Unit 3- Autonomic Nervous System Flashcards
Somatic Innervation
One neuron with cell body in CNS and myelinated axon extending to muscle
Autonomic Innervation
Preganglionic neuron in CNS and unmyelinated slow conducting postganglionic neuron extending to body structure
General Visceral Efferents
Sympathetic, parasympathetic, and enteric nervous systems
Sympathetic Nervous System
Short preganglionic axons leaving spinal cord in thoracolumbar region, passing through ventral root to the sympathetic ganglion chain
Parasympathetic Nervous System
Long preganglionic axons leaving spinal cord in cranial and sacral regions to synapse in ganglia within viscera
Intramural Ganglia
Ganglia residing close to or within pelvic viscera
Enteric Nervous System
GI sensory and motor interneurons that function independently of, but can still be influenced by, the CNS, NANC fibers
Dual ANS Innervation
Both parasympathetic and sympathetic innervation that is functionally antagonistic, but weighted towards PSNS or SNS
Sympathetic ONLY Organs
Adrenal medulla, peripheral blood vessels, pilomotor muscles, sweat glands
Adrenal Medulla
Modified sympathetic ganglion with chromaffin cells analogous to neurons with nicotinic receptors
Chromaffin Cells
Synthesize and EPI and NE in the blood
Sympathetic Preganglionic NT
Ach
Nicotinic Neuronal Receptors
Bound and activated by Ach on postganglionic neurons
Cholinergic Fibers
Synthesize and release Ach
Postganglionic Cholinergic Fibers
Postganglionic sympathetic neurons that release Ach to bind to muscarinic receptors
Postganglionic Sympathetic NT
NE
Adrenergic Receptors
α and β receptors bound and activated by NE
Adrenergic Fibers
Nerve fibers that synthesize and release NE
Dopamine
Immediate metabolic precursor to NE, released by some postganglionic sympathetic neurons to bind dopaminergic receptors in peripheral vasculature
Preganglionic Parasympathetic NT
Ach
Postganglionic Parasympathetic NT
Ach
Muscarinic Receptors
Bound and activated by postganglionic Ach
Renal Vessel Sympathetic Receptors
Dopaminergic