Fibroblast Na+-Li+ countertransport rate is elevated in essential hypertension.
J Hypertens
; 19(7): 1263-9, 2001 Jul.
Article
in En
| MEDLINE
| ID: mdl-11446716
ABSTRACT
OBJECTIVES:
Elevated erythrocyte Na+- Li+ countertransport (SLC) rates are commonly found in essential hypertension. We have recently shown that human skin fibroblasts functionally express a phloretin-sensitive Na+-H+ exchange (NHE) which may also be similar to erythrocyte SLC because of amiloride-insensitivity. DESIGN ANDMETHODS:
We investigated whether elevations in fibroblast SLC parallel the known elevations in erythrocyte SLC and in cell NHE that characterize essential hypertension.RESULTS:
Higher fibroblast SLC rates were found among hypertensive patients (n = 23, median 48.8 nmol Li+/ mg(protein) per min) than in 19 normotensive individuals of similar age and sex (median 14.8 nmol Li+/mg(protein) per min, P= 0.0002). As expected, erythrocyte SLC was elevated in patients with hypertension (median 411 versus 329 micromol/l(cell) per h, P= 0.0273), but was not quantitatively related to fibroblast SLC. Finally, fibroblast NHE exchange activity was higher in essential hypertension (median Vmax 14.2 versus 7.6 mmol H+/l(cell) per min, P= 0.002), but was unrelated to fibroblast SLC.CONCLUSIONS:
These findings extend to human skin fibroblasts the notion of abnormal Li+ transport in essential hypertension, and appear to be in accordance with the hypothesis that fibroblast SLC may be independent of NHE. However, molecular studies will be required to understand whether distinct exchangers and/or regulation mechanisms underlie these dysregulations.
Search on Google
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Skin
/
Antiporters
/
Fibroblasts
/
Hypertension
Limits:
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
J Hypertens
Year:
2001
Document type:
Article
Affiliation country:
Italia