Research On The Antihypertensive Effect And3Endothelial Vasoconstrictor Factors Of Peptides Derived From Swine Femoral Head Collagenon

In order to verify the antihypertensive effect of collagen polypeptides from different parts of pig femur, learn their antihypertensive mechanism, fresh porcine femurs were taken as materials and collagen peptides of the whole swine femur, femoral shaft and femoral head separately(molecular weight<5ku)were prepared. Their ACE inhibitory activity were tested. Single and continuous intragastric experiments were taken, and the effects on3endothelial vasoconstrictor factors of femoral head collagen peptides were researched. The results showed as follows:(1)The IC50on ACE of the femur sample and the femoral head sample were respectively3.55mg/mL and2.05mg/mL. Hydrolysates of different parts ofpig femurhydrolysates can effectively inhibit the activity of ACE in vitro.(2)Single intragastric experiments with the whole swine femur and femoral shaft collagen peptides on SHRs wereindicated that either of them had any significant antihypertensive effect.They were abandoned in the subsequent continuous intragastric experiment.(3)Single intragastric experiments with collagen peptises from femoral head on SHRs indicated that this collagen polypeptide had a significant effect on decreasing systolic pressure.(4)Continuous intragastric experiment indicated that the heart rate of both SHRs and SD rats remained in the normal range. SD rats’systolic pressure were stable and no obvious reduction happened. So continuous intragastric administration of femoral head collagen polypeptide has no effect on rat blood pressure. Systolic blood pressures were significantly decreased in the3dose groups, and the onset is faster than that in captopril control group.30mg/kg.ig was the best dose in decreasing blood pressure.(5)Plasma concentrations ofthree endothelium-contracting factors and their precursors and synthesis were tested, and the results showed that collagen polypeptide from femoral head can obstruct the synthesis of Ang II and ET-1through inhibiting activity of ACE and ECE in certain concentration. While when in a high concentration of peptide, contents of Ang II and ET-1will increase. The effect of this peptide on TXA2is not obvious.