[Verse 1] Thoracolumbar fibers, T1 through L2 Preganglionic short, postganglionic shoots through Paravertebral chains where the synapses form Norepinephrine flooding like an electrical storm Alpha one constricts the vessels, beta one speeds the heart Beta two dilates the bronchi, let's take it apart Adrenal medulla skips a step — chromaffin cells release Epinephrine straight to blood, no ganglion in between [Chorus] SLUD for parasympathetic — Salivation, Lacrimation Urination, Defecation — craniosacral origination Fight or flight is sympathetic, acetylcholine preganglionic Postganglionic norepinephrine — alpha, beta, supersonic Muscarinic, nicotinic — remember where each one sits Nicotinic at the ganglion, muscarinic after it [Verse 2] Cranial nerves three, seven, nine, and ten Vagus nerve is wandering the viscera again Short preganglionic, long postganglionic fiber Sacral roots S2 through S4 — the pelvic plexus provider ACh binds the muscarinic, M2 slows the SA node M3 contracts the gut wall, opens up the glandular road Atropine blocks the muscarinic — heart rate climbing, pupils wide Glycopyrrolate can't cross the blood-brain barrier — keep that centralized [Chorus] SLUD for parasympathetic — Salivation, Lacrimation Urination, Defecation — craniosacral origination Fight or flight is sympathetic, acetylcholine preganglionic Postganglionic norepinephrine — alpha, beta, supersonic Muscarinic, nicotinic — remember where each one sits Nicotinic at the ganglion, muscarinic after it [Verse 3] At the neuromuscular junction, motor nerve terminal dips Voltage-gated calcium channels open, acetylcholine ships Quanta released into the cleft, diffuses to the fold Nicotinic alpha subunits bind — the end-plate threshold's crossed and bold Sodium rushes, potassium exits, action potential ignites Acetylcholinesterase hydrolyzes fast, resets the synaptic sites Choline gets recycled back, choline acetyltransferase Loads the vesicle again — a beautifully efficient chase [Bridge] Burns and denervation spread the receptors out Extrajunctional nicotinic receptors, gamma subunit throughout Succinylcholine hyperkalemia — potassium pours from every pore Immobility creates the same — resistance to non-depolarizers, plus more Fade on tetanus — train-of-four ratio reveals the depth Post-tetanic potentiation — calcium mobilized, a transient breath Phase two block with succinylcholine overdose starts to look like non-depol Monitoring your twitches tells you where you are in the protocol [Chorus] SLUD for parasympathetic — Salivation, Lacrimation Urination, Defecation — craniosacral origination Fight or flight is sympathetic, acetylcholine preganglionic Postganglionic norepinephrine — alpha, beta, supersonic Muscarinic, nicotinic — remember where each one sits Nicotinic at the ganglion, muscarinic after it
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