The Effects Of Oyster Active Peptides On Sexual Behavior And Reproductive Function Of D-galactose Induced Aging Male Rats

OBJECTIVE:To investigate the effects of oyster active peptides on sexual behavior and reproductive function of D-galactose induced aging male rats.METHOD:(1)Establishment of the animal aging model and groups100 SD rats(SPF degree,weight 320±20g)were used in this study,half male and half female.Male rats were randomly divided into 5 groups with 10 rats for each:normal group(N group),control group(C group),oyster peptide high dose group(H group),medium dose group(M group),low dose group(L group),with 10 female rats matching each group.After adjusting to the environment,the normal group was given subcutaneous injection of 0.025ml/g·d-1 saline on the back of the neck,and the rest rats were subcutaneously injected with equal doses of 5%D-galactose solution for 8 weeks,which prepared in physiological saline.(2)Sexual behavior testSexual behavior test is performed after the model established.The male rats in normal group and control group were lavaged with physiological saline at dose of 10 ml/kg·d-1.The H group,M group,and L group were respectively lavaged with Oyster Peptide at doses of 500 mg/kg·d-1,250 mg/kg·d-1,and 125 mg/kg·d-1,for 4 weeks.Before the sexual behavior test,Each female rat was injected subcutaneously with estradiol benzoate to make the estrus period the same.After 30 minutes of dosing,males and females were paired into individual cages,On days 0,7,14,and 28.Sexual behavior was observed and recorded,including mount latency,mount frequencies,ejaculation times,ejaculation latency.(3)Biochemical indicator testAfter the end of the sexual behavior test,male rats with 1%sodium pentobarbital solution anesthesia,through the inferior vena cava to collect blood,centrifuged supernatant obtained.The concentration of testosterone and zinc in the serum to be tested was determined by ELISA kit,and through the similar method to measure the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and catalase(CAT).In addition,taking a certain amount of testicular tissue,homogenate in ice bath,and then centrifugation to obtain supernatant.determine the concentration of stem cell factor(SCF),and the activity of SOD,GSH-Px and CAT by ELISA kit.(4)Histomorphology:while blood was taken from inferior vena cava,testis and epididymis were separated and taken.Permanent sections prepared from testicular tissue,HE staining,was observed and recorded histomorphology.Another amount of testicular tissue was taken,homogenized by SMT(saline-merthiolatetriton)solution.observe sperm under a light microscope,and calculate the daily sperm production per gram of testis.The caudal epididymis was cut and incubated at 37? in normal saline to prepare spermatozoa suspension.The sperm viability and sperm deformity rate were observed and calculated by HE staining.RESULT:(1)In addition to the normal group,the other rats gradually developed aging status.(2)Oyster peptide can shorten the mount latency,increase the mount frequencies,the ejaculation times and the ejaculation latency of D-galactose-induced aging male rats.(3)Oyster peptide could increase the levels of zinc and testosterone in serum,the levels of SOD,GSH-Px and CAT in serum and testis homogenate,and the level of SCF in testis homogenate of D-galactose-induced aging male rats.(4)Oyster peptide can improve the symptoms of testicular atrophy of D-galactose-induced aging male rats,repair structural damage of seminiferous tubule epithelium,induce the apoptosis of germ cells,sertoli cells and Leydig cells;increase the number of sperm,sperm viability and daily sperm production reduce sperm abnormality.(5)In the experiment,all the data of the H group were significant difference between from the control group(p<0.05).CONCLUSION:Oyster peptides have a repairing effect on the sexual behavior and reproductive function of D-galactose-induced aging male rats,and can improve the state of reproductive aging at multiple levels.