[Functional role of parvalbumins in regulating Ca2+ in the contraction--relaxation cycle of vertebrate skeletal muscles].

On the basis of parvalbumin property to change Ca2+-binding constant within the pH-region from approxim-tely 7 to approximately 8 a hypothesis that parvalbumins are pH-regulated Ca2+-depot in muscles has been stated. The addition of parvalbumin to native actomysin complex at pH approximately 7 in the presence of ATP and Ca2+ results in partial inhibition of its superprecipitation. The change of pH up to approximately 8 leads to the restoration of actomyosin superprecipitation.