Correlation of Parvalbumin Concentration with Relaxation Speed in Mammalian Muscles

• Published in: Proceedings of the National Academy of Sciences - PNAS 1982-12, Vol.79 (23), p.7243-7247
• Main Authors: Heizmann, Claus W., Berchtold, Martin W., Rowlerson, Anthea M.
• Format: Article
• Language: English
• Subjects: Animals; Biochemistry; Calcium - physiology; Denervation; Electrophoresis; Fast twitch muscle fibers; Gels; Guinea Pigs; Horses; Humans; In Vitro Techniques; Mice; Muscle Contraction; Muscle Denervation; Muscle Proteins - physiology; Muscle Relaxation; Muscles; Parvalbumins - physiology; Rats; Skeletal muscle; Time Factors
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.79.23.7243

The physiological role of the Ca2+-binding protein parvalbumin in skeletal muscle has been investigated by measuring the parvalbumin content by HPLC in a variety of mammalian muscles, including man, and comparing the results with the respective muscle relaxation properties and fiber type compositions. The parvalbumin concentrations were highest in the skeletal muscles of the smallest animal investigated (mouse, gastrocnemius: 4.9 g/kg), which has the highest relaxation speed, and lowest in the larger animals (horse, deep gluteal muscle: ≤ 0.001 g/kg) and man (vastus, triceps: ≤ 0.001 g/kg), which have much lower relaxation speeds. Analysis of three type-homogeneous muscles of the guinea pig revealed highest parvalbumin concentrations (0.25 g/kg) in sartorius (type IIB) and lowest concentrations (≤ 0.007 g/kg) in soleus (type I), consistent with the different half-relaxation times of fast and slow muscles. Denervation of the rat extensor digitorum longus, which increases the half-relaxation time from 9.4 to 19 msec, resulted in a 20% decrease of the parvalbumin content. Given this close correlation between parvalbumin content and relaxation speed in a variety of muscles and species, we suggest that parvalbumin is involved directly in the relaxation process in fast muscles.