en Cellular and molecular Neuroscience Cellular and molecular Neuroscience Original Original <div style="text-align: justify;"><strong>Introduction</strong>: Several types of ion channels found in the plasma membrane have also been identified in the membranes of intracellular organelles. These ion channels, including potassium channels, play a crucial role in regulating intracellular ion homeostasis. An ATP-sensitive potassium (KATP) channel with various functional roles has been identified in the endo/sarcoplasmic reticulum membranes of both excitable and non-excitable cells. Our previous studies investigated the electropharmacological and molecular properties of KATP and BKCa+2 channels in the rough endoplasmic reticulum (RER) of rat hepatocytes.&nbsp;<br> <strong>Methods</strong>: In this study, for the first time, we described the electropharmacological and molecular properties of the RER KATP channel in rat brain cells using an incorporated single-channel in a planar lipid bilayer and Western blotting.&nbsp;<br> <strong>Results</strong>: The results of the study revealed the presence of a KATP channel with a conductance of 306 pS, and the open probability was found to be voltage-independent at holding potentials ranging from +40 to -60 in an asymmetric solution (200/50 mM KCl; cis/trans). Additionally, we observed that adding ATP (2.5 mM) to both positive and negative potentials, and 100 &mu;M glibenclamide to the positive voltages inhibited channel activity. The addition of 100 mM 5-HD and 100 nM charybdotoxin to the cis side did not affect the channel behavior. Furthermore, a Western blot analysis provided evidence of the expression of Kir6.2, Kir6.1, sulfonylurea receptor (SUR)1, and/or SUR2B, but not SUR2A, in the RER of rat brain fractions.<br> <strong>Conclusion</strong>: In this study, we provide strong evidence for the existence of a KATP channel on the RER membrane of rat brain cells, displaying pharmacological properties distinct from those classically described for the plasma membrane and other intracellular organelles.</div> Potassium channels, Rough endoplasmic reticulum (RER), ATP-sensitive potassium (KATP) channel, Bilayer lipid membrane, Single channel recording 1017 1032 http://bcn.iums.ac.ir/browse.php?a_code=A-10-1137-1&slc_lang=en&sid=1 Maryam Nazari Maryam.nazari991@gmail.com 13700319475328460056611 13700319475328460056611 No Department of Physiology, School of Medicine, Arak University of Medical Sciences, Arak, Iran. Afsaneh Eliassi af.eliassi@sbmu.ac.ir 13700319475328460056612 13700319475328460056612 No Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Reza Saghiri Saghiri@pasteur.ac.ir 13700319475328460056613 13700319475328460056613 No Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran. Farnaz Nikbakht farnazinikbakht@yahoo.com 13700319475328460056614 13700319475328460056614 No Department of Physiology, Cellular and Molecular Research Center, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Javad Fahanik-babaei Fahanikbabaei1358@gmail.com 13700319475328460056615 13700319475328460056615 Yes Electrophysiology Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.