Abstract
The present study was conducted to determine whether zinc ions are involved in the modulation of substance P release from cultured rat dorsal root ganglion (DRG) neurons. We show here that that lower concentrations (10−8 – 10−7 M) of zinc ions may evoke an extracellular Ca2+ influx through L-, N-, and T-type voltage-dependent Ca2+ channels, thereby increasing the substance P release from cultured DRG neurons, but higher concentrations (10−6 – 10−4 M) of zinc ions attenuate or even completely mask these responses. Zinc ions therefore seem to be an important modulator of substance P release from primary afferent neurons.
