Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1976-8-2
pubmed:abstractText
The passive permeability of isolated chromaffin vesicles to H+ and the internal pH of the vesicles under various conditions were measured. Potentiometric measurements of K+ and H+ fluxes in the presence of selected ionophores and uncouplers indicated that the membrane is highly impermeable to both protons and potassium. deltapH across the chromaffin granule membrane was measured by [14C]methylamine distribution. At pH 6.85, The deltapH WAS 1.16 WITH THE INTRAVESICULAR SPACE BEING FOUND ACIDIC. Varying the external pH produced an equivalent change in the deltapH, WITH EXTRAPOLATION TO ZERO DEltapH yielding a value of pH 5.5, WHICH IS TAKEN AS AN INDICATION OF THE PH of the intravesicular space. The pH gradient could be enhanced or collapsed by the addition of ionophores and uncouplers under varying ionic conditions. deltapH was constant for granules suspended in various ionic media, suggesting that the deltapH did not arise secondarily due to the establishment of a Donnan equilibrium. The significance of the proton impermeability and deltapH is discussed in terms of regulation of the uptake and storage of catecholamines in bovine chromaffin granules.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
251
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2189-91
pubmed:dateRevised
2009-10-27
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Internal pH of isolated chromaffin vesicles.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.