functional organization Flashcards
symapthetic nerves receive what info from where? via?
afferent info from the targets they innervate. via spinal, supraspinal, local reflexes.
general principle: correlation between positions of neurons and target?
correlation between rostrocaudal position of spinal preganglionic neurons and rostrocaudal position of target
general principle: specificity?
specific groups of cells in autonomic ganglia project to specific peripheral targets
general principle: individual ganglion cells receive what inputs?
one dominant input from one spinal segment, and other weaker subthreshold inputs from about four adjacent segments
general principle: nuclei in where connect to what for what main effect
nuclei in medulla/brainstem/hypothalamus connect to all sympathetic ganglia via sympathetic preganglionic neurons in nuclei in the intermediolateral cell column of the spinal cord = enables coordinated discharge of symp NS
general principle: certain nuclei from where connect to? why?
certain nuclei in medulla/brainstem/hypothalamus have connections to specific peripheral ganglia to enable localized and directed sympathetic discharge
sympathetic vs para: what spinal segments
symapthetic = thoracic and lumbaer. para = cranial and sacral
symp vs. para: size of pre/post ganglions
sympathetic: short preganglionic, long post. para = long pre, short post because ganglia close to targets
two main places where symp ganglia found
paravetebral sympathetic ganglia, prevertebral symapthetic ganglia
sympathetic: preganglionic neurons in where? (3)
thoracic and lumbar spinal cord: in lateral horn aka IML or intermediolateral cell column, central autonomic nucleus, and intercalated nucleus
preganglion neurons: receptors?
high ratio of NMDA to kainate/AMPA receptors
preganglionic sympathetic: axons synpase onto what 3 places
one or more ganglion cells in one or more paravertebral sympathetic ganglia. pass through paravertebral, synpse in ganglion cells in prevertebral sympathetic ganglia. pass through paravetebral then synapse in chromaffin cells in the adrenal medulla and SIF cells in ganglia.
chromaffin cells: ratio of NA:A? also contain?
NA:A 30: 70. also contain enkephalin, NPY, somatostatin, neurotensin, GABA
NA and A chromaffin cells may be innervated by? adrenaline/NA release triggered by what two things?
innervated by different groups of spinal preganglionic neurons. adrenaline: hypoglycemia. NA: fall in BP
sympathetic ganglion cells/post ganglionic nerves release NA except in what 2 places? what do they have instead
muscarinic cholinergic sympathetic fibers: in eccrine (thermoregulatory) sweat glands. blood vessels within skeletal muscle (cats and dogs, not humans)
eccrine glands as ooposed to?
eccrine = thermoregulatory. as opposed to apocrine glands innervated by noradrenergic sympathetic nerves.
paravertebral sympathetic ganglia
superior and inferior cervical ganglion. stellate ganglion. thoracic, lumbar and sacral ganglia.
prevertebral/preaortic ganglia include:
celiac ganglia. superior mesenteric ganglia (solar plexus). inferior mesenteric aka hypogastric ganglion
ganglia of the pelvic plexus aka ? includes?
previsceral or terminal ganglia. mixed sympathetic and parasympathetic ganglia + short adrenergic neurons
visceral afferents: 3 roles
activate autonomic reflexes. convey visceral sensation to CNS. neurogenic inflammation
visceral afferents: local axon reflexes involving what propagation
antidromic propagation (aka backwards)
triple response of Lewis (ex to what?) involves what 3 things
ex to insect bite: localized red spot. brighter red flush or flare develops more slowly. wheal that replaces red spot (edema)
triple response of Lewis: flare is due to?
stimulation of sensory nerves by histamine produces release of substance P, CGRP, ATP
triple response of Lewis: flare produces what 4 things, aka what
neurogenic inflammation / axon reflex: vasodilation, plasma protein extravasation, mast cell degradnulation, lymphocyte granulocyte macrophage activation
