In vitro binding of dantrolene to sarcoplasmic reticulum of rabbit skeletal muscle.
Dantrolene upon binding to microsomes containing sarcoplasmic reticulum of rabbit thigh muscle exhibits a fluorescence with emission at 490 nm, which shows a blue shift of 35 nm compared with its fluorescence in ethylacetate. Using fluorescence techniques, dantrolene binding to microsomes isolated from rabbit thigh muscle was investigated. From Scatchard plots of binding studies, the association constant (Kass) and the number of binding sites of dantrolene to sarcoplasmic reticulum were calculated, which was found to be 9.6 X 10(4) M-1 and 1.71 mumole/g of membrane proteins, respectively. In the presence of verapamil (1.25 X 10(-4) M), another calcium antagonist, the binding of dantrolene to microsomes was enhanced. However, at a high concentration of verapamil (3.75 X 10(-4) M), the Scatchard plot of dantrolene binding was found to be biphasic.
D000818:Animals; D003620:Dantrolene / Q000378:metabolism*; D005260:Female; D005453:Fluorescence; D066298:In Vitro Techniques; D008297:Male; D009132:Muscles / Q000378:metabolism*; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*; D014700:Verapamil / Q000494:pharmacology
D014700:Verapamil; D003620:Dantrolene