Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-5-16
pubmed:abstractText
Rhodamine 123 is a lipophilic cationic fluorescent dye that localizes in mitochondria. We found that 17 beta-estradiol changes the ability of GH4C1 cells, clonal rat pituitary tumor cells, to retain rhodamine 123. Cells incubated with 10 micrograms/ml rhodamine 123 for 30 min at 37 C took up about equal amounts of rhodamine 123, as determined by fluorescence microscopy, regardless of whether they had been treated with estradiol. After three 5-min washes at 37 C, cells treated with 1 nM estradiol for 7 days before incubation with rhodamine 123 had lost more fluorescence than untreated cells. We further characterized the effect by flow cytometry. The difference in fluorescence between control and treated cells ranged from 50- to 500-fold. The effect of estradiol was maximal at 10(-10) M and took a week to develop fully. The effect is specific for estradiol, because estradiol and diethylstilbestrol reduced retention of rhodamine 123 fluorescence at 10(-10) M, but the same concentrations of dihydrotestosterone, progesterone, dexamethasone, and cholesterol did not. To test if the effect on rhodamine 123 fluorescence was caused by activation of the multidrug resistance transport system, we examined the effect of estradiol on the retention of daunomycin, a known substrate of the transport system. Estradiol treatment caused a 3-fold decrease in daunomycin fluorescence. We isolated clones resistant to estradiol-induced loss of rhodamine 123 fluorescence by flow cytometry and found that two clones still showed an estradiol-induced decrease in daunomycin fluorescence equivalent to that of the parent line.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
4
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
140-5
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Estradiol decreases retention of rhodamine 123 fluorescence in GH4C1 pituitary tumor cells.
pubmed:affiliation
Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.