ABSTRACT
Aim To study modulation of NMDA recep-tors on inward rectifying potassium channels through investigation of retinal horizontal cells. Methods Whole cell recording was conducted on isolated retinal horizontal cells for observation of inward-rectifying po-tassium currents before and after application of NMDA. Modulation of inward-rectifying currents by NMDA re-ceptor was also tested under calcium-free and chelation of intracellular calcium condition. Results Reduction of inward rectifying potassium currents was induced by activation of NMDA receptors. The effect was attenua-ted when calcium was removed. Conclusion Inhibi-tion of inward rectifying potassium channels can be in-duced by activation of NMDA receptors via intracellular calcium signals.