Vasoactive intestinal peptide enhances phorbol myristate acetate-induced chemiluminescence in human lymphocytes.
Phorbol-myristate-acetate (PMA) induced in lymphocytes the production or reactive oxygen intermediates in a process which was stimulated by the presence of vasoactive intestinal peptide (VIP) in a dose-dependent response at VIP concentrations in the range 10(-11)-10(-8) M. The dissociation constant for the high-affinity receptors of VIP agreed with the ID50 of the activation of adenylate cyclase, and the ID50 for the stimulation by VIP of PMA-induced chemiluminescence, which were close to 0.2 nM VIP. Forskolin produced in lymphocytes an effect quite similar to VIP. A comparison of the response to VIP and forskolin of lymphocytes and monocytes showed that, in contrast to forskolin, VIP failed to induce the above described effect in monocytes. A possible mechanism involving protein kinase C, which is activated by PMA, and an intracellular signal linked to VIP receptors is pointed out. This study further supports a role for VIP as a mediator in the neuroimmune system.
Lopez-Gonzalez
M A
MA
Departamento de Bioquímica Médica y Biología Molecular, Hospital Universitario Virgen Macarena, Facultad de Medicina, Sevilla, Spain.
Guerrero
J M
JM
Lucas
M
M
D000262:Adenylyl Cyclases / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D004357:Drug Synergism; D006801:Humans; D008163:Luminescent Measurements; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism; D011493:Protein Kinase C / Q000502:physiology; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
D003208:Concanavalin A; D013481:Superoxides; D005576:Colforsin; D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP; D011493:Protein Kinase C; D000262:Adenylyl Cyclases; D013755:Tetradecanoylphorbol Acetate