Control of neurovascular coupling by ATP-sensitive potassium channels

Area of Science:

• Neuroscience
• Physiology
• Molecular Biology

Background:

• Neurovascular coupling (NVC) links brain blood flow to neuronal activity.
• ATP-sensitive potassium (KATP) channels are implicated in various physiological processes.

Purpose of the Study:

• To investigate the role of SUR2- and Kir6.1-dependent KATP channels in controlling NVC in the mouse sensory cortex.
• To determine the effects of modulating KATP channel activity on stimulus-evoked hemodynamic responses.

Main Methods:

• Utilized pharmacological activators (pinacidil) and inhibitors (glibenclamide) of KATP channels.
• Employed SUR2 knockout (KO) mice and mice with gain-of-function (GOF) mutations in Kir6.1.
• Measured cortical hemodynamic responses to mechanical stimuli in conscious mice.

Main Results:

• Pharmacological activation or inhibition of KATP channels markedly disrupted NVC.
• Pinacidil abolished stimulus-evoked responses, while glibenclamide reduced and slowed them.
• SUR2 KO and Kir6.1 GOF mutant mice showed altered NVC, including baseline reductions and increased sensitivity to pinacidil.

Conclusions:

• SUR2/Kir6.1-dependent KATP channels play a critical role in regulating NVC.
• Pharmacological or genetic alterations of these channels significantly impact brain blood flow regulation.
• Findings have implications for understanding monogenic KATP channel diseases and common brain pathologies.