Abstract
Purpose: :
Baicalein, a major flavonoid derived from the medicinal herb Scutellariae radix, is multifunctional: it is anti-inflammatory, anti-tumor and it can modulate ion transport. This study aimed at investigating the effects of baicalein on the transepithelial electrical parameters of isolated porcine iris-ciliary body.
Methods: :
Fresh native porcine CBE preparation was mounted in a modified Ussing chamber. The effect of baicalein on the potential difference was determined. The effects on the CBE preparation of a number of known chloride transport inhibitors were also studied with baicalein.
Results: :
The application of baicalein on aqueous side induced a concentration-dependent reduction in PD, while there was no significant effect when added on blood side. 100uM baicalein on aqueous side decreased 51% of the baseline potential difference (n=10). After bilateral chloride substitution, baicalein significantly reduced the PD by 11% (n=10). Bilateral addition of bumetanide (100uM , a NKCC inhibitor) before baicalein treatment, reduced the depolarization of baicalein by 50% (n=7). Addition of NFA (1mM, a chloride channel blocker) on aqueous side completely abolished the effect of baicalein (n=5).
Conclusions: :
These data showed that baicalein can evoke a depolarization of the transepithelial potential difference of porcine CBE, and this effect is mainly due to the modulation of chloride transport across the porcine CBE.
Keywords: ciliary body • electrophysiology: non-clinical