  We study relationship between the physical quantities that characterize
pion-nucleon and nucleon-nucleon interaction on the basis of the fact that
nuclear forces in the nucleon-nucleon system at low energies are mainly
determined by the one-pion exchange mechanism. By making use of the recommended
proton-proton low-energy scattering parameters, we obtain the following value
for the charged pion-nucleon coupling constant g$_{\pi ^{\pm }}^{2}/4\pi
=14.55(13)$. Calculated value of this quantity is in excellent agreement with
the experimental result g$_{\pi ^{\pm }}^{2}/4\pi =14.52(26)$ of the Uppsala
Neutron Research Group. At the same time, the obtained value of the charged
pion-nucleon coupling constant differs markedly from the value of the neutral
pion-nucleon coupling constant g$_{\pi ^{0}}^{2}/4\pi =13.55(13)$. Thus, our
results show considerable charge splitting of the pion-nucleon coupling
constant.
