglia to effector organs
preganglionic neuron
neuron that goes from the spinal cord to the ganglia and releases neurotransmitters
ptosis
drooping of the upper eyelid
remission
disappearance of the signs and symptoms of a disease
steady state
amount of drug eliminated equals the amount of drug within the circulation
Stevens-Johnson syndrome
hypersensitivity response to certain drugs characterized by lesions of the skin and mucous membranes, fever, malaise, and toxemia
sympathetic nervous system (SNS)
a division of the autonomic nervous system that is responsible for the fight-or-flight response
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