Distribution Of ERα, ERβ And PR And Expression Of Its MRNA In The Uterus Of Jining Grat Goats Associated With Aging

Jining Gray Goat is not only an excellent local goat species which is breed in China, butalso excellent germplasm resource in the world. Because of its early maturity, highreproduction rate, four seasons all can estrus, genetic stability, strong adaptability, fleshydelicate, delicious and other excellent characteristics, that Jining Gray Goat is favored by themajority of people. The puberty of ewes begin at60days of age and sexual maturity at90to120days of age. The objective of the experiment was to study the level of estrogen andprogesterone, the location of ERα、ERβ and PR and the expression in the uterus. Serumestrogen and progesterone content of Jining Gray goat born at0to180days of age stage wasmeasured by radioimmunoassay. The SABC methods were used to study the distribution ofERα, ERβ and PR proteins of different group in the uterus, the real time fluorescentquantitative PCR with GAPDH as an internal gene were used to research the relativeexpression of ERα mRNA, ERβ mRNA and PR mRNA in uterus during postnataldevelopment in Jining Gray Goat. Immunoradiometric analysis results showed that jininggray goat born at0to180days of age were to detect E and P, E content of serum wasdetected most on the birth day,30days of age which was significantly decreased(P<0.05).Although two peaks were found at90days of age and180days of age, little change duringthe60to180days of age (P>0.05). Higher serum P concentration was detected on the birthday, and thereafter decreased rapidly, but from day30to90day did not change significantly(P>0.05),120days of age had a sudden rise then no significant change (P>0.05),180days ofage had a sudden rise(P<0.01).Immunohistochemical results of ERα, ERβ and qRT-PCRresults showed that: ERα、ERβ and PR were mainly localized in the nuclei of the luminalepithelium, glandular epithelium, stromal cells, endothelium and smooth muscle cells of theuteru， and occasionally in the cytoplasm. The trends of the optical density in theimmunopositive cells of ERα, ERβ and PR were similar with that of the expression of ERαmRNA, ERβ mRNA and PR mRNA. But the expression of ERβ was less than ERα. From thebirth day to30days, the expression of ERα and ERβ remained at a lower level(P>0.05) then increased gradually at60days, From90days on, the expression of ERα and ERβ reached thepeak(P<0.05)and maintained at a high level. While the expression of PR was higher on thebirth day, then reached its lowest level on the30days and significantly increased after puberty,and two peaks were found during the sexual maturity and maturation then maintained at ahigh level. The expression of ERβ mRNA also remained at a lower level from the birth day to30days then increased gradually at60days, which reached the peak at90days of age andmaintained at a high level. The trends of the optical density in the immunopositive cells ofERα and ERβ were similar with that of the expression of ERα mRNA, ERβ mRNA and PRmRNA. But the expression of ERβ was less than ERα. Immunohistochemical results of PRand qRT PCR results showed that: PR was mainly localized in the nuclei of the luminalepithelium, glandular epithelium, stromal cells and myometrial cells of the uterus，andoccasionally in the cytoplasm. PR positive cells distribute in large quantities at180days ofage in the glandular epithelial cells. The trend of the optical density PR was higher on thebirth day, then decreased gradually, and reached its lowest level on the30days andsignificantly increased after puberty, on the120days reached the first peak,150days wasslightly lower, on the180days reached the second peak. The expression of PR mRNAremained at a lower level from the birth day to90days and there was no significant differenceduring these groups (P>0.05). The two peaks were found at120days and180days (P<0.01).The trend of the optical density PR was similar with that of the expression of PR mRNA. Theresults showed that: regular change of E, P and ERα, ERβ, PR in the uterus have an importantsupport materials in endocrine mechanism of sexual development and sexual precocity inJining Gray goats.