P 2-purinoreceptor evoked changes in intracellular calcium oscillations in single isolated human granulosa-lutein cells

Lee, P. S. N. and Squires, Paul and Buchan, A. M. J. and Yuen, B. H. and Leung, P. C. K. (1996) P 2-purinoreceptor evoked changes in intracellular calcium oscillations in single isolated human granulosa-lutein cells. Endocrinology, 137 (9). pp. 3756-3761. ISSN 0013-7227

Full content URL: http://dx.doi.org/10.1210/endo.137.9.8756543

Full text not available from this repository.

Item Type:Article
Item Status:Live Archive

Abstract

In this study, we have demonstrated that P 2-purinoreceptor agonists evoke oscillatory intracellular calcium (Ca 2+(i)) responses in human granulosa-lutein cells (GLCs). Intracellular calcium was measured using microspectrofluorimetric techniques. ATP at concentrations of 1-100 μM increased Ca 2+(i), whereas neither adenosine nor AMP evoked changes in Ca 2+(i). The nonhydrolysable ATP analogue, ATPγS, also elevated Ca 2+(i) with an efficacy similar to that of ATP, indicating that the changes in Ca 2+ were not due to ATP hydrolysis, but that human GLCs possess functional P 2-purinoreceptors. Uridine triphosphate (UTP) was equipotent to ATP at stimulating Ca 2+(i), and both ATP and UTP were consistently more effective at eliciting a response than ADP, suggesting that human GLCs possess the P(2U) class of purinergic receptors (ATP = UTP >> ADP >> AMP adenosine). We have demonstrated that the purinergic agonist-induced changes in Ca 2+(i) involve both Ca 2+ influx and Ca 2+ mobilization from cytosolic stores. Prolonged ATP treatment in Ca 2+-free buffer (1 mM EGTA) still evokes transient oscillatory changes in Ca 2+(i) in a pertussis toxin-insensitive manner. In Ca 2+-containing conditions, the sustained phase of the response was generally unaffected by verapamil (10 μM), suggesting that influx is not occurring through voltage-dependent Ca 2+- channels. These findings are consistent with the hypothesis that ATP and other P 2-purinergic receptor agonists elicit changes in Ca 2+(i) in human ovarian cells and that these events are initiated by the release of Ca 2+ from cytosolic stores, and sustained by extracellular calcium (Ca 2+(i)) influx. This is the first time that oscillatory patterns of Ca 2+(i) have been reported in human GLCs.

Keywords:calcium channel, purine receptor, uridine triphosphate, adenosine 5' o (3 thiotriphosphate), adenosine 5'-O-(3-thiotriphosphate), adenosine triphosphate, calcium, drug derivative, purine receptor, article, calcium cell level, calcium mobilization, calcium transport, cell culture, cell isolation, granulosa cell, human, human cell, hydrolysis, hypothesis, priority journal, spectrofluorometry, cell separation, corpus luteum, cytology, drug effect, drug potentiation, female, intracellular membrane, metabolism, osmolarity, physiology, Adenosine Triphosphate, Granulosa Cells, Humans, Intracellular Membranes, Osmolar Concentration, Receptors, Purinergic
Subjects:C Biological Sciences > C130 Cell Biology
Divisions:College of Science > School of Life Sciences
ID Code:14470
Deposited On:11 Jul 2014 11:51

Repository Staff Only: item control page