Involvement of HPC-1/syntaxin-1A antigen in transmitter release from PC12h cells.
We examined the effect of antiserum against HPC-1/Syntaxin-1A on the norepinephrine release from digitonin-permeabilized PC12h cells. PC12h cells were permeabilized with digitonin and preincubated with nonimmunized serum or antiserum against HPC-1. The release of norepinephrine was measured in the presence or absence of calcium. The calcium-dependent norepinephrine release was increased in the cells preincubated with anti HPC-1 antiserum. However, with a higher concentration of anti HPC-1 antiserum, the calcium-dependent norepinephrine release was decreased, possibly because of a nonspecific effect. In the case of purified IgG, the same results were obtained. These findings suggested that HPC-1 plays an important role in the exocytosis of transmitter presumably by suppressing the membrane fusion process between the synaptic vesicle and presynaptic membrane.
Kushima
Y
Y
2nd Department of Physiology, Kyorin University, School of Medicine, Tokyo, Japan.
Fujiwara
T
T
Morimoto
T
T
Akagawa
K
K
D000704:Analysis of Variance; D000818:Animals; D000906:Antibodies / Q000494:pharmacology*; D000911:Antibodies, Monoclonal; D000954:Antigens, Surface / Q000276:immunology / Q000502:physiology*; D015153:Blotting, Western; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D002118:Calcium / Q000494:pharmacology; D002462:Cell Membrane / Q000737:chemistry / Q000502:physiology / Q000648:ultrastructure; D002463:Cell Membrane Permeability; D004072:Digitonin; D007074:Immunoglobulin G / Q000494:pharmacology; D007150:Immunohistochemistry; D007700:Kinetics; D008561:Membrane Fusion; D009414:Nerve Growth Factors / Q000494:pharmacology*; D009419:Nerve Tissue Proteins / Q000276:immunology / Q000502:physiology*; D009638:Norepinephrine / Q000378:metabolism*; D016716:PC12 Cells; D051381:Rats; D013572:Synaptic Vesicles / Q000502:physiology; D050827:Syntaxin 1
D000906:Antibodies; D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D007074:Immunoglobulin G; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; C494213:Stx1a protein, rat; D050827:Syntaxin 1; D004072:Digitonin; D002118:Calcium; D009638:Norepinephrine