大鼠不同时期乳腺组织及血液中催乳素变化规律

The level of PRL in serum and mammary tissue during all stages of mammary development

为探讨催乳素在大鼠不同时期乳腺及血液中的变化规律,选择雌性SD大鼠42只,分别为处女鼠、妊娠鼠(6 d、12 d、18 d)、泌乳鼠(6 d、12 d、18 d),每个时期6只。在指定的时间点处死大鼠取乳腺组织及血清。用放免法对催乳素表达的变化进行定量研究,用统计学方法进行处理,观察催乳素的变化规律。结果显示,血清PRL水平以处女期最高,妊娠开始急剧下降,随着妊娠进行又逐渐增加,分娩后随着泌乳进行期渐渐下降。处女期与其余各期差异显著(P<0.05),整个妊娠期间以妊娠18 d为最高,且妊娠期间差异不显著(P>0.05),泌乳6 d明显高于泌乳12 d、18 d(P<0.05),泌乳12 d、18 d明显低于妊娠各期水平(P<0.05)。乳腺PRL变化模式与血清的变化不一致,处女期最高,随妊娠下降,泌乳期相对稳定,变化不大。处女期与其余各期差异显著(P<0.05),妊娠6 d水平仅明显低于处女期(P<0.05),而显著高于其余各期(P<0.05)。表明催乳素不仅参与了乳腺细胞的发育,而且在维持和启动泌乳方面也起到重要的作用。

To study the level of PRL in serum and mammary tissue during all stages of mammary development,fourty-two Sprague-Dawley female rats were used,Virgin,days 6,12,18 of pregnancy,days 6,12,18 of lactation.Each group had six rats.At designated time the serum and inguinal mammary glands were excised,frozen immediately,and stored at-80°C till use.We studied the level of PRL in serum and mammary tissue during all stages of mammary development.PRL expression decreased as pregnancy and lactation in serum（P0.05）.During the whole pregnancy period,PRL level at day 18 of pregnancy were much higher than that of day 6 and 12 of pregnancy.During the whole lactation period PRL level at day 6 of lactation were much higher than that of day 12 and 18of lactation（P0.05）.In mammary tissue,PRL level of virgin were the highest than others periods（P0.05）.PRL level at day 6 of pregnancy were much higher than that of day 12 and 18of pregnancy and the whole lactation（P0.05）.The results sugggest that PRL is involved in mammary development and start lactation.