title: Amphipaths differentially modulate membrane surface deformation in rat peritoneal mast cells during exocytosis.
abstract: OBJECTIVE
  Salicylate and chlorpromazine exert differential effects on the chemokine release from mast cells. Since these drugs are amphiphilic and preferentially partitioned into the lipid bilayers of the plasma membranes, they would induce some morphological changes in mast cells and thus affect the process of exocytosis.
  
  
  METHODS
  Employing the standard patch-clamp whole-cell recording technique, we examined the effects of salicylate and chlorpromazine on the membrane capacitance (Cm) during exocytosis in rat peritoneal mast cells. Using confocal imaging of a water-soluble fluorescent dye, lucifer yellow, we also examined their effects on plasma membrane deformation of the cells.
  
  
  RESULTS
  Salicylate dramatically accelerated the GTP-γ-S-induced increase in the Cm immediately after its application, whereas chlorpromazine significantly suppressed the increase. Treatment with salicylate increased the trapping of the dye on the cell surface, while treatment with chlorpromazine completely washed it out, indicating that both drugs induced membrane surface deformation in mast cells.
  
  
  CONCLUSIONS
  This study demonstrated for the first time that membrane amphipaths, such as salicylate and chlorpromazine, may oppositely modulate the process of exocytosis in mast cells, as detected by the changes in the Cm. The plasma membrane deformation induced by the drugs was thought to be responsible for their differential effects.
authors: Department of Physiology I, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Miyagi, Japan.
authors: Itsuro
authors: I
authors: Kazama
authors: Yoshio
authors: Y
authors: Maruyama
authors: Sara
authors: S
authors: Takahashi
authors: Takashi
authors: T
authors: Kokumai
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002462:Cell Membrane / Q000502:physiology; D002478:Cells, Cultured; D002746:Chlorpromazine / Q000494:pharmacology*; D005089:Exocytosis / Q000187:drug effects*; D005456:Fluorescent Dyes / Q000737:chemistry; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D007546:Isoquinolines / Q000737:chemistry; D008297:Male; D008407:Mast Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects; D018613:Microscopy, Confocal; D018408:Patch-Clamp Techniques; D010529:Peritoneal Cavity / Q000166:cytology; D051381:Rats; D017208:Rats, Wistar; D012980:Sodium Salicylate / Q000494:pharmacology*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D005456:Fluorescent Dyes; D007546:Isoquinolines; D016244:Guanosine 5'-O-(3-Thiotriphosphate); C017475:lucifer yellow; D002746:Chlorpromazine; D012980:Sodium Salicylate