Ch. 6 Nervous System pt. 5

Somatic Nervous System vs. Autonomic Nervous system
-their effector organs & movement of neuron signals?

Somatic- voluntary

effector organ: Skeletal muscle
-1 neuron to effector organ

Autonomic- involuntary

effector organs: smooth and cardiac muscles, glands, blood vessels

-CNS→preganglionic neuron→ganglion→postganglionic neuron→effector organs(2 neuron pattern)

2 divisions under the autonomic nervous system? What do they do & what neurotransmitters do each division release?

1) Sympathetic Division→”fight or flight”

-AcH at the preganglionic neurons
-NE at the postganglionic neurons (Epi mostly in adrenal medulla)

2) Parasympathetic Divison→”rest or digest”
-Ach at BOTH pre- & post- ganglionic neurons

Serotonin is a CNS neurotransmitter. Where are serotonergic cell bodies concentrated in the brain?

raphe nuclei of the brainstem

Parasympathetic & Sympathetic divisions are also known as?

Parasympathetic→craniosacral division
sympathetic→thoracolumbar division

what is the difference in length of the pre- and postganglionic neurons in the parasympathetic & sympathetic divisions?

parasympathetic→ long preganglionic neuron & short postganglionic neuron]

sympathetic→short preganglionic neuron & long postganglionic neuron

We know the Somatic NS system relates to skeletal muscle fibers. When somatic neurons release AcH, what kind of receptors do they bind to on the skeletal muscle?

Nicotinic Receptors

In the parasympathetic division, what type of receptors does AcH bind to?

Ach binds to Nicotinic receptors at the ganglion, but a muscarine receptor at the target organ

in the sympathetic division, what type of receptors does AcH bind to?

Ach binds to Nicotinic receptors at the ganglion, but NE bind to Adrenergic receptors at the target organ

Explain the role Adrenal Medulla in the Sympathetic Nervous system

Preganglionic neuron releases AcH to nicotinic receptors on the Adrenal Medulla.

Adrenal Medulla then releases 80% Epi & 20% NE into the blood →Adrenergic receptors on target organs
(Epi and NE in this case are HORMONES)

what are the 2 types of Beta Blockers? What do they do?

1) Propanolol

2) Atenolol

(both decrease heart rate BUT Propranolol has side effect of causing bronchoconstriction)

dual innervation

examples?

organs receive effects from both parasympathetic & sympathetic nervous system

1) Antagonistic effects (heart rate)
2) Complementary(salivary gland secretion)

3) Cooperative (urination)