Peripheral Receptors Flashcards
Depolarization
Necessary to reach AP. Na rushes into the cell, makes the inside more positive. Allows transmission
What does resting potential look like?
Negative inside membrane, positive outside
Repolarization
Return to resting. K leaves the cell and the inside becomes negative. Cell cannot transmit another impulse until back to resting.
Cerebrum
Higher functioning, learning, memory, lots of sensory input amd interpretation
Thalamus
Relay center for impulses from spinal cord, brainstem, and cerebellum to cerebral cortex. Pain interpretation
Hypothalamus
Link between nervous and endocrine system. Pituitary control
Medulla
Brainstem. Important and vital physiological activity. Relay sensory info between spinal cord and brain
Reticular formation
Starts in medulla, up through brainstem. RAS system responsible for wakefulness, arousal and sleep cycles
Elements and function of PNS
Soinal nerves, cranial nerves. Connect CNS with glands, muscles, and effectors
Somatic NS
Skeletal muscle, voluntary, efferent from CNS to skeletal muscle
ANS
Involuntary, from CNS to carsiac muscle, smooth muscle, and glands
Where do cell bodies for symp and ps preganglionic neuron originate
Sym thoracolumbar cord
Ps craniosacral cord
Ganglion
Where axon of first neuron synapses with dendrites of the second neuron
Where does axon of second neuron synapse
Target tissue
Ganglion location in parasympathetic neurons?
Ganglions close to effector organs
Which three tissues only have sympathetic inner ation?
Adrenal medulla, sweat glands, and hair follicles
What do these ganglia supply: Ciliary Sphenopalatine Otic Celiac Superior mesenteric Inferior mesenteric
Ciliary eye
Sphenopalatine eye
Otic parotid gland
Celiac bottom of stomach, spleen, adrenal gland, kidney, small intestine
Superior mesenteric small intestine
Inferior large intestine, urinary bladder
Somatic nervous system NT(s)?
ACH. 1 neuron system
ANS preganglionic neurons release
ACH
Parasympathetic postganglionic neurons release
ACH
Sympathetic postganglionic neurons release
Epinephrine or norepinephrine
Talk about the adrenal medulla
It only has sympathetic innervation. it has a LONG preganglionic neuron, which releases ACH and the adrenal medulla acts like a postganglionic neuron and releases epinephrine or norepinephrine directly into the bloodstream
What does the autonomic nervous system innervate
Cardiac muscle, smooth muscle, and glands
Acetylcholine is the neurotransmitter always released in which system
Parasympathetic nervous system
What anatomical feature causes the sympathetic nervous system to have short preganglionic neuron’s and long postganglionic neuron’s
Sympathetic trunk
Where does the preganglionic neuron synapse
Ganglion
Name five places cholinergic receptors are found
Cardiac muscle, smooth muscle, gland, neuromuscular junction, autonomic ganglia, adrenal Medulla
Parasympathetic effects at the AV node? Atrial muscle?
Decreased conduction speed at the AV node. atrium muscle relaxes and decreases contractility
Parasympathetic affects on airflow and secretions
Decrease airflow and stimulate secretion
Parasympathetic affect at vascular smooth muscle?
It INDIRECTLY decreases blood pressure by removing sympathetic stimulation when you decrease one drive, you increase the other
Parasympathetic affects at the internal urethral sphincter?
There is only sympathetic drive at the internal urethral sphincter. PS works by removing sympathetic drive, influencing it indirectly
Internal urethral sphincter?
Only sympathetic. Decreased sympathetic drive allows it to open
What is unique about sweat glands?
They only have sympathetic innervation and they have muscarinic receptors despite that fact
Where are muscarinic receptor found? What effects do they have?
Muscle. Heart muscle, smooth muscle, secretory glands. The muscles can excite or relax. The secretory glands can also be either excitatory or inhibitory
Where are nicotinic receptors found? What kind of affects do they have?
Everywhere else. The adrenal medulla, autonomic ganglia, neuromuscular junction, somatic nervous system (skeletal muscle). Always excitatory
Name three adrenergic neurotransmitters
Dopamine, epinephrine, norepinephrine
What kind of receptors are important in kidney vasculature?
Dopaminergic receptors
In which nervous systems are alpha-1 and alpha-2 adrenergic receptors found?
Alpha-1 is found in the autonomic nervous system. Alpha-2 is found in the central nervous system
Where are beta-1 adrenergic receptors found? What are their effects?
The heart and kidneys. Their effects are excitatory. They increase HR, conduction speed, contraction force. They also stimulate renin release
Where are beta-2 adrenergic receptors found? What are their effects
Skeletal blood vessels, bronchioles, G.I. smooth muscle. Their effects are inhibitory. They cause dilation and relaxation
Where are dopaminergic receptors found? What are their effects?
Kidney, heart, mesenteric blood vessels. They cause dilation
Where are alpha-1 receptors found? What are their Effects
Arterioles, urethra, Eye, sphincters. They cause constriction of the arterioles and sphincters. Increased urethral tone. Pupil dilation
Where are alpha-2 receptors find? What are their effects
Presynaptic neuron’s and skeletal muscle vessels. Their effects are inhibitory. They cause constriction
What FX do epinephrine and norepinephrine have at beta-2?
Norepinephrine has no significant effect at beta-2. Epinephrine is a very potent stimulator of beta-2
What effects do epinephrine and norepinephrine have at alpha-1 and beta-1
They equally stimulate alpha-1 and beta-1
How do indirect acting cholinergic agents work?
They inhibit acetylcholine breakdown. This increases the amount of acetylcholine available to bond and cause parasympathetic affects
What does the suffix lytic mean
To antagonize. For example parasympatholytic would mean to antagonize cholinergic receptor or produce effects opposite of cholinergic (sympathetic)
What does contraindication mean
Do not use. Any condition which makes a particular type of treatment improper or dangerous
Name some clinical uses of cholinergic agents
Diagnose myasthenia gravis, decrease intraocular pressure in glaucoma, stimulate GI motility, treat urinary retention, stimulate micturition, control vomiting, antidote for neuromuscular blockers
What do direct acting cholinergic agonists do
Interact with and stimulate cholinergic receptors. They have high affinity and high efficacy
