194
Dynamics
of
the Vascular System
arteioles and venules are close to
90".
Capillaries, in general, are
running parallel next to perfusing muscle or tissues. These are well
illustrated by the photomicrographs of Smaje et al. (1970) in the
cremaster muscle of the rat (Fig. 7.1.2) and also by Zweifach et al.
(1
974) in the cat omentum (Fig. 7.1.3).
Fig.
7.1.2:
Photomicrograph
of
rat cremaster muscle showing pattern
of
vascular
structure. Y-shaped and T-shaped branching junctions are common, in addition to cross-
connections
of
the vessels.
From
Smaje et
al.
(1970).
A
bat (a flying mammal) wing and the mesenteric bed
of
a small
mammal are popular preparations for studying blood flow in the
microcirculation. The flow into the capillaries has been shown
to
remain
