Ca-release Channel of the Sarcoplasmic Reticulum of the Snake (Reptile) Skeletal Muscle = 뱀 (파충류) 골격근 소포체 칼슘유리 채널

다국어 초록 (Multilingual Abstract)

To investigate properties of Ca-release channel in the reptile skeletal muscle, electrophoretical analysis, purification of RyR, $[^3H]ryanodine$binding study, and $^{45}Ca-release$ were carried out in the SR vesicles prepared from the snake skeletal muscle. The snake SR vesicle has the single high molecular weight protein band on SDS-PAGE, and its mobility was similar with that of rat skeletal SR vesicles. The high molecular weight band on SDS-PACE was found in the $[^3H]ryanodine$ peak fractions $(Fr_{5-7})$ obtained from the purification step of the RyR. Maximal binding site and Kd of the snake SR RyR were 6.36 pmole/mg protein and 17.62 nM, respectively. Specific binding of $[^3H]ryanodine$ was significantly increased by calcium and AMP (P<0.05), but not or slightly inhibited by tetracaine, ruthenium red (5.4%), or $MgCl_2$ (21%). $^{45}Ca-release$ from the SR vesicles loaded passively was significantly increased by the low concentration of calcium $(1{\sim}10{\mu}M)$ and AMP (5 mM)(P<0.05), but significantly decreased by the high concentration $(300{\mu}M)$ of calcium, tetracaine (1 mM), ruthenium red $(10{\mu}M)$, and $MgCl_2$ (2 mM)(P <0.05). From the above results, it is suggested that snake SR vesicles also have the RyR showing the similar properties to those of mammalian skeletal RyR with the exceptions of no or slight inhibition of $[^3H]ryanodine-binding$ by tetracaine, ruthenium red, or $MgCl_2$.