Figure 2 illustrates CFTR immunoreactivity in cholangiocytes lining the liver cysts. The CFTR-positive apical membranous staining seen in the control tissue was diminished in the pioglitazone-treated animals. Insufficient CFTR was present in the renal slices for unambiguous detection of changes at the light level although the CFTR channel is clearly present based on functional studies [6, 9–11]. Here, CFTR is linked to Hepatic cysts.