Autonomic Nervous System

The ANS consists of the parasympathetic Nervous System and the Sympathetic Nervous System. The impulses are all efferent to the effector tissue. The Parasympathetic Nervous System stimulates the rest and digests response. The cranial nerves associated with it are the Oculomotor nerve III, Facial Nerve VII, Glossopharyngeal Nerve IX, and the Vagus nerve X. There are two neurons in ANS pathways, Preganglionic neurons and postganglionic neurons, to the effector tissues. Preganglionic neurons of the ANS always release the neurotransmitter Ach. In the Parasympathetic division they have long axons, and the postganglionic neurons also release Ach and have short axons. Preganglionic neurons of the Sympathetic division are short, and postganglionic neurons are long and release Norepinephrine or epinephrine. The Adrenal medulla is part of the Sympathetic division but the postganglionic neurons release Epinephrine, Norepinephrine, and dopamine directly into the blood stream. These neurotransmitters bind to Muscarinic receptors on the effector tissue. These are secondary messenger systems and are found in the membrane of Cardiac Muscle cells, Smooth Muscle cells, and glands.

I was diagnosed with IBS last year due to a prolonged period of cronic diarrhea. I did have all the symptoms of IBS but I noticed when I was on vacation the symptoms went away and the medicine they gave me did nothing. So I believe this was due to prolonged high levels of stress. When we talked about cortisol levels being high with long term stress it made wonder if cortisol could cause that.