Localization of the ATP-sensitive potassium channel subunit (Kir6.1/uK(ATP)-1) in rat brain

The Kir6.1/uK(ATP)-1, subunit of ATP-sensitive K+ channels (K-ATP), was loc alized in adult rat brain by in situ hybridization and immunohistochemistry . The mRNA of this subunit was ubiquitously expressed in various neurons an d nuclei of the adult rat brain. Interestingly, Kir6.1/uK(ATP)-1 mRNA was a lso expressed in glial cells. Kir6.1/uK(ATP)-1 protein staining gave a disp ersed array of fine dots throughout all neurons and glial cells examined. U nder electron microscope, the immunoreactive products were specifically res tricted to the mitochondria. The present study indicates that this K-ATP su bunit is localized in the mitochondria and may play a fundamental role in v ital brain function. (C) 1999 Elsevier Science B.V. All rights reserved.