Abstract:
There are conflicting opinions about the splenic microcirculation in mammals,
specifically whether it is a closed or open type. The cardiovascular system of the
Lyleis flying fox was used for this study. Vascular corrosion cast technique with
SEM (Scanning Electron Microscope) was applied to this investigation. Fifteen
adult Lyleis flying foxes (Pteropus lylei) of both sexes, weighing between 300 and
450 g. were used. It was revealed that the spleen received the main arterial supply
from the splenic and short gastric arteries. These arteries entered the spleen at the
hilum and divided into many trabecular branches, which pass along trabeculae.
Each trabecular artery branched into central or white pulp arteries, that are
eccentrically situated in the white pulp. Along their courses in the white pulps, the
central arteries gave off small branches supplying the white pulps. Then, these
arteries passed into the red pulp and ramified into many small penicillar arterioles,
that nourished the white and red pulps as well as marginal zones. The termination of
these arterioles directly connected into the red pulp sinusoids that emptied the blood
into the pulp venules. The pulp venules proceeded to the trabecular and splenic
veins, respectively. It is most likely that splenic circulation of the Lyleis flying fox
is a closed type of blood circulation