scholarly journals Coupling between fast and slow inactivation revealed by analysis of a point mutation (F1304Q) in mu 1 rat skeletal muscle sodium channels.

1996 ◽  
Vol 494 (2) ◽  
pp. 411-429 ◽  
Author(s):  
H B Nuss ◽  
J R Balser ◽  
D W Orias ◽  
J H Lawrence ◽  
G F Tomaselli ◽  
...  
1996 ◽  
Vol 494 (2) ◽  
pp. 431-442 ◽  
Author(s):  
J R Balser ◽  
H B Nuss ◽  
N Chiamvimonvat ◽  
M T Pérez-García ◽  
E Marban ◽  
...  

1999 ◽  
Vol 515 (1) ◽  
pp. 61-73 ◽  
Author(s):  
John P. O'Reilly ◽  
Sho-Ya Wang ◽  
Roland G. Kallen ◽  
Ging Kuo Wang

2000 ◽  
Vol 524 (1) ◽  
pp. 37-49 ◽  
Author(s):  
Zhenhui Chen ◽  
Boon‐Hooi Ong¹ ◽  
Nicholas G. Kambouris ◽  
Eduardo Marbán ◽  
Gordon F. Tomaselli ◽  
...  

Biochemistry ◽  
1987 ◽  
Vol 26 (24) ◽  
pp. 7546-7556 ◽  
Author(s):  
Xiaotao Guo ◽  
Akira Uehara ◽  
Arippa Ravindran ◽  
Shirley H. Bryant ◽  
Sherwood Hall ◽  
...  

1998 ◽  
Vol 1373 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Jean-François Desaphy ◽  
Annamaria De Luca ◽  
Paola Imbrici ◽  
Diana Conte Camerino

1998 ◽  
Vol 275 (6) ◽  
pp. C1465-C1472 ◽  
Author(s):  
Jean-François Desaphy ◽  
Annamaria De Luca ◽  
Diana Conte Camerino

Although the skeletal muscle sodium channel is a good substrate for cAMP-dependent protein kinase (PKA), no functional consequence was observed for this channel expressed in heterologous systems. Therefore, we investigated the effect of 8-(4-chlorophenylthio)adenosine 3′,5′-cyclic monophosphate (CPT-cAMP), a membrane-permeable cAMP analog, on the native sodium channels of freshly dissociated rat skeletal muscle fibers by means of the cell-attached patch-clamp technique. Externally applied CPT-cAMP (0.5 mM) reduced peak ensemble average currents by ∼75% with no change in kinetics. Single-channel conductance and normalized activation curves were unchanged by CPT-cAMP. In contrast, steady-state inactivation curves showed a reduction of the maximal available current and a negative shift of the half-inactivation potential. Similar effects were observed with dibutyryl adenosine 3′,5′-cyclic monophosphate but not with cAMP, which does not easily permeate the cell membrane. Incubation of fibers for 1 h with 10 μM H-89, a PKA inhibitor, did not prevent the effect of CPT-cAMP. Finally, the β-adrenoreceptor agonist isoproterenol mimicked CPT-cAMP when applied at 0.5 mM but had no effect at 0.1 mM. These results indicate that cAMP inhibits native skeletal muscle sodium channels by acting within the fiber, independently of PKA activation.


Sign in / Sign up

Export Citation Format

Share Document