130
2 Holographic Microscopy of Phase and Diffuse Objects …
obtained data, there emerge difficulties while trying to transfer the ascertained regularities to the whole organism, but there occurs a possibility to observe the process
under study on a simplified model directly during the hyperbary impact.
In a number of works, the preparations of Purkinje fibers [367], auricle muscle
[368] and a portal vein [369] were investigated. In these experiments, it was stated
that high hydrostatic pressure decelerates excitability distribution and reduces force
and frequency of contraction of a cross-striped muscle tissue as well as of a smooth
one. The data coincide with the results of studies of heart work by divers, which
was analyzed with ECG. The authors of the study interpret the obtained material as
an evidence of atrioventricular conduction decrease [370]. Observation of isolated
preparation of the right atrial auricle made it possible for the authors to assume
that long effect of helium-oxygen medium under high pressure modifies the primary
structure of slow sodium-potassium membrane canals and potassium canals that are
responsible for anomalous or inhibited rectification effect [371]. But it concerns
only long stays (32 days) of an organism under hyperbary. Under the impact of
high pressure on preparation of the excitable tissue, the true reaction mechanisms
are not clarified. It is possible that hydrostatic pressure not only modifies but also
directly influences the membrane processes, for example, potassium conductance
[372]. Also, it was fairly mentioned in the literature that under pressure there increases
the impact of the following factors on the isolated preparations: temperature [357]
and preparation survival medium [373]. In the works [15, 17], hyperbary impact on
neural and muscle fiber, lymphocytes, nerve and muscles was studied.
Thus, the analysis of the literature shows that processes occurring in tissues under
high pressure are not studied properly. However, it is theoretically possible that
a number of structure-functional changes can emerge, which are directly caused
by informational protein changes (framework and contractive cell proteins). Also,
changes in enzymatic systems of cell maintenance are assumed and, in some cases,
experimentally proved.
2.3.2 Holographic and Electrophysiological Study of Gas
Pressure Impact in the Range of 0:5 Atm.
on the Isolated Solitary Nerve Fiber
To influence a nerve, a solitary nerve or muscle fiber with high gas pressure in the
range of 0:5 atm. was placed in turn in a special camera, the schematic image of which
and its photo are shown in Fig. 2.28a, b. The cameras were made of stainless steel
in the form of two metal disks with a ring gasket made of vacuum rubber between
them. In the central part of both disks, optical windows were pasted with epoxy resin.
The windows were made of fused silica, the window thickness was 4 mm with the
diameter of 10 mm, and the deviation from the flatness does not exceed 10
.
2 Holographic Microscopy of Phase and Diffuse Objects …
obtained data, there emerge difficulties while trying to transfer the ascertained regularities to the whole organism, but there occurs a possibility to observe the process
under study on a simplified model directly during the hyperbary impact.
In a number of works, the preparations of Purkinje fibers [367], auricle muscle
[368] and a portal vein [369] were investigated. In these experiments, it was stated
that high hydrostatic pressure decelerates excitability distribution and reduces force
and frequency of contraction of a cross-striped muscle tissue as well as of a smooth
one. The data coincide with the results of studies of heart work by divers, which
was analyzed with ECG. The authors of the study interpret the obtained material as
an evidence of atrioventricular conduction decrease [370]. Observation of isolated
preparation of the right atrial auricle made it possible for the authors to assume
that long effect of helium-oxygen medium under high pressure modifies the primary
structure of slow sodium-potassium membrane canals and potassium canals that are
responsible for anomalous or inhibited rectification effect [371]. But it concerns
only long stays (32 days) of an organism under hyperbary. Under the impact of
high pressure on preparation of the excitable tissue, the true reaction mechanisms
are not clarified. It is possible that hydrostatic pressure not only modifies but also
directly influences the membrane processes, for example, potassium conductance
[372]. Also, it was fairly mentioned in the literature that under pressure there increases
the impact of the following factors on the isolated preparations: temperature [357]
and preparation survival medium [373]. In the works [15, 17], hyperbary impact on
neural and muscle fiber, lymphocytes, nerve and muscles was studied.
Thus, the analysis of the literature shows that processes occurring in tissues under
high pressure are not studied properly. However, it is theoretically possible that
a number of structure-functional changes can emerge, which are directly caused
by informational protein changes (framework and contractive cell proteins). Also,
changes in enzymatic systems of cell maintenance are assumed and, in some cases,
experimentally proved.
2.3.2 Holographic and Electrophysiological Study of Gas
Pressure Impact in the Range of 0:5 Atm.
on the Isolated Solitary Nerve Fiber
To influence a nerve, a solitary nerve or muscle fiber with high gas pressure in the
range of 0:5 atm. was placed in turn in a special camera, the schematic image of which
and its photo are shown in Fig. 2.28a, b. The cameras were made of stainless steel
in the form of two metal disks with a ring gasket made of vacuum rubber between
them. In the central part of both disks, optical windows were pasted with epoxy resin.
The windows were made of fused silica, the window thickness was 4 mm with the
diameter of 10 mm, and the deviation from the flatness does not exceed 10
.