Effect of antihypertensive treatment on intracellular calcium concentration and intracellular pH in essential hypertension.

Abstract

The platelet intracellular calcium concentration ([Ca2+]i) and intracellular pH (pHi) were measured by spectrofluorimetry with the dyes Fura-2 and BCECF, respectively, in 19 patients with essential hypertension (10 males), aged 48 +/- 2 years, before and after 12 weeks of antihypertensive treatment and in 19 normotensive controls (11 males), aged 46 +/- 3 years. [Ca2+]i and pHi were measured in the resting state and after stimulation in vitro with 0.1 U/ml human thrombin. In patients with essential hypertension, both resting [Ca2+]i (61 +/- 4 nmol/l) and thrombin-induced maximal increase in [Ca2]i (291 +/- 26 nmol/l) were significantly (P < 0.01) greater than in the normotensive controls (resting 49 +/- 2 nmol/l and thrombin-induced 199 +/- 21 nmol/l). With respect to pHi, no difference in resting pHi between both groups was found (7.16 +/- 0.01 vs. 7.16 +/- 0.01). However, pHi increment at 300 seconds in response to thrombin was higher in the patients with essential hypertension than in the controls (0.131 +/- 0.02 vs. 0.083 +/- 0.01 pH units, P < 0.05). The increment in pHi was blunted by the amiloride derivative EIPA, indicating that it was mediated by the Na+/H+ exchanger. After antihypertensive therapy in the essential hypertensive patients, basal [Ca2+]i was significantly reduced (52 +/- 2 nmol/l, P < 0.01) and was not statistically different to the value found in the normotensive controls. Resting pHi suffered no significant modification after treatment (7.17 +/- 0.01, P = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: E Poch, A Botey, J Gaya, A Darnell, F Rivera, L Revert
• Journal: Journal of human hypertension (J Hum Hypertens) Vol. 8 Issue 6 Pg. 461-7 (Jun 1994) ISSN: 0950-9240 [Print] England
• PMID: 8089832 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antihypertensive Agents
• Sodium-Hydrogen Exchangers
• Calcium

Topics

• Adult
• Antihypertensive Agents (pharmacology)
• Blood Platelets (drug effects, metabolism)
• Calcium (blood)
• Female
• Humans
• Hydrogen-Ion Concentration (drug effects)
• Hypertension (blood, drug therapy)
• Male
• Middle Aged
• Sodium-Hydrogen Exchangers (blood)
• Spectrometry, Fluorescence