title: Leucocyte intracellular pH and Na+/H+ antiport activity in human hypertension.
abstract: Hypertension is associated with thickening of the wall of resistance vessels, but the cellular or genetic basis of this is unclear. Cell proliferation and intracellular alkalinization via increased Na+/H+ exchange are linked in the response of tissues to growth factors. To define a possible cellular basis for vascular medial thickening in hypertension, we studied leucocyte intracellular pH, buffering power and Na+/H+ antiport activity in 17 hypertensive and 17 age-, sex- and weight-matched normotensive subjects. The cells from hypertensive subjects were significantly more alkaline [median (range): 7.49 (7.26-7.95) versus 7.39 (7.25-7.53); P less than 0.01], and had a lower buffering power [8.95 (3.05-17.98) versus 12.57 (7.44-19.95) mmol/l per pH unit; P less than 0.02] than those from normotensive subjects. Moreover, the activity of the Na+/H+ antiport was higher when cells were acid-loaded to an intracellular pH of 6.7. The presence of a similar increased activity in vascular smooth muscle cells may be associated with increased cellular proliferation resulting in a thickened media or increased vascular smooth muscle contractility.
authors.affiliation: Sheikh Rashid Diabetes Unit, Radcliffe Infirmary, Oxford, UK.
authors.forename: L L
authors.initials: LL
authors.lastname: Ng
authors.forename: C
authors.initials: C
authors.lastname: Dudley
authors.forename: J
authors.initials: J
authors.lastname: Bomford
authors.forename: D
authors.initials: D
authors.lastname: Hawley
mesh_terms: D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000378:metabolism; D001794:Blood Pressure; D001835:Body Weight; D002352:Carrier Proteins / Q000097:blood*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood*; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D017923:Sodium-Hydrogen Exchangers
chemical_list: D002352:Carrier Proteins; D017923:Sodium-Hydrogen Exchangers