P物质对培养的大鼠腺垂体细胞cAMP含量的影响

THE EFFECT OF SUBSTANCE P ON THE CONTENT OF cAMP IN CULTURED ANTERIOR PITUITATY GLAND CELLS OF THE RAT

目的 :探讨 P物质 ( SP)与培养的大鼠腺垂体细胞 SP受体 ( SPR)结合后是否改变第二信使 c AMP的含量。方法 :取雌性间情期 S-D大鼠的腺垂体进行培养 ,实验设立对照组、 Forskolin ( FSK)组、 SP组 ,改变 SP的浓度和反应时间。应用 RIA法测定细胞内 c AMP的含量。结果 :短时间内 ( 2分钟 ) ,SP以浓度依赖的方式提高了初代培养的腺垂体细胞内基础 c AMP水平 ,最大反应发生在 SP浓度为 1 0 0 n M时 ,c AMP的含量为 ( 2 .58± 0 .1 4) pmol/4 .2 7× 1 0 5个细胞 / ml,是对照组的 2 2 2± 4 % ( P<0 .0 1 ,n=2 0 )。结论 :SP使初代培养的成年雌性间情期 S-D大鼠腺垂体细胞内基础 c AMP水平增高 ,提示 :SP兴奋腺垂体细胞 SPR后的生物学反应 ,至少部分是通过第二信使 c

Objective:The main idea of this study was to determine whether the effect of SP on SPR in anterior pituitary gland cells (AP) is mediated by the formation of second messenger cAMP .Methods:In our study,We chose adult female rats AP during dioestrus by vaginal smear to culture .They were divided into the control group,Forskolin (FSK,25μΜ)group and SP groups in study,changing the concentration of SP and reactive time.Intracellular cAMP was extracted from cell with 10% HClO 4 and determined by RIA.Results:SP increased the intracellular basal cAMP level in a concentration -dependent manner after a shorter stimulation period (2 minute).With increasing SP concentration from 10nM to 100nM,the content of cAMP increased to maximal value of 222±4%( P <0.01, n =20)of control group.SP concentratiom above 100nM induced diminished cAMP responses.Conclusion:SP increased intracellular basal cAMP level of the culturcd AP cells of adult female S D rats during dioestrus,suggesting that biological responses in AP cells following activation of SPR are mediated,at least in part,by the change of cAMP level.