ATP-induced apoptosis of human granulosa luteal cells cultured in vitro.
OBJECTIVE
To investigate the role of extracellular adenosine triphosphatase (ATP) as an inducer of apoptotic cell death in human granulosa cells and to elucidate its underlying mechanism.


METHODS
Prospective study.


METHODS
Gynecologic clinic and human reproduction research laboratory.


METHODS
Twenty-five patients undergoing IVF or IVF-ET.


METHODS
ATP treatment of granulosa luteal cells subjected to primary culture.


METHODS
Apoptosis was assessed by the annexin V binding assay and the terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling assay. The receptor type that binds ATP, thus mediating ATP-induced apoptosis, was determined by using the calcium imaging and patch-clamp techniques. Mitochondrial depolarization was assessed by staining with the membrane potential-sensitive dye 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolyl carbocyanide iodide (JC-1).


RESULTS
ATP elevated [Ca(2+)](i) by mobilizing intracellularly stored Ca(2+). An ionic membrane current evoked by ATP was mediated by the Ca(2+)-activated K(+) channel. ATP induced a mitochondrial depolarization with a concomitant increase in cellular apoptosis. Treatment with hCG eliminated both ATP-induced mitochondrial depolarization and apoptosis.


CONCLUSIONS
Extracellular ATP recognized by P(2Y) type purinoceptor triggers apoptosis in human granulosa luteal cells, and the downstream apoptotic cascade may act at least in part through mitochondria. The antiapoptotic effect of hCG has possible clinical implications in the treatment of disorders involving granulosa cell degeneration (such as follicular atresia).
Park
Dong-Wook
DW
Department of Molecular Science and Technology, Ajou University, Suwon, South Korea.
Cho
Taesup
T
Kim
Mi Ran
MR
Kim
Young Ah
YA
Min
Churl K
CK
Hwang
Kyung Joo
KJ
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D005260:Female; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism; D008184:Luteal Cells / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000502:physiology; D009994:Osmolar Concentration; D018408:Patch-Clamp Techniques; D011446:Prospective Studies
D006063:Chorionic Gonadotropin; D000255:Adenosine Triphosphate; D002118:Calcium