The uptake and transport behavior of berberine in Coptidis Rhizoma extract through rat primary cultured cortical neurons.

The objective of this study was to investigate whether berberine in Coptidis Rhizoma extract could be transported in primary cultured cerebral neurons and to study the uptake and transport behavior of berberine through the neurons. The present results showed that the uptake of berberine by the neurons increased linearly with increasing concentration of berberine in Coptidis Rhizoma extract over the range of 0.3822-38.22 microg/mL. Berberine could be transported into the neurons in a concentration-dependent and time-dependent manner when the neurons were fed with the incubation medium containing Coptidis Rhizoma extract. There was a positive correlation between the concentration of berberine in the medium and in the cell, which means that uptake of berberine increased in the cell along with higher dose of the extract. But there was a negative correlation tendency between the concentration of berberine in the medium and the penetration ratio. It is suggested that berberine in Coptidis Rhizoma extract was transported into the neurons at a variable rate.