ANAT autonomics of the head neck neurogenic bladder Flashcards
what area in the brainstem is responsible for the baroreceptor reflex and maintenance of blood pressure
rostral ventrolateral medulla
four bilateral parasympathetic nuclei
where are they
edinger-westphal (CN III – midbrain)
superior salivatory nucleus (CN VII – pons)
inferior salivatory nucleus (CN IX – medulla)
dorsal nucleus of the vagus nerve (CN X – medulla)
lesions of the light reflex
CN II
CN III
CN II - impair both ipsilateral and contralat reflex
CN III - large dilated pupil in ipsilat. eye
which ganglion do superior salivatory nucleus send fibers to
sphenopalatine ganglion –> lacrimal gland
submandibular ganglion –> submandibular and sublingual gland
which ganglion do inferior salivatory nucleus send fibers to
otic ganglion –> parotid salivary gland
causes of horner’s (3)
central lesion
focal lesion on lateral brainstem/upper cervical spinal
cord
preganglionic lesion
damage sympathetic chain
tumor on apex of lungs
postganglionic lesion
compressed in internal artery dissection
mass lesions in cavernous sinus
what is the baroreceptor reflex for
prevents fluctuations of arterial blood pressure due to changes in body posture, physical activity, or emotional state
orthostatic hypotension - decrease in arterial pressure from standing up from seated or lying down position
what innervates carotid baroreceptors
what innervates aortic baroreceptors
CN IX
CN X
aortic arch ONLY responds to increases in BP
where do baroreceptors send their signals to
nucleus solitarius of medulla –> nucleus ambiguous
two roles of nucleus ambiguus
baroreceptor reflex
send inhibitory signals to the SA node of the heart –> bradycardia
send inhibitory signals to the rostral ventrolateral medulla –> inhibit sympathetic vasomotor activity –> vasodilation –> lower BP
baroreflex afferent failure
what causes
what consequence
damage to carotid sinus, aortic arch, nuclus solitarius/ambiguous, rostral ventrolateral medulla
fluctuation hypertension
baroreflex efferent failure
what causes
what consequence
damage to efferent sympathoexcitatory pathway
orthostatic hypotension
what is responsible for prevention of voiding
what m
sympathetics
through both sacral splanchnic and hypogastric n
relax detrusor
contract internal urethral sphincter
what is responsible for voiding
what m
parasympathetics
pelvic splanchnic n
contract detrussor
relax internal urethral sphincter
what two things must occur for micturition to occur
excitatory signals are sent to activate sacral parasympathetic nucleus
inhibitory signals are sent to inhibit the Onuf nucleus
