shaped to allow the collection of the
efluate for reperfusing, perfusing the
next tissue or bioassay analysis. The
isometric force transducer is fixed on
the rod using a Vernier control.
is installed in the main superfusion
chamber. The holder can easily be
removed to simplify the preparation.
The holder consists of the body, the
hook for fixing the tissue, the stainless
steel cannulas for superfusion and the
stimulation electrodes. The tissue is
attached using a thread to the tissue
hook. The thread at the other end of the
tissue must be attached to the
transducer. A slide in the holder body
allows easy positioning of the thread in
the central hole. The superfusion
cannulae can be rotated in the main
and the thread fixed to the transducer. The stimulation electrodes are made of
platinum and must be buckled to be close to the tissue. The electrodes do not
touch the tissue but must be parallel and close enough to the tissue so that the
superfusing solution makes electrical contact.
tube connected to a thermocirculator.
solution or solution containing the test compound. The outcoming solution is
collected and goes to waste or is stored for later bioassay analysis.
outcoming solution after superfusion is collected and used for superfusing
again in the same tissue.
all the subsequent tissues are superfused with the outcoming solution of
the preceding chamber.
Vernier control, bridge amplifier for the force transducer, Data acquisition
ACAD, electrical stimulator, thermocirculator if heat exchangers are used.
involving the study of contraction and relaxation of smooth muscle
preparations, the effect of drugs that interfere with these actions, as well as
those that interfere with autonomic neurotransmission. The system consists
of a main stand that can receive up to eight single superfusion chambers.
Each chamber is equipped with electrical stimulation capability, a rod for
fixing the force transducer and an optional two channel heat exchanger. The
lower end of the tissue is held by a stainless steel hook. The thread attached
to the top of the tissue passes through the opening directly to the force
transducer. The superfusion solution is fed by a peristaltic pump through a
stainless steel cannula to the thread; it runs down the thread and superfuses
the tissue. Two separate solution paths are available for superfusion with
and without test substance. Two platinum wires are placed parallel to the
tissue to form stimulation electrodes. The solution running down provides
electrical contact between the electrodes and the tissue.
thermostating owing to the low thermal conductivity of the material. The
chamber is fixed on the frame in the horizontal position. All additional parts
(tissue holder, dual heat exchanger, road for mounting the transducer) are
fixed on the chamber. The upper part of the chamber receives the tissue
holder. The lower part can be swung away to simplify access to the