五肽胃泌素对体外原代培养牛瘤胃上皮细胞DNA合成的影响

Effect of pentagastrin on rumen epithelial DNA synthesis in vitro

采用3 H -TdR掺入法 ,分 3个系列分别研究了不同剂量五肽胃泌素 ( pentagastrin)对体外原代培养的牛瘤胃上皮细胞DNA合成的影响 ,五肽胃泌素受体拮抗剂丙谷胺对五肽胃泌素营养作用的影响 ,以及五肽胃泌素对新生奶公牛瘤胃上皮细胞DNA合成的影响。结果如下 :1)用终浓度 10 -11,10 -10 和 10 -9mol·L-1的五肽胃泌素分别处理成年奶牛瘤胃上皮细胞 ,使3 H -TdR掺入量增加 30 4 2 % ,2 4 2 6 %和 4 7 16 % (P <0 0 5 ,n =3) ;在 10 -12 ,10 -11,10 -10 和 10 -9mol·L-1的五肽胃泌素作用下 ,成年黄牛瘤胃上皮细胞3 H -TdR掺入量提高了 34 2 5 % ,2 7 6 4 % ,2 6 4 7%和 39 0 8%(P <0 0 5 ,n =3) ;在 10 -12 ～ 10 -9mol·L-1范围内 ,3 H -TdR掺入量随五肽胃泌素剂量增加而呈上升趋势 ;在 10 -8mol·L-1时 ,3 H -TdR掺入量出现下降。 2 ) 10 -12 ,10 -11,10 -10 和 10 -9mol·L-1的五肽胃泌素均增加奶牛瘤胃上皮细胞3 H -TdR的掺入 (P <0 0 5 ) ,CCK 2 /gastrin受体拮抗剂丙谷胺抑制五肽胃泌素的营养作用。 3)用 10 -10 mol·L-1五肽胃泌素处理新生奶公牛瘤胃上皮细胞 ,未见其促进3 H -TdR掺入的作用。以上结果表明 ,胃泌素促进成年牛瘤胃上皮细胞DNA合成 。

The effects of pentagastrin on DNA synthesis of rumen epithelial,determined by 3H TdR incorporation,were conducted through three series of trials:Series Ⅰ,effect of pentagastrin on rumen epithelial DNA synthesis in adult cow and cattle treated with 4 different dosages;Series Ⅱ,effect of CCK 2/gastrin antagonist,proglumide,on trophic action of pentagastrin in adult cows;Series Ⅲ,effect of pentagastrin on rumen epithelial DNA synthesis in neonatal cow.The results showed:1)Pentagastrin(10 -11 , 10 -10 and 10 -9 mol·L -1 )increased the 3H-TdR incorporation into rumen epithelial cells by 30 42%, 24 26% and 47 16%( P <0 05)in adult cows respectively.And,doses of 10 -12 , 10 -11 , 10 -10 and 10 -9 mol·L -1 of pentagastrin enhanced the 3H TdR incorporated into rumen epithelial cells of cattle by 34 25%,27 64%,26 47% and 39 08%( P <0 05),respectively.Taking together,pentagastrin at the doses from 10 -12 to 10 -9 mol·L -1 exerted a dose dependent effect on rumen epithelial cell DNA synthesis,but not for dose of 10 -8 mol·L -1 .2) 3H TdR incorporation was higher in all pentagastrin treatments(10 -12 , 10 -11 ,10 -10 and 10 -9 mol·L -1 ),except the group treated with pentagastrin(10 -12 mol·L -1 )and proglumide(10 -8 mol ·L -1 )synchronously,in which the stimulation of pentagastrin on DNA synthesis was inhibited by proglumide.3)The rumen epithelial cells in neonatal cow were failure in response to pentagastrin at the dose of 10 -10 mol·L -1 .The data showed that pentagastrin promotes the rumen epithelial cell DNA synthesis in adult cattle.This effect of pentagastrin on rumen epithelium could probably be mediated by gastrin receptor located in rumen epithelium.The rumen epithelial cells in neonatal cow didn′t response to pentagastrin.