“…Many biological processes, such as enzyme activity, ionic conductance, and activity of membrane transporters, are pH-sensitive (3,4). Thus, the regulation of pH i in neurons is of critical importance; failure to maintain pH i may lead to numerous pathophysiological conditions (5,6). Neurons may become acidified in response to neurotransmitters and chemical compounds (7)(8)(9), and this intracellular acidification has been linked to the activity of the plasma membrane Ca 2ϩ /ATPase (PMCA) (10,11).…”