慢性再生障碍性贫血患者红细胞PRPP合成酶及腺苷脱氨酶活性的观测

Phosphoribosylpyrophosphatesynthetaseandadenosinedeaminaseactivityinerythrocytesfrompatientswithchronicaplasticanemia

为探讨慢性再生障碍性贫血（慢性再障）患者红细胞能量代谢障碍的机制，采用离子对反相高效液相色谱法（ＩＰｒＨＰＬＣ）及分光光度法检测了１８例慢性再障患者外周血红细胞中５－磷酸核糖－１－焦磷酸（ＰＲＰＰ）合成酶及１７例慢性再障患者红细胞腺苷脱氨酶（ＡＤＡ）活性。与２８名正常人组结果（２．１９±０．６１μｍｏｌｍｉｎ－１ｇ－１Ｈｂ）对比，经方差分析证实三种病情不同患者的ＰＲＰＰ合成酶活性均呈明显差异（Ｆ＝４．２９；Ｐ＜０．０１），而ＡＤＡ活性差异无显著性。患者红细胞ＰＲＰＰ合成酶的活性降低，使合成嘌呤、嘧啶核苷酸的关键中间产物ＰＲＰＰ生成减少，损害了腺嘌呤核苷酸的补救合成途径，从而导致红细胞内腺苷酸池水平下降。

Toexplorethemechanismoferythrocyteenergymetabolisminchronicaplasticanemia(CAA)patients,phosphoribosylpyrophosphate(PRPP)synthetaseandadenosinedeaminase(ADA)ac-tivitiesinerythrocytesfromCAApatientsweredeterminedbyion-pairreversed-phasehigh-performanceliquidchromatography(IPrHPLC)andspectrophotometry,respectively.VarianceanalysisindicatedthatthePRPPsynthetaseactivityinerythrocytesof18CAApatientsweresignificantlydiferentfromthatof28healthysubjects(F=4.29;P<0.01),whiletheADAactivityinerythrocytesfrom17CAApatientsshowednodiferenceincomparisonwiththe20healthysubjects.OurresultssuggestthatadecreaseinPRPPsynthetaseactivityleadtotheimpairmentofPRPPformationwhichdecreaseskeyintermediatesforthesynthesisofbothadenineandpyridinenucleotides,consequentlyinterferingthesalvagepathwayofadeninenucleotides.ThismayexplainthepossiblemechanismforthedecreaseofadenylatepoolinerythrocytesfrompatientswithCAA.