Prostate cancer cells stimulated by calcium-mediated activation of protein kinase C undergo a refractory period before re-releasing calcium-bearing microvesicles
MVs are released in response to several stress agents, in an attempt to prevent continued cellular damage. After an initial stimulus of prostate cancer cells with sublytic C5b-9 and activation of MV release through PKC, cells take at least 20 min to fully recover their ability to microvesiculate. This release of MVs through activation of sublytic C5b-9 was inhibited by the PKC inhibitor bisindoylmaleimide I but not the Rho kinase inhibitor, Y27632. After stimulus there is a rise of 79 nMs-1 over 11 s, reaching a peak [Ca2+]i of 920 nM. The concentration of cytosolic calcium then falls steadily at 2.4 nMs-1 over 109 s reaching baseline levels (50-100 nM) within 10-15 min. In PC3 cells the rate of release of MVs from stimulated cells also reaches a minimum within 10-15 min. Using fura-2 AM-loaded cells, upon stimulation, cells were found to release MVs with a concentration of intravesicular calcium estimated at ∼430 nM.
Item Type | Article |
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Uncontrolled Keywords | Intravesicular calcium; Microvesicles; Refractory period; Sublytic C5b-9 |
Subjects |
Biochemistry, Genetics and Molecular Biology(all) > Biophysics Biochemistry, Genetics and Molecular Biology(all) > Biochemistry Biochemistry, Genetics and Molecular Biology(all) > Molecular Biology Biochemistry, Genetics and Molecular Biology(all) > Cell Biology |
Date Deposited | 14 Nov 2024 10:34 |
Last Modified | 14 Nov 2024 10:34 |