Avtor/Urednik     Chowdhury-Haque, Helena; Popoff, Michel R; Zorec, Robert
Naslov     Actin cytoskeleton depolymerization with Clostridium spiroforme toxin enhances the secretory activity of rat melanotrophs
Tip     članek
Vir     J Physiol
Vol. in št.     Letnik 521, št. 2
Leto izdaje     1999
Obseg     str. 389-95
Jezik     eng
Abstrakt     1. We measured membrane capacitance (Cm) in cultured rat melanothrops pretreated with Clostridium spiroforme toxin (CST), which spacifically depymerises cartical filamentous actin (F-actin). Phalloidin staining confirmed that CST treatment depolymerised the F-actin. 2. In controll cells, cytosol dialysis with 1 microM Ca(i)2+ incrreased Cm by 23+-4% (n=11) relative to the resting Cm 400 s after the start of patch rupture. In CST-treated cells the increase in Cm was 32+-5% (n=15), not significantly different from controls. The rate of Cm increase was affected transiently by CST treatmentr, peaking at 1 min after patch rupture. The maximal rate of cm increase was 4.27 +- 0.85 fFs-1 (n=12; measured 200 s after the start of patch rupture) in controls and 8.0 +- 1.35 fFs-1 (n=23; measured 75 s after th estart of patch rupture) in CST-treated cells (p<0.01). 3. In control cells cytosol dialysis with 0 microM Ca(i)2+ decreased Cm by 9+-3% (n=7), in CST treated cells Cm increased by 11+-3% (n=7) relative to resting Cm 400 s after the start of cytosol dialysis. The rate of change in Cm remained constant (controls: -1 to -2 fFs-1; CST treatment: 1-2 fFs-1). (Abstract truncated at 2000 characters.)
Deskriptorji     PITUITARY GLAND
CLOSTRIDIUM
BACTERIAL TOXINS
CYTOSKELETON
ACTINS
RATS, WISTAR
PATCH-CLAMP TECHNIQUES
CYTOSOL
CELLS, CULTURED
MICROSCOPY, FLUORESCENCE
TIME FACTORS