SNAP对大鼠生长激素腺瘤GH3细胞增殖、生长激素分泌的影响及机制探讨

目的观察一氧化氮(NO)释放剂S-亚硝基-N-乙酰青霉胺(SNAP)对大鼠生长激素(GH)腺瘤GH3细胞增殖、GH分泌的影响,并探讨其机制。方法将细胞分为A、B、C、D组,A组常规培养,B、C、D组分别加ghrelin、SNAP、SNAP+ghrelin培养。分别于培养第0、1、2、3、4、5、6天,用MTT法检测细胞吸光度值观察细胞增殖情况;培养2 h后,用ELISA法检测GH3细胞培养液中的GH,Western blot法检测GH3细胞中的磷酸化细胞外信号调节激酶(p-ERK)。结果 A组培养第2、3、4、5、6天时细胞吸光度值分别为0.381±0.006、1.664±0.005、3.411±0.005、5.221±0.005、10.055±0.005,B组分别为1.062±0.005、3.115±0.005、4.512±0.005、6.656±0.005、11.060±0.005,C组分别为0.161±0.006、0.413±0.005、0.931±0.005、1.861±0.005、5.612±0.005,D组分别为0.219±0.004、0.865±0.005、1.712±0.005、3.059±0.005、6.561±0.005;B组与A组、C组与A组、D组与B组比较,P均<0.01。培养2 h时,A、B、C、D组GH3细胞培养液的吸光度值分别为0.080±0.002、0.165±0.011、0.041±0.003、0.106±0.005,pERK表达量分别为0.301 8±0.004 5、0.682 5±0.003 8、0.192 3±0.008 6、0.298 5±0.006 7,B组与A组、C组与A组、D组与B组比较,P均<0.01。结论 SNAP可抑制ghrelin诱导的GH3细胞增殖及GH分泌,可能与其阻断ghrelin激活的ERK信号通路有关。

Effect and mechanism of SNAP on growth hormone secretion and cell proliferationin rat GH3 cells

Objective To obserbve the effects of S-nitroso-N-acetylpenicillamine(SNAP) on growth hormone(GH) secretion and cell proliferation in rat GH3 cells and explore the possible mechanism.Methods GH3 cells were divided into A,B,C,D group.GH3 cells in group A were cultured normally.GH3 cells in group B,C,D were cultured with ghrelin,SNAP,ghrelin+SNAP.After 0,1,2,3,4,5,6 d,MTT was used to detected the absorbance value.After cultured for 2 h,ELISA was used to detected the GH in GH3 cells culture solution;Western blot was used to detected the phospho-excelluar signal-regulated kinase(p-ERK) in GH3 cells.Results The absorbance value of GH3 cells cultured for 2,3,4,5,6 d in group A were 0.381±0.006,1.664±0.005,3.411±0.005,5.221±0.005,10.055±0.005;1.062±0.005,3.115±0.005,4.512±0.005,6.656±0.005,11.060±0.005 in group B;0.161±0.006,0.413±0.005,0.931±0.005,1.861±0.005,5.612±0.005 in group C;0.219±0.004,0.865±0.005,1.712±0.005,3.059±0.005,6.561±0.005 in group D.There were significant difference between the absorbance value of GH3 cells in group B and A,C and A,D and B(all P<0.01).The GH level in group A,B,C,D cultured for 2 h were 0.080±0.002,0.165±0.011,0.041±0.003,0.106±0.005;and the p-ERK were 0.301 8±0.004 5,0.682 5±0.003 8,0.192 3±0.008 6,0.298 5±0.006 7.There were significant difference between the GH level and p-ERK in GH3 cells in group B and A,C and A,D and B(all P<0.01).Conclusion SNAP reduces both basal and induced by ghrelin GH secretion and cell proliferation in rat GH3 cells via blocking ERK signaling pathway.