Muscle Spindle: Encoding
M. Chua & C. C. Hunt, Physiology UNC, Chapel Hill NC.

The Sensory Region of a Muscle Spindle.

spin_ci2.gif (77729 bytes)An isolated muscle spindle stained with the antibody.  Serial optical sections have been taken at 1 um steps on a Leica TCS-NT confocal microscope.  The sarcolemma of the intrafusal muscle fibres are clearly labelled while the sensory endings, which wrap around the intrafusla fibres, remain unlabelled.  Some labelling of myelin around the axon, which innervate the sensory endings, can be discerned.  This may be non-specific labelling.  Click on this image to display a large rotating rendered view (4.8 MBytes) of the spindle.   The two bands on either side of the fibres are part of the capsule.


Nodes of Ranvier on a Motor Axon

AxonNodeZ4nnAaB.jpg (32448 bytes)
Motor axons showing nodes of Ranvier stained with the antibody.  The mid internodal region displayed less intense and less concentrated labelling.

The Neuromuscular Junction.

A neuromuscular (motor) junction close to the spindle shown above.   The post synaptic membrane is labelled.  Post junctional folds can be seen. Labelling of the junction above with AP1351 (Syntrophin).  Syntrophin co-locallizes with the antibody.  Some additional presynaptic staining is present.

Above images superimposed.  Green is the antibody and red is AP1351.   No cross talk was detected during sequential scanning.

Images may not be used without permission (c) copyright 1998 M. Chua