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Ways of prolongation of human life: previous / further
Normal age changes
Psychophysical
changes during a life make primary processes of ageing. We shall state
some of physiological and anatomic aspects of these processes now very
briefly. Traditionally
works of the last years are considered and proved, Usually
we considered, that the lost nervous fabric is never replaced and not
restored. Now we know, that the brain has some regenerative opportunities,
is especial at young organisms, and with age in some areas of a brain they
do not decrease. At regeneration there is a formation of new dendrids and
aksons (short and long shoots nejron, conducting nervous pulses from a
cell to a cell) and even sinapses (special image of the arranged contacts
between nervous cells). Thus, in due course one sites of a brain
degenerate, while others sites, on the contrary, are restored, keeping the
certain balance in a brain. But for deeper understanding of this
phenomenon the further researches are required. Speaking
about the main reason of ageing of a brain, doctors started with the
concept of "hardening of arterial vessels". This concept is
rejected now. Replacements to it are not present, and it is more than
questions, than answers. In a nervous fabric it is possible to speak about
one specific age change definitely. In a so-called black substance of an
average brain there is a gradual loss dofaminergical nejrons. If in these
nejrons it is not provided enough of the substance - transmitter there is
illness Parkinson. On the average at the 25-years person in a black
substance of a brain contains near 400000 dofaminergical nejrons, while at
80-years person their in 2 times has less. Reduction of number sinaptical
communications considerably reduces norm of redundancy to neural circuits.
It affects functioning of other systems of an organism. The researches
showed, that fall of the maintenance dofamin in a so-called striped body
of a brain is lower than 30 %-s' initial levels causes occurrence of
clinical symptoms of ageing. Such reduction dofamin connect also to
gradual decrease of speed of movement in the age of from 45 till 85 years.
Reasonable treatment of the reduced motor function is dofaminergical
therapy with which help in experiment the motor function at old animals is
restored or kept. Besides,
with age the lump of skeletal muscles, quantity of fast muscular fibres
and connected with them motonejrons, conducting nervous pulses to muscles
decreases. Apparently, it brings the contribution to decrease of impellent
speed. Thus, ageing is partly connected to easing functions of nervous -
muscular circuits and their atrophies... previous
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that the brain with the years degenerates. There is a loss nejrons, the
general atrophy develops, functioning mediator and sinaptic systems is
worsened. However last researches speak, what not all so is simple.
Undoubtedly, with age of function of a brain are worsened, but changes are
not general and not fatal. At some people in separate sites of a brain
nejrons are lost, for examples, a cerebellum and a bark of hemispheres,
but in other sites, we shall tell in olivs, loss nejrons does not occur in
general.
