mesenteries Flashcards
the 4 boundaries of the abdominal cavity
- dorsal: lumbar vertebrae
- lateral & ventral: ribs and abdominal muscles
- caudal; pelvic inlet
- cranial; diaphragm
abdominal cavity extends well under the
costal arch
the thorax is defined caudally by the
margin of the ribs (although the thoracic cavity is defined caudally by the diaphragm)
part of abdominal cavity which is under the ribs is sometimes referred to as the
intrathoracic part of the abdominal cavity
The abdominal cavity and the cranial part of the pelvic cavity is lined by
peritoneum, a thin serous membrane
peritoneum is on wall is
peritoneum on organs is
parietal peritoneum
visceral peritoneum
space between the parietal peritoneum and visceral peritoneum is the
peritoneal cavity
(not so much a cavity as it is potential space, lubricated by fluid)
what is the potential space between the peritoneum and sublumbar muscles that lies dorsal to parietal peritoneum
retroperitoneal space
what abdominal organs lie dorsal to the peritoneum in the retroperitoneal space
aorta, caudal vena cava, kidneys and adrenal glands
what are the mesenteries
parietal peritoneum relfected down from dorsal wall of abdomen to support abdominal organs
describe the structure of the peritoneum
a thin serous membrane, a thin layer of squamous mesothelial cells overlying loose connective tissue, The mesothelial cells, which are specialized epithelial cells, have irregular microvilli and
are pinocytotic and phagocytic
serous membrane of peritoneum and mesenteries is lubricated with serous fluid, describe the serous fluid
- Similar to plasma, lower protein
- Free cells – lymphocytes, macrophages, etc. but NO red blood cells
peritonitis
inflammation of peritoneal cavity; volume of fluid and numbers of cell greater increase
in peritoneal effusions the free mesothelial cells may differentiate into fibroblast and lead to formation of
adhesions
septic peritonitis
infection of peritoneal cavity
what happens to the free fluid in peritoneal cavity in response to peritoneal effusions
the stoma is diaphragm aid in its reabsorption, its drained via lymphatic system
the embryonic digestive tract is supported by
the dorsal primitive mesentery and ventral primitive mesentery
during embryonic development the dorsal mesentery becomes _____
and the ventral mesentery becomes ____
dorsal mesentery –> greater omentum
ventral mesentery –> lesser omentum
what happens to the dorsal and ventral primitive mesenteries caudal to the stomach during development
ventral disappears
dorsal continues supporting role
mesenteries and omenta carry all the
blood vessels, nerves and lymphatic supplies for the digestive tract
the greater omentum is a fold of
serosa between dorsal body wall and greater curvature of stomach
the greater omentum contains
blood vessels, fat and lymphatic tissue (milky patches)
greater omentum play important part in
repair of damage to peritoneum (often placed next to surgery site to allow for repair and lymphatic drainage)
deep wall of greater omentum
originates of dorsal abdominal wall in region of pancreas and lies over the visceral surface of the stomach and towards the pelvis
The deep wall of the greater omentum originates on
the dorsal abdominal wall in the region of the pancreas, and lies over the visceral
surface of the stomach and towards the pelvis. Here it folds ventrally to become the
superficial wall, which runs back to the stomach (the part you see when you open the ventral abdomen)
omental bursa
the superficial and deep walls of the greater omentum form a sac; an enclosed pocket of peritoneal cavity
entry to the omental bursa sac is via
epiploic foramen (of winslow) between hepatic portal vein and caudal vena cava
** intestines can become caught in foramen
gastrosplenic ligament attaches
greater omentum to spleen
GDV
- gastric dilation volvulus
- stomach dilates due to food/gas
- stomach rotates in abdomen
- can drag spleen with it
- vascular compromise; blockage in blood supply to spleen and stomach
the lesser omentum is divided into what 2 ligament, where does it connect
- hepatogastric ligament; lesser curvature of stomach to visceral surface of liver
- heptaduodenal ligament; cranial part of duodenum to visceral surface of liver
the lesser omentum forms the ______ border of the
ventral border of the vestibule of the omental bursa
root of mesentery
short line of attachment of mesenteries to the dorsal abdominal wall, site of origin of the cranial mesenteric artery
site of origin of the cranial mesenteric artery
root of mesentery
what commonly occurs in the jejunal mesenteries
very large lymph nodes called the jejunal (mesenteric) lymph nodes
Which of the following forms the cranial border of the abdominal cavity?
diaphragm
The wall of the abdominal cavity is lined by the:
Parietal peritoneum
Which of the following organs lies in the retroperitoneal space?
A.
Stomach
B.
Liver
C.
Spleen
D.
Kidneys
Kidneys
Which of the following cell types should NOT be found in peritoneal fluid from a healthy animal?
A.
Lymphocytes
B.
Red blood cells
C.
Macrophages
D.
Mast cells
Red blood cells
As the stomach rotates during development, the dorsal primitive mesentary becomes which of the following?
Greater omentum
Which wall of the greater omentum do you see when you approach the abdominal cavity from the ventral aspect?
Superficial wall
The superficial and deep layers of omentum form a sac known as what?
The omental bursa
The stomach rotates during development. At the level of the stomach, the ventral primitive mesentery will become the:
Lesser omentum
The root of the mesenteries is the site of origin for the:
Cranial mesenteric artery
