Tubulin pools in human erythrocytes: altered distribution in hypertensive patients affects Na+, K+-ATPase activity

AMAIDEN MR ; SANTANDER VS; MONESTEROLO NE; CAMPETELLI AN; RIVELLI JF; PREVITALI G; ARCE CA; CASALE CH

CELLULAR AND MOLECULAR LIFE SCIENCES

BIRKHAUSER VERLAG AG

Año: 2011 vol. 68 p. 1755 - 1768

1420-682X

The presence of tubulin in human erythrocyteswas demonstrated using five different antibodies. Tubulinwas distributed among three operationally distinguishablepools: membrane, sedimentable structure and solublefraction. It is known that in erythrocytes from hypertensivesubjects (HS), the Na?, K?-ATPase (NKA) activity ispartially inhibited as compared with erythrocytes fromnormal subjects (NS). In erythrocytes from HS the membranetubulin pool is increased by *150%. NKA wasfound to be forming a complex with acetylated tubulin thatresults in inhibition of enzymes. This complex was alsoincreased in erythrocytes from HS. Treatment of erythrocytesfrom HS with nocodazol caused a decrease ofacetylated tubulin in the membrane and stimulation ofNKA activity, whereas taxol treatment on erythrocytesfrom NS had the opposite effect. These results suggest that,in erythrocytes from HS, tubulin was translocated to themembrane, where it associated with NKA with the consequentenzyme inhibition.