These nerves are susceptible to injury either from trauma to the abdomen or from surgical laceration. Such an injury would result in the weakening of the muscles of the abdominal wall, as well as pain and tenderness in that area. Weakening of these muscles can lead to difficult bending the body at the waist and in some cases, difficulty breathing. If the injury to one of these nerves is in the inguinal region, the muscle weakness that results can make the person more likely to develop an inguinal hernia (to be discussed in next section).
The Peritoneum is a serous membrane that both lines the abdominopelvic cavity and the surrounds most of the organs in the cavity. It is composed of two layers, the parietal peritoneum and the visceral peritoneum. The parietal peritoneum is the outer layer, which layers the interior of the abdominal wall. The visceral peritoneum covers the organs in this intraperitoneal cavity. Both layers are composed of simple squamous epithelial cells. The space between the two layers is known as the peritoneal cavity, and it is filled with peritoneal fluid, which contains mostly water and electrolytes. The peritoneal fluid lubricates the visceral layer, and reduces the friction between organs when they move around (e.g. digestion).
The peritoneum and associated organs can protrude through a hole in the abdominal cavity, a condition known as an abdominal hernia or inguinal hernia (depending on location of hole). There are two types of inguinal hernia, direct and indirect. Direct hernias protrude through the superficial inguinal ring (picture on the left), while the indirect hernias protrude through the deep inguinal ring. Such herniation occurs more often in males, with about 86% of inguinal hernias consisting of spermatic cord protrusion into the inguinal canal. An additional contributing factor to the heightened incidence in males is the weakness of the pelvic wall relative to that of females. Muscles weakness in the abdominopelvic cavity, especially in the inguinal region, can be attributed to nerve damage, which will make the individual more prone to herniation (as described in above section). These type of hernias can be corrected surgically if need be, in an operation called a hernioplasty.
The gastric mucosa is a membrane that lines the stomach and is covered in a mucous layer that protects the stomach's outer surface from the acid housed in the organ. It is made up of simple columnar epithelium. Throughout the mucosa there are indentations known as gastric pits, which is where the gastric glands are found.These gastric pits contain the three important secretory cells of the stomach: the mucosa cells, the chief cells, and the parietal cells. The mucosa cells produce mucus, the chief cells secrete pepsin, and the parietal cells secrete hydrochloric acid. The mucus plays an important role in protecting the lining of the stomach, while the pepsin and hydrochloric acid are important for digestion and killing of ingested microbes (Hcl).
Gastric ulcers can occur when there is a lesion in the mucosal lining of the stomach. Such a condition can usually be accredited to one of two sources, a bacterial infection or an overproduction of stomach acid. The majority of such ulcers are associated with Helicobacter pylori, a bacterium that can survive the extreme acidity of the stomach. The other cause may be that the subject produces too much hydrochloric acid, which overwhelms the mucosal lining, leading to erosion. These two agents make each other more effective in that one can wear down the mucosa making it more vulnerable for the other to damage it further. In severe cases, the gastric arteries can be perforated, which could result in a fatal outcome. The vagus nerve controls the secretion of the HCl from the parietal cells, so the medical approach to chronic gastric ulcers are to perform a surgical sectioning of the nerve, along with removing the eroded tissue.
References
Moore et al. "Clinically Oriented Anatomy" (2010) 6th ed
http://academic.amc.edu/martino/grossanatomy/site/Medical/CASES/GI/pop%20ups/appendicitis%20anspop_up7.htm
http://humanbodydisease.com/peptic-ulcer-251.html
http://www.nytimes.com/imagepages/2007/08/01/health/adam/17075Inguinalhernia.html
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