Identification of phosphodiesterase 9A as a cyclic guanosine monophosphate-specific phosphodiesterase in germinal vesicle oocytes: a proposed role in the resumption of meiosis.
OBJECTIVE
To identify a cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase (PDE) in nonhuman primate germinal vesicle (GV) oocytes and establish a proposed effect on oocyte maturation through preliminary experiments in mouse GV oocytes.


METHODS
Controlled nonhuman primate and rodent experiments.


METHODS
Academic research institution.


METHODS
Rhesus macaques and B6/129F1 mice.


METHODS
Stimulation of Rhesus macaques with follicle-stimulating hormone (FSH) to collect GV oocytes and cumulus for gene expression analysis, and stimulation of female mice with pregnant mare serum gonadotropin to collect GV oocytes.


METHODS
Expression of PDE transcript in primate GV oocytes and cumulus cells, measurement of fluorescence polarization of phosphodiesterase 3A (PDE3A) activity, and analysis of spontaneous resumption of meiosis in mouse GV oocytes.


RESULTS
Of five PDE transcripts detected in Rhesus GV oocytes, only PDE9A was cGMP-specific. The fluorescence polarization assays indicated cGMP has an inhibitory effect on PDE3A while the phosphodiesterase 9A (PDE9) inhibitor, BAY73-6691, does not. Similarly, BAY73-6691 had little effect on preventing spontaneous maturation in oocytes, but did augment the inhibitory effects of cGMP. Inclusion of 0 μM (control), 10 μM, 100 μM, and 1 mM BAY73-6691 statistically significantly increased the proportion of mouse oocytes maintaining GV arrest in the presence of the cGMP analog 8-Br-cGMP at 100 μM (8.8%, 11.4%, 18.8%, and 28%), 500 μM (21.1%, 38.1%, 74.5%, and 66.5%), and 1 mM (57.8%, 74.5%, 93.9%, and 94.0%), respectively.


CONCLUSIONS
Phosphodiesterase 9A (PDE9A) is a cGMP-specific hydrolyzing enzyme present in primate oocytes, and PDE9 antagonists augment the inhibitory effect of cGMP during spontaneous in vitro maturation of GV mouse oocytes.
Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Beaverton, Oregon 97239, USA.
Carol B
CB
Hanna
Shan
S
Yao
Xuemei
X
Wu
Jeffrey T
JT
Jensen
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors / Q000502:physiology*; D000818:Animals; D002478:Cells, Cultured; D018920:Coculture Techniques; D006152:Cyclic GMP / Q000502:physiology*; D005260:Female; D008253:Macaca mulatta; D008540:Meiosis / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D009865:Oocytes / Q000187:drug effects / Q000201:enzymology*; D011720:Pyrazoles / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology
C507056:BAY 73-6691; D011720:Pyrazoles; D011743:Pyrimidines; D015105:3',5'-Cyclic-AMP Phosphodiesterases; C507055:Pde9a protein, mouse; D006152:Cyclic GMP