Bovine serum albumin potentiates caffeine - or ATP - induced tension in human skinned skeletal muscle fibers
Braz. j. med. biol. res
;
30(5): 675-8, May 1997. ilus, graf
Article
in English
| LILACS
| ID: lil-196682
RESUMO
Human skinned muscle fibers were used to investigate the effects of bovine serum albumin (BSA) on the tension/pCa relationship and on the functional properties of the Ca2+- release channel of the sarcoplasmic reticulum (SR). In both fast-and slow-type fibers, identified by their tension response to pSr 5.0, BSA (0.7-15 muM) had no effect on the Ca2+ affinity of the contractile proteins and elicited no tension per se in Ca2+-loaded fibers. In contrast, BSA (>1.0 muM) potentiated the caffeine induced tension in Ca2+-loaded fibers, this effect being more intense in slow-type fibers. Thus, BSA reduced the threshold caffeine concentration required for eliciting detectable tension, and increased the amplitude, the rate of rise and the area under the curve of caffeine-induced tension BSA also potentiated the tension elicited in Ca2+-loaded fibers by low-Mg2+ solutions containing 1.0 mM free ATP. These results suggest that BSA modulates the response of the human skeletal muscle SR Ca2+-release channel to activators such as caffeine and ATP.
Full text:
Available
Index:
LILACS (Americas)
Main subject:
In Vitro Techniques
/
Caffeine
/
Serum Albumin, Bovine
/
Calcium Channel Blockers
/
Calcium Channels
/
Adenosine Triphosphate
/
Neurotransmitter Agents
/
Muscle, Skeletal
/
Muscle Fibers, Skeletal
/
Central Nervous System Stimulants
Type of study:
Prognostic study
Limits:
Humans
Language:
English
Journal:
Braz. j. med. biol. res
Journal subject:
Biology
/
Medicine
Year:
1997
Type:
Article
/
Project document
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