The Study On The Softening And Dilating Mechanism Of The Mature Cervix During The Parturient Period Of Goat

Cervix is an important organ that maintains gravidity and carries out the delivery in the female animal, and its change has an important effect on entire gravidity process. Cervix is composed of epithelium, connective tissue (85%~90%), smooth muscle (10%~15%) and glandular organ etc. Connective tissue contains copious collagen fibers, a little elastic fibers and reticular fibers, and the changes of these fibers are concerned with cervix stiffness degree,cervix opening and shutting. The change of matrix constituent is concerned with cervix softening. The proportion of diverse component is different as advancing pregnancy, for example, the collagen fiber constitute primary element during the early period of gestation, so the cervix with certain elasticity and tenacity can maintain gravidity. A series of the cervical changes in anatomy and physiology appear to adapt delivery prior to parturition,such as the cervical softening,effacement and dilatation, decrease of cervical collagen and glucoseamine, and increase of moisture content and so on, so the process is called cervical ripening. Cervical ripening is the critical process determining the success or failure of inducing labour, the duration of the labour, the easiness of the dilivery.Cervical ripening is not only a active biochemistry process, but also a inflammatory reaction as there are a lot of media have participate in cervical ripening, such as progesterone, prostaglandin, relaxin, cytokine and NO etc., but it is a little known about the regulation to the process of cervical ripening at present. Experimentâ… :The change in the level of hormones and cytokines in peripheral blood during the labour in goatsThe serum levels of PGE2, P4, E2, IL-1 and IL-8 during the peripartum period of the goat are determined to study their role in the delivery process and their effect on the cervical ripening.36 seria of goats(n=8) during the peripartum and parturient period are sampled to determine the level of PGE2 by ELISA and P4, E2, IL-1 and IL-8 by RIA .The prepartum serum level of PGE2,E2,IL-1 and IL-8 are gradually rising, one day before parturition the numbers of the parts are 481.034pg/mL,60.304pg/mL,0.283ng/mL,0.240ng/mL, and then gradually decreasing to 268.382pg/mL,52.706 pg/mL,0.233ng/mL,0.189ng/mL after parturition. The level of PGE2 reaches the climax to 740.964pg/mL at the beginning of the parturition, and the level of E2 increases to the climax to 94.354pg/mL during the period of the parturition, and then decrease to the lowest level after parturition; The level of P4 is gradually decreasing during the later period of the parturition, at the day before parturition the level of P4 drop to 16.686ng/mL, and then decrease significantly to 1.871ng/mL.PGE2,P4,E2,IL-1 and IL-8 play important part in the process of the cervix ripening during the pregnant period. Although the P4 can inhibit the maturation, it has enhancement in the maturation of the cervix when P4 is significantly decreasing during the later period of the parturition, so it has an important regulatory function in the maturation of the cervix.Experimentâ…¡:The comparative observation of frozen sections of cervix in labour and nonpregnancy and greater omentum and adipose tissues in goats The healthy goats close to labour (n=8) are at random selected and fed , and the samples at the anterior,midst and posterior part of the cervix are collected on operation at the second stage of labor or collected immediately after the expulsion of a fetus. The samples of greater omentum and fatty tissue can be collected from one of the healthy goats.The samples should be put into the nitrogen container with liquid nitrogen after collection, and can be sliced 12 to 24 hours after the cryoultramicrotome work. The staining solution is Sudanâ…¢or Oil red.A great many of orange-red-stained adipose cells in greater omentum and adipose tissues can be observed under microscope,and a few of orange-red-stained adipose droplets or cells in the cervical tissues are also observed which improve the degree of cervical softening and provide the essential energy for cervical opening. Experimentâ…¢: The preparation and analysis of transmission electron microscope sections of cervix in labour in goatsThe healthy goats close to labour (n=8) are at random selected and fed , and the samples at the anterior,midst and posterior part of the cervix are collected on operation during the second stage of labor or collected immediately after the expulsion of a fetus.The samples should be first fixed with 3.5% glutaraldehyde and washed with PBS, then fixed with osmic acid and washed with PBS, then dehydrated with different gradient of alcohol, finally soaked and embedded with spur resin, sliced, stained and observed.There exist a lot of substance like adipose cells in some blood vessel of cervix and many adipose droplets in cells of cervix in labor under transmission electron microscope, In addition, breakthrough of cell wall, release of adipose droplets into tissues, edema of cervical tissues, rupture of mitochondria and production of foreign body occur.The results above indict that the substance like adipose cells and adipose droplets are energy origin for cervical dilation and edema and rupture of mitochondria is one process for cervical softening and ripening.