Brain tissue potassium in normal and potassium depleted rats

The potassium concentration of muscle, brainstem and diencephalon were studied in normal and potassium-depleted rats. With 13% depletion of muscle potassium there was a 2.1% and 2.8% decrease in brainstem and diencephalon tissue potassium respectively. With 34% depletion of muscle potassium there was a 1.9% and 4.0% decrease in brainstem and diencephalon tissue potassium. These small decreases in regional brain tissue potassium could be related to observed functional alterations in the potassium depleted rat, i.e., altered cerebrospinal fluid bicarbonate regulation and altered control of the pattern of breathing and of body temperature regulation.