Anaerobic exercis affects NA+-H+-Exchanger activity in human lymphocytes

Mooren FC, Lechtermann A, Mühlenkamp K, Fromme A, Thorwesten L, Völker K

Abstract

The Na+- H+- exchanger is an essential part of cellular pH-regulation (pHi), volume control and cell differentiation. Moreover, its implication in the pathogenesis of hypertension has been mentioned. Therefore the objective of the present study was to investigate its activity after acute and chronic acid loading during exercise. In part I of the study 16 healthy volunteers performed an incremental treadmill exercise test until exhaustion. Blood was taken before and 1 hour after the test. In part II of the study 8 healthy volunteers performed ananaerobic training for 5 days consisting of 4 x 400m runs per day (2 in the morning; 2 in the afternoon). Bloodwas taken at day 1 before training and the day after the last training unit. Lymphocytes were isolated using density-gradient centrifugation. pHi was measured using the pH sensitive fluorescent indicator BCECF. Cells were acidified using propionic acid and the pHi recovery was investigated. Mean resting pHi of lymphocytes isolated before exercise was 7,26+0,01. Exercise did not affect resting pHi. In contrast, the recovery of pHi after acidification of lymphocytes by propionic acid was significantly enhancedafter both the treadmill test and the 5 day anaerobic training. These results indicate that acid-loading during anaerobic exercise increases the acid-extruding capacity in human lymphocytes, most likely by changing the Na+-H+-exchanger activity. Moreover, a single bout of exercise is sufficient to induce an exchanger adaptation and after anaerobic training this adaptation lasts for at least 24hours after the last training unit