Abstract：In order to better understand the proliferation and differentiation of intramuscular preadipocyte and to clarify factors influence its proliferation and differentiation, cells from adipose tissues within muscles between the sixth and the seventh rib were cultured by means of using collagenaseⅠdigestive method. The results were as follows: the separated cells were highly homogeneous, highly proliferative and with a high differentiation rate. Their dynamic morphological changes, growth curve, oil O staining, and reaction to insulin and dexamethasone all verified their preadipocyte identity. Under controlled conditions, the intramuscular preadipocytes replayed their proliferation and differentiation process in vitro, especially, their euploid status was proved by the analysis of chromosome. In conclusion, the study confirmed there are functionally active preadipocytes in adult cattle’s adipose tissues within muscles, which gives a theoretical basis for improving meat quality by further studying the deposition of intramuscular adipose tissues.
