Physiology 1021 Lecture Notes - Lecture 16: Autonomic Nervous System, Postganglionic Nerve Fibers, Urinary Bladder

• School: Western University
• Department: Physiology
• Course: Physiology 1021
• Professor: John Ciriello

Document Summary

The ans plays a huge role in maintaining homeostasis, which involves a dynamic balance between the two divisions of the ans; the sympathetic (sns) and the parasympathetic (psns) nervous systems. The ans not only involves a motor component (sns and psns), but an afferent component as well. This sensory section is used to adjust the amount of motor control exerted by either the. The main morphological characteristic of the peripheral component of the ans is that it uses 2 neurons, a pre- ganglionic and a post- ganglionic neuron. A ganglion is cell bodies of post-ganglionic cells. All pre-ganglionic cells are myelinated, and they all release ach. One of the main differences between psns and sns is that the post-ganglionic neuron releases ach in the psns while the post-ganglionic neuron releases noradrenaline in the sns. The adrenal medulla is only innervated by the sns preganglionic fibres (only 1 neuron). The preganglionic axon innervates chromaffin cells and release ach.