2.5 Results and Conclusions
161
of recording a hologram or a holographic interferogram of a nerve trunk in the
transmitted as well as in the reflected light was experimentally shown. The obtained
holograms make it possible to judge about structural and phase peculiarities of these
objects.
For the first time, the refraction structure (of the refractive index profile) of intravital myelinated nerve fibers was studied on the created experimental sample of the
transflective holographic interference microscope. There were obtained interferograms of the fibers with the diameter of ~10 μm and spatial resolution of more than
1 μm, and the interference fringe frequency, which is one order higher than the fringe
frequency in a classic interference microscope.
On the nerve fiber interferograms, the myelin sheath in different shape variations
could be easily observed. In the center of the nerve fiber area, the perikaryon of
Schwann’s cell with the nucleus is situated. In the interferograms, it is seen that the
most significant band movement is observed in the axial area of the fiber and the
myelin sheath. This band movement is conditioned by the cylindrical shape of the
fiber and a significantly higher refractive index of lipoprotein structures of the myelin
sheath in comparison with the environment.
The software was created to calculate the radial distribution of the refractive index
(in this case the nerve fiber) of axially symmetric phase objects. There was developed
and implemented as a software one of the most prospective deciphering algorithms
of holographic interferograms, namely, the Abel inversion algorithm based on the
approximation of experimental data by cubic spline-functions with boundary conditions corresponding to interference fringe alterations. Radial distribution of nerve
fiber refractive index was calculated.
A fundamental result is experimentally measured for the first time the refractive
index distribution of intravital myelinated nerve fibers with the electrophysiological control. The result was obtained using the developed by the author and the
co-workers holographic interference microscopy method and the transflective holographic microscope with the spatial frequency of the interference fringes, which is
one order higher than the fringe frequency in a classic interference microscope.
The radial distribution of the refractive index of Schwann’s sheath and the myelinated nerve fiber axon were studied. The obtained values of the refractive index
of myelin (1.44) and axoplasm (1.36) correspond to the native state of these structures in the fiber. The experimentally measured rather high for biological structures
value of the refractive index of the nerve fiber myelin sheath (1.44 ± 0.01) matches
morphological data about the thick package of the protein-lipoid membranes of this
structure. The changes of the axoplasm on the fiber axis are much bigger than on the
areas directly under the myelin sheath. It is ascertained that the dependence character of the refractive index on the radius of the internodal area of the myelinated
nerve fiber is similar to the profile changes of the refractive index of separate optical
waveguides.
The refractive index distribution of Schwann’s sheath and the axoplasm of the
myelinated nerve fiber is analogous to the refractive index distribution in the tubular
optical fiber, and the muscle fiber is a perfect diffractive grating, a splitter and a light
energy re-distributor as it occurs in optical waveguide communication lines. This
161
of recording a hologram or a holographic interferogram of a nerve trunk in the
transmitted as well as in the reflected light was experimentally shown. The obtained
holograms make it possible to judge about structural and phase peculiarities of these
objects.
For the first time, the refraction structure (of the refractive index profile) of intravital myelinated nerve fibers was studied on the created experimental sample of the
transflective holographic interference microscope. There were obtained interferograms of the fibers with the diameter of ~10 μm and spatial resolution of more than
1 μm, and the interference fringe frequency, which is one order higher than the fringe
frequency in a classic interference microscope.
On the nerve fiber interferograms, the myelin sheath in different shape variations
could be easily observed. In the center of the nerve fiber area, the perikaryon of
Schwann’s cell with the nucleus is situated. In the interferograms, it is seen that the
most significant band movement is observed in the axial area of the fiber and the
myelin sheath. This band movement is conditioned by the cylindrical shape of the
fiber and a significantly higher refractive index of lipoprotein structures of the myelin
sheath in comparison with the environment.
The software was created to calculate the radial distribution of the refractive index
(in this case the nerve fiber) of axially symmetric phase objects. There was developed
and implemented as a software one of the most prospective deciphering algorithms
of holographic interferograms, namely, the Abel inversion algorithm based on the
approximation of experimental data by cubic spline-functions with boundary conditions corresponding to interference fringe alterations. Radial distribution of nerve
fiber refractive index was calculated.
A fundamental result is experimentally measured for the first time the refractive
index distribution of intravital myelinated nerve fibers with the electrophysiological control. The result was obtained using the developed by the author and the
co-workers holographic interference microscopy method and the transflective holographic microscope with the spatial frequency of the interference fringes, which is
one order higher than the fringe frequency in a classic interference microscope.
The radial distribution of the refractive index of Schwann’s sheath and the myelinated nerve fiber axon were studied. The obtained values of the refractive index
of myelin (1.44) and axoplasm (1.36) correspond to the native state of these structures in the fiber. The experimentally measured rather high for biological structures
value of the refractive index of the nerve fiber myelin sheath (1.44 ± 0.01) matches
morphological data about the thick package of the protein-lipoid membranes of this
structure. The changes of the axoplasm on the fiber axis are much bigger than on the
areas directly under the myelin sheath. It is ascertained that the dependence character of the refractive index on the radius of the internodal area of the myelinated
nerve fiber is similar to the profile changes of the refractive index of separate optical
waveguides.
The refractive index distribution of Schwann’s sheath and the axoplasm of the
myelinated nerve fiber is analogous to the refractive index distribution in the tubular
optical fiber, and the muscle fiber is a perfect diffractive grating, a splitter and a light
energy re-distributor as it occurs in optical waveguide communication lines. This