Instruction manual

SI-MT/SI-MKB/SI-HTB
WORLD PRECISION IN STRU MENTS
11
the shorter sarcomeres superimposed on the lines of the longer sarcomeres. This provides
a qualitative method for judging how much the sarcomeres get disordered during a
contraction. Broadening of the sarcomere distribution indicates increased sarcomere
disarray. Often this is not reversible and indicates loss of sarcomere integrity and reduced
viability of the muscle preparation. Reduction in peak force and simultaneous increased
resting tension can then be further indication of a dying muscle; the preparation needs to
be replaced.
NOTE: Often it is important to keep the sarcomere length constant, as opposed to the
total length of the preparation, during an isometric contraction. If, for instance, if the
muscle is fi xed with its tendons, the muscle contraction elongates the tendons. Even
though the distance between the ends of the muscle is kept constant, the muscle
contraction effects an internal shortening of the sarcomeres of the muscle. In order to get
isometric contractions of the muscle, the sarcomere length must be kept constant during
the contraction. In this case, the output signal of the camera is used with additional
feedback system electronics to control the linear motor position. The feedback system
controls the linear motor so that the sarcomere length is held constant. This is referred
to as sarcomere clamping and is implemented in the SI-COLU constant load unit. With
this unit, clamping can be around force, overall muscle length and sarcomere length in
tonically contracting striated muscle.
Front Panel
WARNING: DO NOT EXPOSE YOUR EYES TO LASER LIGHT. EVEN REFLECTED
LASER LIGHT MAY BE HARMFUL. ALWAYS WEAR PROTECTIVE LENSES WHEN
WORKING WITH LASERS.
USB Port
Configuration
Buttons
LCD Display
Laser Connection
Camera Connection
Analog Outputs
Laser Intensity
Sync Output
Video Output
Fig. 13 SI-SARCAM Sarcomere Spacing Module