Autonomic nervous system overview

Autonomic nervous system overview

1. Sympathetic: The "Fight or Flight" response

   • Increased HR and BP
   • Pupil dilation
   • Inhibits salivation
   • Dilates bronchioles
   • Inhibits digestion
   • Increased glucose
     • Peripheral vasoconstriction
       • Relaxed bladder
         • Ejaculation and orgasm
   • Norepinephrine
     • Group called catecholamines
     • Target organ receptors called adrenergic receptors
       • Alpha and beta receptors (pg 147)
     • Broken down by monoamine oxidase
   • Epinephrine
     • Adrenal gland most responsible for release
     • Activates alpha and beta receptors, but has an affinity for beta
     • Terminated through hepatic metabolism

2. Prasympathetic: The "Rest and Digest" response

   • Constricts pupils
     • Stimulates salivation
       • Slows heart rate, decreases contractility
         • Constricts bronchioles
           • Stimulates digestion
             • Stimulates gallbladder function
               • Contracts bladder
                 • Stimulates erection and lubrication
                   • Decreased HR and BP
   • Acetylcholne
     • Cholinergic nerves RELEASE Ach. Their receptors are:
       • Nicotinic- Located at the ganglionic synapse in parasympathetic and sympathetic NS
         • Located in a lot of places, including skeletal muscle
         • Activation causes tachycardia, hypertension, and increased tone and motility in digestive tract
         • Very little clinical use
       • Muscarinic- Located on target tissues affected by postganglionic neurons in parasympathetic NS
     • Broken down by acetylcholinesterase (AchE