Effects Of Analogues H86A,H74F And H78F Of Osteogenic Growth Peptide On Bone Metabolism In OVX Rats

Objective To investigate the effects of osteogenic growth peptide analogues (H86A,H74F,H78F)on biochemical markers of bone turnover,bone histomorphometry,AW/DW and bone mineral density(BMD)and biomechanical properties in ovariectomized(OVX)rats.Methods Sixty-four female virgin SD rats,three months old,were randomly divided into 8 groups(8 rats in each group): groupl,sham-operated group(S);group2,ovariectomized group(O);group3,low dose H86A treated group;group4,high dose H86A treated group;group 5,low dose H74F treated group;group6,high dose H74F treated group;group 7,low dose H78F treated group;group7,high dose H74F treated group;Ovariectomy was carried out in group 2-8.After being injected subcutaneously with the above agents (Sham-operated and OVX rats being injected with vehicle)once per day for 12 weeks, all rats were sacrificed.Uterus,kidney,liver,lumbar vertebrae(L1-5),bilateral tibiae and femurs were reserved from each rat.Serum ALP and osteocalcin(BGP) was measured by biochemical analysis and radioimmunoassay respectively.The proximal tibiae metaphysis was processed undecalcified for quantitive bone histomorphometry.The BMD was measured over the entire femur and L1-4 by dual energy X-ray absorptiometry(DEXA).Bone strength was measured by three-point bending and compression tests.The data were analyzed by SPSS 10.0.Result 1. Compared with group S,the serum levels of ALP were increased in other groups, especially in the groups of H74FH,H78FH and OVX who were increased significantly(P＜0.01).The serum levels of BGP were higher in group H86AL,H78FL and H78FH than in group OVX and it was increased significantly in group H86AL. 2 OVX caused a significant decrease in bone mass and AW/DW.Compared with group OVX,the bone mass density were higher in those treated groups.Bone mass density and AW/DW were increased significantly in group H86AL(P＜0.01,P＜0.05).3 The result of histomorphometry showed:Compared with group S,the levels of BV/TV,Tb.Th and Tb.N in group OVX were deseased significantly(P＜0.01),the level of Tb.Sp was increased significantly(P＜0.01).The levels of BV/TV,Tb.Th and Tb.N were higher in the treated groups than those in group OVX.Among those treated groups,it was group H86AL whose BV/TV increased more significantly(P＜0.05).Compared with group S,the tetracycline single or double labelled bone surfaces,mineral apposition rate just lightly increased in group OVX. In comparison with group OVX and S,the level of single labelled bone surfaces in group H86AL,increased significantly(P＜0.01).4 Compared with group O,bone mass and bone strength were remarkably increased in group H86AL.Convulsions The bone loss in OVX rats might be somehow prevented by the osteogenic growth peptide analogues H86A,H74F and H78F,whose effects were related with their dosage.Among these analogues,the effection of H86AL was better.