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
Artigo
em Inglês
| 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.
Texto completo:
DisponíveL
Índice:
LILACS (Américas)
Assunto principal:
Técnicas In Vitro
/
Cafeína
/
Soroalbumina Bovina
/
Bloqueadores dos Canais de Cálcio
/
Canais de Cálcio
/
Trifosfato de Adenosina
/
Neurotransmissores
/
Músculo Esquelético
/
Fibras Musculares Esqueléticas
/
Estimulantes do Sistema Nervoso Central
Tipo de estudo:
Estudo prognóstico
Limite:
Humanos
Idioma:
Inglês
Revista:
Braz. j. med. biol. res
Assunto da revista:
Biologia
/
Medicina
Ano de publicação:
1997
Tipo de documento:
Artigo
/
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