Modulation of the Na(+)-H(+) antiport activity by adrenaline on erythrocytes from normal and obese individuals.
The effect of adrenaline on normal and obese human Na(+)-H(+) antiport (NHE 1) erythrocyte activity has been studied. Adrenaline increased both intracellular pH (pHi) and Na(+) influx in erythrocyte suspensions. This effect of adrenaline was inhibited by amiloride or EIPA, indicating that adrenaline stimulated NHE 1. Phorbol myristicate ester (PMA), a protein kinase C (PKC) stimulator, increased the activity of NHE 1 whereas calphostin C, a PKC inhibitor, partially inhibited NHE 1 activation induced by adrenaline. The effect of adrenaline to NHE 1 was counteracted by prazocin and by propranolol as well indicating the involvement of both alpha and beta 2 adrenergic receptors. The effect of adrenaline on erythrocyte NHE 1 activity was significantly more profound in obese compared to normal subjects. These data indicate that adrenaline induces an increase of pHi and Na(+) uptake of human erythrocytes through stimulation of NHE 1 activity. The significantly more profound stimulation of NHE 1 activity by adrenaline in obese as compared to normal subjects is discussed.
Bourikas
Dimitris
D
Zoology Department, Laboratory of Animal Physiology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
Kaloyianni
Martha
M
Bougoulia
Maria
M
Zolota
Zacharoula
Z
Koliakos
George
G
D000584:Amiloride / Q000494:pharmacology; D015992:Body Mass Index; D004837:Epinephrine / Q000494:pharmacology*; D004912:Erythrocytes / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D009765:Obesity / Q000378:metabolism*; D010703:Phorbol Esters / Q000494:pharmacology; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism*; D019311:Staurosporine / Q000494:pharmacology; D013997:Time Factors
D010703:Phorbol Esters; D017923:Sodium-Hydrogen Exchangers; D000584:Amiloride; D019311:Staurosporine; D004837:Epinephrine