Abstract <p>ASIC channels are widely distributed in the mammalian nervoussystem. The properties of these channels are usually studied atroom temperature, despite the high temperature dependence of ASIC1a.In particular, fast desensitization of ASIC1a is accelerated bytemperature rise. Temperature dependence of slow desensitization(tachyphylaxis) is not studied. Our patch clamp experiments on ratASIC1a expressed in chinese hamster ovary (CHO) cells demonstratedthat increasing temperature reduces slow desensitization. We proposethat acceleration of fast desensitization reduces the duration ofthe open state, and thus reduces slow desensitization. Artificialreduction of the open time by short activations reproduces the effectof high temperature on tachyphylaxis. Our finding emphasizes theimportance of physiological temperature conditions for analysisof ASIC1a contribution in physiological processes.</p>