Effect Of Hemokinin-1 Analogues On Improving Sperm Vitality

Tachykinin (Tachykinins, TKs) is one of the largest peptide family, which is widely distributed in mammalians and non mammalians. Tachykinin which was found in mammals include:substance P (Substance P), neurokinin A(Neurokinin A NKA), neurokinin B (Neurokinin B NKB) and neuropeptide K (Neuropeptide K). In the past decades, researchers found only several kinds of tachykinin from mammals as SP, NKA and NKB. In contrast, about 40 tachykinin were found from nonmammals. In 2000, researchers found a new member of the tachykinin family-Hemokini-I in mouse hematopoietic cells. The precursor protein contains 128 amino acid whose sequences are KRSRTRQFYGLMGKR. The presence of FXGLM-NH2 is the marker of tachykinin. The left and right sides of the presence of K and R of two alkaline amino acid enzyme sites can be cut by pair of basic amino acid prohormone convertase. Subsequently, carboxypeptidase remove double base residues in the C-terminal, and C-terminalnear the glycine can be glycine peptide based acetylation amidation, get the mouse Hemokinin-1 eleven peptide aC-terminal amidating(mouse HK-1).The present study of the pharmacological effects of tachykinin HK-1 concentrated in the following aspects:①reproduction;②stimulation of nonpregnant women uterine contraction; ③immune regulation and inflammation;④cardiovascular system activity;⑤pain modulation;⑥antibacterial activity. Notably, the effect of HK-1 on the reproductive system, especially on the sperm motility is rarely reported. In our previous study, researchers successfully obtained 4 different Hemokinin-1 using multiphase solid state syntheses. They are HK-1(1-7), HK-1(1-8), HK-1(1-9) and HK-1(1-10). In the present study, the effect of HK-1(1-7),HK-1(1-8),HK-1(1-9) and HK-1(1-10) on human sperm motility was examined in the asthenospermia patients. The results shows that HK-1(1-7), HK-1(1-8), HK-1(1-9) and HK-1(1-10) have no effect on the percentage of sperms of a and b grade (P>0.05). Therefore, tachykinin peptide analogs losing carbon end have no effect on sperm motility. In conclusion, the carbon end of tachykinin peptide analogs is important for sperm motility.