Abstract
Intrinsic buffering power (beta i) has been measured in vascular strips and single cells from rat mesenteric artery. Intracellular pH (pHi) regulation was inhibited to prevent overestimation of beta i due to acid extrusion or entry via regulatory processes. At resting values of pHi (7.0-7.2), a mean value of 41 +/- 4 mM/pH unit for beta i was found. beta i increased approximately fivefold from 30 to 150 mM/pH unit over the pHi range 7.5-6.5. The mean data relating beta i to pHi could be described by relating beta i to buffer concentrations and pKa. This gave a value of 310 mM for buffer concentration and a pKa of 6.0. As changes in pHi are known to have marked effects on vascular tone then the increase in beta i as pHi falls may be considered as a means of attenuating pHi decreases, before pH regulation restores pHi to resting levels.
Original language | English |
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Pages (from-to) | 325-31 |
Number of pages | 7 |
Journal | Pflugers Archiv European Journal of Physiology |
Volume | 429 |
Issue number | 3 |
DOIs | |
Publication status | Published - 31 Jan 1995 |
Keywords
- Animals
- Benzopyrans
- Buffers
- Butyrates/pharmacology
- Butyric Acid
- Fluorescent Dyes
- Hydrogen-Ion Concentration
- In Vitro Techniques
- Male
- Mesenteric Arteries/chemistry
- Methylamines/pharmacology
- Muscle, Smooth, Vascular/chemistry
- Rats
- Rats, Wistar