Abdomen and Pelvis 
From this capsule, several septa penetrate the liver 
tissue, thus subdividing the organ into hepatic 
lobules. 
These lobules are polyhedral in shape and are composed of numer- 
ous liver cells which are radiallv arranged around the central vein 
(v. centralis), or venule of the hepatic vein {v. hepatica) (Fig. 5-22). 
Each lobule is surrounded at its edges by the portal triad, which is 
composed of a branch of the portal vein, a branch of the hepatic arterv 
(a. hepatica) and an interlobular bile ductule (ductulus biliferus) (Fig. 
5-23). Within the lobules, anastomosing sinusoids run from the portal 
to the central vein. Berv\-een these capillaries and the hepatic cells are 
found the spaces of Disse. 
5.5.2.5 Pancreas 
The pancreas produces enzvmes which break 
down lipids, carbohydrates and proteins. More- 
over, the pancreatic islets of Langerhans provide 
the body with insulin and glucagon, which plav an 
important role in the metabolism of carbohydrates. 
The pancreas is a rather large (up to 60 mm 
long) digestive gland of the "dendritic" type con- 
sisting of several elongated lobes (Fig. 5-24), 
which are inserted between various abdominal 
organs (Tables 11-1 Ic). Unlike the human pan- 
creas, no definite head. neck, bodv and tail can be 
distinguished in the hamster. The in situ pancreas 
is not visible in the superficial ventral aspect; it is 
covered by greater omentum and adipose tissue 
(Fig. 5-25). When the stomach is displaced caudo- 
ventrallv. the right lobe of the pancreas (lobus pan- 
creatis dexter) becomes visible (Fig. 5-26). This 
part extends along the greater curvature of the glan- 
dular stomach to the duodenum, occupving the en- 
tire space between the first duodenal flexure and the 
glandular stomach. K ing dextrocaudal to the papil- 
lary process of the liver. From this part of the pan- 
creas, a second portion extends within the duodeno- 
colic ligament from the second duodenal flexure to 
the ascending colon (Fig. 5-27). The third part of 
the pancreas becomes visible bv ventral displace- 
ment of the forestomach and spleen. This part oc- 
cupies the space between the spleen and the de- 
scending colon (Fig. 5-28). The pancreatic duct 
(ductus pancreaticus) discharges into the duodenum 
2 to 4 mm distal to the common bile duct. 
Histologicallv, the pancreas consists of two different tvpes of tissue, 
each of which represents an independent functional unit. The exocrine 
part consists of compound tubuloalveolar glands, while the endocrine 
part is represented bv the islets of Langerhans. which are composed of 
aggregated alpha-cells, beta-cells and D-cells ^Fig. 5-29). 
5.5.2.6 Spleen 
The spleen {lien) of the European hamster serves 
not onlv as a blood reservoir but also as a compon- 
ent of the lymphatic system. The color, consistency, 
size and weight of the spleen are dependent upon 
the age, nutritional status and sex of the hamster, 
and especiallv on the actual functional status of the 
organ. The spleen has an average weight of about 
229 mg for males and 209 mg for females; it is ap- 
proximately 34 mm long and 5 mm wide in both 
sexes (Tables 3,6). The spleen is located in the left 
hvpochondriac region and extends between the 
11th and 12th intercostal spaces (Fig. 5-25). It is 
dorsoventrallv disposed with its parietal surface 
(facies parietalis) adjacent to the dorsal and the left 
lateral abdominal walls; its dorsal end is slightly 
arched craniallv. while the ventral end inclines 
slightlv caudallv. This organ lies against the 
greater curvature of the forestomach, and is at- 
tached at the hilus ihilus liems) by the gastrosplenic 
ligament {lig. gastrolienale). The dorsal end {ex- 
tremitas dorsalis) presses against the left kidney, 
while the ventral end {extremitas ventralis) is bor- 
dered bv the junction of the transverse colon and the 
descending colon. The dorsal edge of the spleen is 
fixed to the left kidnev bv the lienorenal ligament. 
The color of this organ is reddish-purple in fixed 
specimens, and dark red in fresh-killed animals. 
Macroscopically in cut section, the spleen is red- 
dish-brown in color. It has a lanciform shape (Figs. 
5-30. 5-31 ) and, as a result of its prominent hilus, 
a triangular cross-section. 
In histological section, the serous coat and the fibroelastic capsule 
predominate. From this capsule originate the trabeculae, which pass 
into the spleen where thev branch and form the framework for the 
parenchvma. or red and white pulp (Fig. 5-32). Numerous ervthro- 
cvtes identify the red pulp (pulpa liems rubra), whereas the white pulp 
fpulpa lienis alba) is composed of dense Ivmphatic tissue which sur- 
rounds the small splenic capillaries and forms the splenic Ivmphatic 
follicles, the .\talpighian bodies. 
5.5.3 Craniomesocolic Vascularization 
and Innervation 
The aorta enters the abdominal cavity via the 
aortic hiatus of the diaphragm (Figs. 4-10, 4-11) 
and runs caudally along the left side of the spinal 
column and the medial edge of the left psoas major 
muscle (Fig. 5-33). Since the aorta lies dorsal to the 
abdominal space, running ventrally and applied to 
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