Sato Keisuke, Yoshida Mitsutoshi, Miyoshi Kazuchika
Laboratory of Animal Reproduction, Faculty of Agriculture, Kagoshima University, Kagoshima, Japan.
Mol Reprod Dev. 2005 Nov;72(3):396-403. doi: 10.1002/mrd.20352.
The present study was carried out to examine the development of pig oocytes after exposing to ultrasound under various conditions. When oocytes were exposed to ultrasound in the sorbitol medium, the blastocyst formation rate was significantly (P < 0.01) higher than that of oocytes exposed in HEPES-TLP-PVA. Optison, an echo-contrast microbubble, prevented the development into blastocysts of oocytes exposed to ultrasound in the sorbitol medium (P < 0.01). The mean number of cells in the blastocysts developed from oocytes exposed to ultrasound with 10% duty cycle was significantly (P < 0.05) higher than that obtained by using ultrasound with 50% duty cycle. The blastocyst formation rate of oocytes exposed to ultrasound for 30 sec was significantly (P < 0.05) higher than that exposed for 10 sec. There were no significant differences in the rates of oocytes developed to the blastocyst stage and the mean numbers of cells in the blastocysts among different intensities of ultrasound. The pronuclear formation and second polar body extrusion rates of oocytes exposed to ultrasound did not differ from eclectically activated oocytes. Although there was no significant difference in the blastocyst formation rates between different activation methods, the mean number of cells in the blastocysts developed from oocytes activated by exposing to ultrasound was significantly (P < 0.05) higher than that obtained by applying electric pulses. The results of the present study showed that ultrasound stimulation can induce the nuclear activation and parthenogenetic development of pig oocytes matured in vitro.
本研究旨在检测猪卵母细胞在不同条件下经超声处理后的发育情况。当卵母细胞在山梨醇培养基中接受超声处理时，其囊胚形成率显著高于在HEPES-TLP-PVA中接受超声处理的卵母细胞（P<0.01）。超声造影微泡Optison可抑制山梨醇培养基中经超声处理的卵母细胞发育为囊胚（P<0.01）。 duty cycle为10%时经超声处理的卵母细胞发育而成的囊胚中的平均细胞数显著高于duty cycle为50%时的情况（P<0.05）。经超声处理30秒的卵母细胞的囊胚形成率显著高于处理10秒的情况（P<0.05）。不同强度超声处理的卵母细胞发育至囊胚阶段的比率以及囊胚中的平均细胞数无显著差异。经超声处理的卵母细胞的原核形成率和第二极体排出率与电激活卵母细胞无差异。尽管不同激活方法的囊胚形成率无显著差异，但经超声激活的卵母细胞发育而成的囊胚中的平均细胞数显著高于电脉冲激活的情况（P<0.05）。本研究结果表明，超声刺激可诱导体外成熟的猪卵母细胞核激活和孤雌发育。
