title: G2 cell cycle arrest induced by glycopeptides isolated from the bovine cerebral cortex.
abstract: The ability of glycopeptides, isolated from bovine cerebral cortex, to alter cell division was studied by cell-cycle analyses. The results showed that glycopeptides arrested baby hamster kidney (BHK)-21 cells and Chinese hamster ovary (CHO) cells in the G2 phase of the cell cycle. Upon removal of the growth inhibition from arrested BHK-21 cells, the mitotic index in colchicine-treated cultures increased from 5 to 40% within 6 h and the increase in mitotic activity was accompanied by a complete doubling of all arrested cells within this 6-h time period. Determination of DNA content in growth-arrested BHK-21 cells showed that growth-arrested cells contained about twice the DNA of control cell cultures. Although CHO cells treated in a like manner with growth inhibitor could not be arrested for the same length of time as BHK-21 cells (18 h vs. 72 h before initiation of escape) and to the same degree (60% of the cell population vs. 99% of BHK-21 cells), the escape kinetics of CHO cells did indicate a G2 arrest. Approximately 3.5 h after escape began, CHO cell numbers in treated cultures attained the cell numbers found in control cultures. This rapid growth phase occurring in less than 4 h indicated that the growth inhibitor induced a G2 arrest-point in CHO cells that was not lethal since the entire arrested cell population divided.
mesh_terms: D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism*; D006224:Cricetinae; D004247:DNA / Q000032:analysis; D005260:Female; D006020:Glycopeptides / Q000302:isolation & purification / Q000494:pharmacology*; D006131:Growth Inhibitors / Q000302:isolation & purification; D007399:Interphase / Q000187:drug effects*; D007668:Kidney; D010053:Ovary
chemical_list: D006020:Glycopeptides; D006131:Growth Inhibitors; D004247:DNA