slide set 4.4

  1. Autonomic nervous system
    • innervate cardiac muscle
    • smooth muscle
    • most exocrine glands and some endocrine glands
    • 2 neuron chian
  2. postganglionic neurons in the sympathetic division
    • an axon may synapse with post ganglionic neurons in the ganglion t first reaches for
    • an axon may continue, without, synapsing, through the synaptic trunk ganglion
  3. cranial flow
    • preganglionic fibers run via:
    • Oculomotor nerve (3)
    • facial nerve (7)
    • glassopharyngeal nerve (9)
    • vagus nerve (10)

    • cell bodies located in cranial nerve nuclei in the brain stem
  4. outflow in the vagus nerve
    • fibers innervate visceral organs of the thorax and most of the abdomen
    • stimulates - digestion reduction in heart rate and blood pressure
    • Preganglionic neutrons cell bodies
    • located in dorsal motor nucleus in the medulla
  5. sympathetic vs parasympathetic
    • SNS = promote fight or flight response
    • PNS = dominates in quiet, relaxed situations
    • 75% of all impulse travel along the vagus nerve ( cranial nerve 10)
  6. anatomical differences in SNS and PNS
    • 1. Length of postgangliotic fibres
    • SNS = long fibres
    • PNS = short fibers

    • 2. Branching of axons
    • SNS = highly branched
    • influences many organs
    • PNS = few branches
    • localized effect
  7. Neurotransmitters of ANS
    • Neurotransmitter released by the pregangliotic axons
    • Ach = for both branches (cholinergic)

    • Neurotransmitter released by postgangliotic axons
    • SNS = most release noreepinepherine (adrenergic)
    • PNS = release Ach
  8. receptors
    • For Ach, nicotinic receptors exist on all autonomic ganglia
    • Muscarinic receptors = exist on all effector cells membranes
    • For NE and EPI = alpha and beta receptors
  9. adrenergic receptors
    • Alpha receptors
    • A1= contraction of genitouitary smooth muscle
    • Ga= activates phospholipase C
    • IP3 and DAG
    • <Ca++> = ↑ contractions

    • A2 = contraction of vascular smooth muscle
    • Gi = ↓ cAMP


    • Beta receptors
    • B1= effects the heart
    • B2=smooth muscle
    • B3= lipolysis in adipose tissue
Author
K.A
ID
324703
Card Set
slide set 4.4
Description
phys
Updated