ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
The potent tumor promoter tetradecanoyl phorbol acetate (TPA) induces early changes in ion movements analogous to those induced by prostaglandins E1 and F2α. Among the earliest changes induced by TPA is a significant increase in 32Pi incorporation within 15 minutes incubation of TPA (10-8-10-6 M) with post-confluent Swiss 3T3 mouse embryonic fibroblasts. Similarly, the active phorbol ester homolog 4-;β-;OH phorbol didecanoate but not the inactive stereoisomeric 4-β-OH phorbol didecanoate stimulated 32Pi incorporation. Also, TPA at the above concentrations stimulated 86Rb+ influx shortly after administration. Both fluxes were ouabain-sensitive in accord with the idea that an early effect of TPA is to alter (Na+ + K+)-ATPase activity. Further, prostaglandin E1 (10-7-10-6 M) and prostaglandin F2α (3 × 10-9-10-7 M) caused a similar stimulation of 86Rb+ and 32Pi uptake. The finding that water-soluble prostaglandin F2α also exhibited stimulatory effects indicated that those hormone-induced responses are not mediated by solvent interactions. The similar responses of phorbol esters and prostaglandin derivatives suggests that phorbol esters and prostaglandin derivatives may act at common membrane sitesThe finding that stimulatory effects were observed at discrete times in the logarithmic phase of growth suggests that the activation of membrane receptors may be cell-cycle dependent.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1040950306
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