Involvement of purine nucleotide synthetic pathways in gonadotropin‐induced meiotic maturation in mouse cumulus cell‐enclosed oocytes
SM Downs - Molecular Reproduction and Development …, 1997 - Wiley Online Library
… oocyte maturation in meioti- successive periods of meiotic arrest and resumption durcally
arrested cumulus cell-enclosed oocytes. Oo-cytes ing the ontogeny of the oocyte. The …
arrested cumulus cell-enclosed oocytes. Oo-cytes ing the ontogeny of the oocyte. The …
Purine control of mouse oocyte maturation: evidence that nonmetabolized hypoxanthine maintains meiotic arrest
SM Downs - Molecular Reproduction and Development, 1993 - Wiley Online Library
… In B, cumulus cell-enclosed oocytes were maintained in meiotic arrest 17-18 h in … Cumulus
cell-enclosed oocytes were maintained in meiotic arrest by varying concentrations of a …
cell-enclosed oocytes were maintained in meiotic arrest by varying concentrations of a …
Maintenance of murine oocyte meiotic arrest: uptake and metabolism of hypoxanthine and adenosine by cumulus cell-enclosed and denuded oocytes
SM Downs, DL Coleman, JJ Eppig - Developmental biology, 1986 - Elsevier
… follicle cells or the oocyte to other purine derivatives which, … , cumulus cell-enclosed and
denuded oocytes were isolated … , cumulus cell-enclosed oocytes were isolated and washed in …
denuded oocytes were isolated … , cumulus cell-enclosed oocytes were isolated and washed in …
Metabolite supply in oocytes of Nereis virens: role of nucleosides
U Hoeger, N Rebscher, G Geier - Reproductive Strategies and …, 1999 - Springer
… oocyte growth. This overview focusses on the role of exogenous purine nucleosides for the
growing oocytes. … male and female germ cells are not enclosed in a nutritive (follicular) tissue …
growing oocytes. … male and female germ cells are not enclosed in a nutritive (follicular) tissue …
Maintenance of meiotic arrest in mouse oocytes by purines: modulation of cAMP levels and cAMP phosphodiesterase activity
SM Downs, SAJ Daniel, EA Bornslaeger… - Gamete …, 1989 - Wiley Online Library
… Hypoxanthine maintained 80% of cumulus cell-enclosed oocytes in … oocyte-cumulus cell
complexes, yet this purine nucleoside increased the inhibitory effects of hypoxanthine on oocyte …
complexes, yet this purine nucleoside increased the inhibitory effects of hypoxanthine on oocyte …
Induction of mouse oocyte maturation in vivo by perturbants of purine metabolism
SM Downs, JJ Eppig - Biology of reproduction, 1987 - academic.oup.com
… metabolic pathways in vivo might induce the resumption of oocyte maturation. To test this …
enzymes in the purine metabolic pathways. Cumulus cell-enclosed oocytes were isolated from …
enzymes in the purine metabolic pathways. Cumulus cell-enclosed oocytes were isolated from …
Meiotic induction in cumulus cell-enclosed mouse oocytes: involvement of the pentose phosphate pathway
SM Downs, PG Humpherson… - Biology of …, 1998 - academic.oup.com
… Fully grown mammalian oocytes spontaneously resume meiotic maturation when removed
… -enclosed oocytes can be blocked in prophase I if the medium is supplemented with purines …
… -enclosed oocytes can be blocked in prophase I if the medium is supplemented with purines …
Uptake and metabolism of adenosine mediate a meiosis‐arresting action on mouse oocytes
SM Downs - Molecular Reproduction and Development …, 1999 - Wiley Online Library
… To measure uptake by cumulus cell– enclosed oocytes (CEOs), … end of culture and the
oocytes were washed and processed for … Oocytes were cultured for 3 hr and purines were added …
oocytes were washed and processed for … Oocytes were cultured for 3 hr and purines were added …
Culture conditions affect meiotic regulation in cumulus cell‐enclosed mouse oocytes
SM Downs, AM Mastropolo - Molecular Reproduction and …, 1997 - Wiley Online Library
… on oocyte maturation and de novo purine synthesis. Cumulus cell-enclosed oocytes were
… We next determined whether FSH-stimulated de novo purine synthesis is compromised in L-…
… We next determined whether FSH-stimulated de novo purine synthesis is compromised in L-…
High performance liquid chromatography analysis of hypoxanthine metabolism in mouse oocyte-cumulus cell complexes: Effects of purine metabolic perturbants
SM Downs - Biology of reproduction, 1994 - academic.oup.com
… The initial 1-h incubation assured that the drugs used had ample time to act before introduction
of the radiolabeled purine. For oocyte maturation, cumulus cell-enclosed oocytes were …
of the radiolabeled purine. For oocyte maturation, cumulus cell-enclosed oocytes were …