Hypoxanthine and cyclic adenosine 5’-monophosphate maintain meiotic arrest of rhesus monkey oocytes in vitro

Abstract

In the present study, hypoxanthine (HX) and dibutyryl cyclic adenosine monophosphate (dbcAMP) were tested as inhibitors of rhesus monkey oocyte maturation in vitro, because of their similar effect in mice. A significantly larger proportion (72%) of oocytes underwent germinal vesicle breakdown (GVB) in group I (control) after 40 hours in culture, as compared with 21% in treatment group II with HX plus dbcAMP (P less than 0.001). Seventy-five percent of oocytes had GVB by 80 hours after being initially inhibited for 40 hours with HX and dbcAMP; however, only 34% of oocytes had GVB when treated with HX and dbcAMP continuously for 80 hours (P less than 0.005). These results demonstrate that a significant proportion of rhesus monkey oocytes can be maintained in meiotic arrest for 40 hours by treatment with HX and dbcAMP, and that this effect can be overcome by removal of inhibitors from the culture medium.