Abstract: Folowing sterilization human scalps were cut into thin strips about 0.3～0.5 cmwide,then the skin was separated at the dermo-subcutaneous fat interface.The intact hair folicles were puled out from the subcutaneous fat using watchmakers' forceps and maintained free-floating in DMEM medium supplemented with insulin,hydrocortisone and 10% new-born calf serum.They showed a significant increase in length over 4 days(P<0.01),the average rate of growth was 0.17mm/d and quickest in the first two days.³H-thymidine autoradiography showed that DNA synthesis mainly occurred in the hair matrix cells and some basal cells of outer root sheath,which indicated that the growth and prolongation of hair follicles were resulted from the division and proliferation of hair matrix cells, and some basal cells of outer root sheath took part in the growth of outer root sheath.After four days of culture the hair folicles began to attach and keratinocytes migrated out from outer root sheath.In the first four days the morphology of hair folicles remained unchanged,then the hair shaft became club shaped,and the dermal papila became a tight ball of cells.

Key words: Hair folicle, Organ,culture