Structure-activity relationship of Baifuzi-cerebrosides on BKCa channel activation.

Our previous study reported that a mixture of cerebrosides from traditional Chinese medicine Baifuzi could activate BKCa channel. It is curious to know the effect of each single cerebroside on the channel. Here we isolated 5 pure cerebrosides from the mixture and determined their chemical structures. The most potent one increased the single channel open probability 6 folds with EC50 value of 1.0 μM. The structure-activity relationship revealed that acyl chain length of cerebrosides has potent effect, while configuration of double bond at C8-C9 on their long chain base has weak effect on the channel activity. Thus, this research provides a guide for design and synthesis of a lead cerebroside with more potent effect on the BKCa channel.