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Physiological Recordings of High and Low Output NMJs on the Crayfish Leg Extensor Muscle
Published on: November 17, 2010
Na+-Ca2+ exchange in plasma membranes of crayfish striated muscle
M Ruscák1, J Orlický, M Juhászová
1Centre of Physiological Sciences, Slovak Academy of Sciences, Bratislava, Czechoslovakia.
Abstract:
Na+-Ca2+ exchange rates and some physico-chemical properties of the exchanger were studied in crayfish striated muscle membranes enriched in plasma membranes prepared by differential centrifugation of muscle microsomal fraction on discontinuous sucrose density gradient. The lightest subfraction with the highest Na+, K+-ATPase and Mg2+-ATPase activities also showed the highest Na+-Ca2+ exchange rates. A number of physico-chemical characteristics of the Na+-Ca2+ exchanger found in the present experiments were similar to those reported for excitable membranes of mammals, except for the temperature optimum (20 degrees C for the crayfish).
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