[Experimental study of the effects of time-phased cryopreservation and resuscitation on biological characters of osteoblasts].

This is an in vitro study to explore the effects of cryopreservation and resuscitation on the biological characteristics of osteoblasts at different times. Osteoblasts taken from the crania of newly born SD rats were cultured. Comparative studies were made on the cells' proliferation, the activity of alkaline phosphatase (ALP), and the number of live cells among fresh cultured osteoblasts and cells after the inception of cryopreservation and resuscitation at time-periods of one, three, six months respectively. The results showed that there were no significant differences among four groups in cell proliferation and in activity of ALP (P > 0.05). Yet, after cryopreservation and resuscitation, there were significant differences between the six-month group and the other three groups (P < 0.05). The results also showed, after cryopreservation and resuscitation, there were no significant differences between the control group and the one-month and three-month groups, respectively (P > 0.05). These findings indicated that the live cells might decrease in number after the osteoblasts were cryopreserved for too long a period, but after cryopreservation and resuscitation, the cells still retained the original biological characteristics of osteoblasts.