Download Peritoneum and Peritoneal Folds

Peritoneum and Peritoneal Folds
The peritoneum is the largest serous membrane in the body and lines
the abdominal cavity. The tissue has several components including the
the mesothelium and an underlying supporting areolar connective tissue
layer. The connective tissue in turn has two layers: the parietal
peritoneum, which lines the abdominal wall, and the visceral
peritoneum, which covers some organs and serves as their serosae.
The peritoneal cavity is the small space between the parietal and
visceral peritoneum that contains the lubricating serous fluid.
The peritoneum includes large folds that bind organs to each other and
to the abdominal walls. This keeps the organs in the proper place and
suspends them when we are upright. Within these folds are blood
vessels, lymphatic vessels, and nerves that innervate the abdominal
organs.
The Five Major Peritoneal Folds
Fold
Description
Comment
Greater
omentum
Drapes over the transverse colon and
small intestine
High adipose tissue content vastly
expands with weight gain, creating
the characteristic "beer belly"
Falciform
ligament
Attaches the liver to the anterior
abdominal wall and diaphragm
The liver is the only digestive organ
attached to the anterior abdominal
wall
Lesser
omentum
Suspends the stomach and duodenum
from the liver
Provides a pathway for the blood
supply of liver; contains the common
bile duct
Mesentery
Attaches the jejunum and ileum of the
small intestine to the posterior
abdominal wall
Includes blood and lymphatic vessels,
and lymph nodes
Mesocolon
Attaches the transverse colon and
sigmoid colon of the large intestine to
the posterior abdominal wall
Along with mesentery, it holds
intestines loosely in place, enabling
movement with muscle contractions
EXAMPLE
Homeostatic Imbalances of the
Peritoneum: Peritonitis
Inflammation of the peritoneum is called peritonitis. It can be caused by
an injury that penetrates into the abdomen or from an ulcer that
perforates the stomach wall, allowing gastric fluids into the peritoneal
cavity. The most common cause of peritonitis is a ruptured appendix.
The appendix is a terminal part of the cecum (a peritoneal pouch at the
beginning of the large intestine), and the function (if any) is still debated.
When the appendix bursts open, bacteria-laden feces spurt into the
peritoneum. Usually, the peritoneal layers will bind together around the
site of inflammation, keeping the infection from spreading, while
macrophages move in to dispose of infected tissue. Peritonitis that
spreads out into the peritoneal cavity can be life threatening. Surgically
removing the infected tissue and administering high doses of antibiotics
treat the condition. Generally, peritonitis is a concern with any kind of
puncture wound to the abdomen.