Carba prostacyclin enhances the capsaicin-induced cobalt-loading of rat sensory neurons grown in culture.

Sensory neurons isolated from the dorsal root ganglia of embryonic rats and grown in culture are distributed into two populations based on cross-sectional areas and sensitivity to capsaicin. Of the total neuronal population, about 48% of the neurons are labelled by cobalt in the presence of 1 microM capsaicin. The distribution of the small-sized neurons coincides with that of the capsaicin-cobalt-labelled neurons. When a lower concentration of capsaicin (100 nM) is used, pretreatment of sensory neurons with carba prostacyclin, a stable analog of prostaglandin I2, produces a three-fold enhancement in the number of neurons that are cobalt-labelled by capsaicin compared with that in the absence of carba prostacyclin.