Effects Of Anaesthesia And Genital Tract Stimulation-Induced On Reproduction And Endocrine In Kunming Mice

In this study, the effect of Ketamine-HCL in varying dosages on ovulation in Kun Ming mice was determined by experiment. Additional experiments established the effect of anesthesia HI with Ketamine-HCL (150mg/kg) on oocytes, pre-implantation of embryos, and the reproductive outcome in mice. In addition, the effects of genital tract stimulation-induced anesthesia on serum oxytocin (OT) levels were determined by R&D systems oxytocin immunoassay.Experiments were carried out in four parts. The results were the following:Part I: Injection of variety dose of Ketamine-HCL(50mg/kg,100mg/kg and 150mg/kg) revealed a high significant decrease in the numbers of superovulated oocytes when compared to control groups (P less than 0.01). The dosage of 100-150mg/kgweight Ketamine-HCL was the most appropriate forAnesthesia III in this study.Part II: There was a significant decrease in the number of oocytes of superovulated mice under anesthesia after injection of hCG when compared to control groups (P less than 0.01). Both the abnormal rates (30.5% vs.12.1%, P less than 0.01) and parthenogeneic activation rates by ethanol (58.3% vs. 23.4%, P less than 0.01) were also significantly increased in the group under anesthesia. However, the extrusion rates of polar bodies after 0 hours and 8 hours were not significantly affected by anesthesia.Part III: In this experiment, ovulation occurred at 2:30-4:00 for mice induced by PMSG-hCG; Under natural conditions, ovulation occurred at 22:30-0:30. Both ovulation induced by PMSG-hCG and ovulation under natural conditions were significantly reduced or compromised by pre-ovulatory anesthesia. However, the oocyte numbers and blastocyst numbers for middle-ovulatory and post-ovulatory anesthesia group showed no significant differences compared with control group. These results would indicate that anesthesia could cause some abnormal oocytes and blastocysts.Under natural conditions, five of the 12 mice (41.67%) became pregnant during in pre-ovulatory anesthesia when compared with a control group of 12 of 12 mice (100%). In addition, the birth weight for post-ovulatory anesthesia group also showed a significant decline. There were no apparent differences in conception rate of ovulatory and post-ovulatory anesthesia groups when compared with control groups. However, pre-ovulatory anesthesia caused considerable changes in the number of births although showed no significant differences when anesthesia was carried out at ovulation andpost-ovulation as compared to controls. These results would suggest that post-ovulatory anesthesia can cause a high mortality rate. Furthermore, injection of Ketamine-HCL at ovulation and post-ovulation also caused some early delivery in some females.Part IV: In this experiment release of oxytocin (OT) during anesthesia, induced by genital tractstimulation, and induced by genital tract stimulation associated with anesthesia were measured duringestrus. Data indicated that significant change in oxytocin (OT) levels did not occur in each group. Theresult, which was different from another study, may be from the SEM (SA=127.677,SG=157.59, SA-G=229.1,Sco,tois:=l 78.25). On average, induced genital tract stimulation could provoke release of OT. However, OT concentration was declined by injection dosage of Anesthesia 111(150mg/kg). Therefore, induced genital tract stimulation after injection of Ketamine-HCL can reduce the inhibiting effect of OT release.In conclusion, ovulation in mice is inhibited by pre-ovulatory Ketamine-HCL. In addition, deaths of some neonates occurred during post-ovulatory anesthesia. It is noted that anesthesia of mice when ovulation occurs, results in a relatively high numbers of oocytes and blastocysts, increased incidence of pregnancy, and increased survival rates of neonates.