The Regulation Of Leptin In Rat Mammary Gland Development

To study the regulation of leptin in rat mammary gland development,this thesis selected virgin,pregnant,lactating rats as objection.We had studied the expression of Leptin and LeptinR in mammary gland,the level of Ieptin,leptinR in mammary gland during the virgin-pregnancy-lactation cycle in rat and also the corelation leptin in mammary to others hormone in mammary,by the RT-PCR and the radicalization immunity assay(RIA)methods.The results as follow:Seriesâ… The expression of leptin and leptinR mRNA in the rat mammary gland.The results showed that leptin and leptinR mRNA were expressed in the rat mammary g;land.Seriesâ…¡Leptin,leptinR mRNA level in the mammary during mammary development.The result showed:1,In mammary gland,leptin mRNA level was highest at virgin,decreased at the beginning of pregnancy,reached the bottom at day 18 of pregnancy,increased at the beginning of lactation,returned to the level in virgin at day 18 of lactation.Hint:leptin mRNA level in mammary tissues was positive related with the fat concentration in mammary gland.2,leptinR mRNA level in the mammary increased at the beginning of pregnancy,reached the top ar day 12 of pregnancy,then decreases day by day,decreased at the beginning of lactation,reached the bottom at day 12 of lactation,returned to the level in virgin at day 18 of lactation Hint:the change of leptinR mRNA level was similar to the change of the mammary duct development,leptin may promote the mammary duct development.3,the change of leptin level was not related to the change of leptinR level during the pregnancy-lactation.Hint:leptin acted through membrane receptors,leptin might not only from mammary tissues,but also from serum,moreover leptin level in mammary might regulate leptinR in mammary up and down.Seriesâ…¢The correlation leptin level in mammary to the hormones ofmarnmary development s during mammary development.The result showed:leptin level was positive related with the level of E2,P in mammary only duringthe pregnancy,leptin level was positive to the level of Prl GH during the pregnancy-lactation cycle Hint:leptin in mammary might promote the development of mammary duct and gland bubble with E2,P;leptin in mammary might promote the mammary development and start secretion of milk with Prl; leptin in mammary and GH were promoting the growth during mammary developmen,strengthen the action to promote the gland bubble development with Prl,mighe play an important role in the modulation of the mammary gland development.