Study On The Effect Of Microwave Thawing During The Cryopreservation Embryonic Cerebral Cells By Vitrification

In the present study, pregnant SD rats (17~19 days) were used for the studies on the embryonic cerebral cells (ECC) which were cryopreserved by vitrification. The objective of this study was to test whether the microwave thawing could keep the better biological function than the water bath thawing. The suitable procedure of microwave thawing was selected through tested the thawing rates. And the suitable vitrification solution was selected, hi the last, the structures and functions of ECC after cryopreservation were examined, and the factors affecting the viability of ECC were analyzed. The effects of the microwave thawing and water bath thawing was compared.The selection of the microwave parameter: The 2ml vitrification solution which was cryoperserved by vitrificaion was direct thawed with microwave. The result showed that the time thawing was more long if the power was lower. When the power of microwave was 800W, the thawing time was 165 seconds, and the thawing rate reached 71.27/min. This rate was slower than that of 38 water both thawing, whose thawing time was 100 seconds and thawing rate was 117.6/min. If the samples were pulled into water both and then were thawed with microwave together, the thawing rates were improved. The suitable volume of the water both was 300ml, the suitable temperature was 10. The thawing time by this procedure was 80 seconds, the thawing rate reached 147/min.The selection of the vitrification solution: According to the experiment results of the recovery rates, the survival rates and the vitalities of succinate dehydrogenase (SDH), VS2 solution, consisted of 20.5% (W/V) dimethyl sulfoxide (DMSO), 15.5% (WAV) acetamide, 10% (W/V) 2,3-butylene glycol and 6% (W/V) sucrose in D-Hank's medium, was suitable to embryonic cerebral cells.The changes of the functions of the vitrified embryonic cerebral cells: During the cryopreservation, the recovery rates and the survival rates decreased with the prolongation of cryopreservation. The survival rates after 30 days cryopreservation were steady relatively. The 30-day's survival rates were not different significantly when compared with the 60-day's. At the forepart of the cryopreservation (3-30 days), the contents of H2O2 increased obviously, and the vitalities of SDH and superoxide dismutase(SOD) depressed distinctly. At the evening of the cryopreservation (30-60days), the contents of H2O2, the vitalities of SDH and SOD went to steady status.Comparison of the group of microwave thawing VS the group of water bath thawing: According to the recovery rates, there was no significant differences between the group of microwave thawing and the group of water bath thawing. But the survival rates, the vitalities of SDH and SOD of the cells which thawed by microwave were higher than those of which thawed by water bath. The contents of H2O2 of the cells thawed by microwave were lower than those thawed by water both. It indicated that the damage to the ECC by microwave thawing was lower than that by water both.