I am routinely using the ROCK inhibitor for iPSC passaging. 1 day after seeding, I normally switch to iPSC media without the ROCKi but once I left it over the weekend with ROCKi and surpassingly observed that the cells did not grow almost at all and maintained the single cell morphology. After that I switched back to the media without and some cells seem to cluster more similar to an iPSC colony but the growth is still pretty slow. I would have thought it would not have such a dramatic change. Does anyone know if long term exposure of ROCKi affect iPSC metabolism and growth rate? Thanks.