孕牛血中cAMP、cGMP水平变化的测定

选择３０头妊娠奶牛，根据妊娠不同分为妊娠前期（＜１００ｄ）、妊娠中期（１００～２００ｄ）和妊娠后期（＞２００ｄ）３组，应用放射免疫法测定孕牛血浆和外周血单个核细胞（ＰＢＭＣ）的ｃＡＭＰ和ｃＧＭＰ的含量．结果表明：随着妊娠期延长，孕牛血清和单个核细胞的ｃＡＭＰ是逐渐减少，而ｃＧＭＰ则是逐渐升高，但与对照组相比差异不显著（Ｐ＞０．０５）；血浆中ｃＡＭＰｃＧＭＰ之比值均比对照组高且差异显著（Ｐ＜０．０５），但随妊娠期延长而逐渐下降．

The assay of blood cAMP and cGMP levels in pregnant dairy cows

Thirty　pregnant　dairy　cows　were　selected　from　a　dairy　herd　and　divided　into　3　　groups　according　to　different　gestation　stages:viz.　the　first　trimester　(less　than　100　days),the　middle　trimester　(100　to　200 days)　and　the　last　trimester(more　than　200 days).　Radioimmunoassay　was　used　to　determine　the　plasma　and　mononuclear　cell　cAMP　and　cGMP　levels　in　these　pregnant　dairy　cows.The　results　showed　that　the　longer　the　gestation　duration,　the　lower　the　levels　of　cAMP,but　the higher　the　levels　of　cGMP　in　plasma　and　mononuclear　cells.The　differences　between　3　groups　and　non-pregnant　dairy　cows　were　not　significant　(P>0.05).The　ratioe　of　plasma　cAMP　to　cGMP　in　pregnant　cows　was　obviously　higher　(P<0.[KG-4]05) than　that　in　non-pregnant　cows.However　as　the　gestation　duration　increased,　this　ratio　seemed　to　become　lower.