Parasympathetics Part 2 (vagus) Flashcards
Where are preganglionic parasympathetic cells of the vagus nerve located?
posterior (dorsal) nucleus of the vagus
T/F: the vagus supplies parasym info to the kidneys and suprarenal glands.
False; pretty much all other thoracic and abdominal viscera though
Where are postganglionic parasym fibers of the vagus nerve located usually?
in the organs supplied or the blood vessels that supply the organ
T/F: myocardium, submucosal plexus, and myenteric plexus all contain postganglionic cells from the vagus.
True
Preganglionic from the vagus to the heart are carried in which nerves?
superior and inferior cardiac nerves
Where do fibers from the vagus nerve which travel to the heart synapse?
in the cardiac plexus at the basse of the heart and wall of the heart
Where are postganglionic fibers (from the vagus to the heart) carried specifically?
sinoatrial node, atrioventricular node, and the atrioventricular bundle to reach subendocardial branches (Purkinje fibers)
What effect will parasympathetic impulses have on the myocardium and coronary arteries?
inhibit myocardium and constrict coronary arteries
What kind of parsym fibers are carried in anterior and posterior bronchial branches?
preganglionic fibers (from vagus to lungs)
Where do bronchial branches synapse?
in the pulmonary/bronchial plexus surrounding the bronchial tree
Where do postganglionic fibers from the pulmonary plexus go?
these reach the bronchial musculature and bronchial glands
What effect do parasym impulses have on the bronchial tree and bronchial glands? consider asthmatics
constiction of bronchial tree and increases secrretions of bronchial glands
How do preganglionic fibers from the vagus get to the esophagus?
carried in recurrent laryngeal nerves as well as the anterior and posterior esophageal branches
Where do preganglionic fibers from the vagus to the esophagus synapse specifically?
in the wall of the esophagus
What do postganglionic fibers from the vagus to the esophagus supply specifically?
smooth muscle fibers of the esophagus
What part of the esophagus is composed of skeletal muscle? what nerve supplies these muscle fibers?
upper 1/3;
recurrent laryngeal nerve
Which vagal trunk usually has more branches (preganglionic parsym) to the stomach, anterior or posterior?
posterior (about 6), anterior has bout 4
Where do preganglionic fibers from the vagus to the stomach synapse?
submucosal (Meissner’s) and myenteric (Auerbach’s) plexuses in the wall of the stomach
Where do postganglionic fibers from the plexuses around the stomach go to and supply?
smooth muscle fibers
What effect does parasym stimulation have on the smooth muscle and gastric juices of the stomach?
contraction of muscles, increases secretion of gastric juices
Preganglionic fibers from the vagus to the small intestines, cecum, appendix, an colon make their way here via what structure?
posterior vagal trunk
What plexus do fibers from the vagus nerve use to get to the duodenum?
celiac plexus
Preganglionic fibers from the posterior vagal trunk that do not travel through the celiac plexus reach their destinations by using what plexuse?
superior mesenteric plexus
Where do preganglionic fibers from the vagus synapse while traveling to the SI, cecum, appendix, and colon?
submucosal and myenteric plexuses, as with the stomach
From the submucoal and myenteric plexuses, fibers travel where?
smooth muscle fibers of associated organs
What effect does parasym stimulation have on smooth muscle and intestinal glands?
contracts smooth muscle and is secretomotor for intestinal glands
What type of visceral afferents are asscoiated with the vermiform appendix?
nociceptors
Preganglionic parasym fibers from the hepatic branch of the right vagal trunk reach what structures?
gall bladder, pancreas, and biliary tree
Where do preganglionic fibers from the vagus to the gall bladder, pancreas and biliary tree synapse specifically?
muscular walls of gall bladder and biliary tree and in the glandular tissue of the pancreas
What effect does parasym stimulation have on smooth muscle in the gall bladder and biliary vessels? in pancreatic glands?
increases smooth muscle activity;
secretomotor for pancreatic glands
How do preganglionic fibers reach the spleen from the posterior vagal trunk?
via splenic plexus
What is the splenic plexus an extension of?
celiac plexus
How do preganglionic fibers reach the kidneys from the posterior vagus?
renal plexus
T/F: the motor supply to the kidneys is strictly parasympathetic.
False; strictly sympathetic. Therefore, any fibers reaching the kidney via parsym pathways are likely visceral afferents
T/F: all of the preganglionic parasym fibers to the liver come from the anterior vagal trunk.
False; most from anterior, but some are from the posterior vagal trunk
What extension of the celiac plexus do preganglionic fibers use to reach the liver?
hepatic plexus
T/F: like the kidneys, parasym supply to the liver is likely primarily efferent.
False; should say primarily afferent
T/F: Similar to the liver and kidneys, vagal supply to the suprarenal glands is afferent and those fibers are carried in the posterior vagal trunk.
True
