Kedryna Teresa, Gumińska Maria, Lucyna Zamorska
Institute of Medical Biochemistry, Collegium Medicum, Jagiellonian University, Cracow, Poland.
Med Sci Monit. 2004 Dec;10(12):CR672-8.
It was shown earlier that in women living in a polluted environment, the proportion of hypotrophic newborns was greater than in the general population. The placentas of these women show significant histological changes. The authors decided to check whether the activity of pyruvate kinase (PK), a key enzyme in the third stage of glycolysis, changes similarly.
MATERIAL/METHODS: The study was conducted on placentas collected from women who had lived in a polluted environment (Groups I and II) and those who had inhabited an unpolluted area (Group III) while pregnant.
Total PK activity and the specific activities of its isoenzymes were measured according to the Bücher and Pfleiderer method. The isolation of PK isoenzymes was carried out following the previously described procedure. Total PK activity was lower in the placentas of women of Groups I and II than in those of Group III. The presence of two PK isoenzymes, M2 and L, was demonstrated. The M2 and L isoenzymes from the placentas of Groups I and II had a lower specific activity than those of Group III. Only one form of the M2 isoenzyme and the L dephospho-isoenzyme in the placentas from Groups I and II was observed, while in placentas of Group III women both forms of the M2 isoenzyme and the L phospho-isoenzyme were noted.
It is possible that the presence of the two PK isoenzymes in the placenta ensures the production of a sufficient amount of pyruvate.
早期研究表明，生活在污染环境中的女性所生低体重新生儿的比例高于一般人群。这些女性的胎盘显示出明显的组织学变化。作者决定检查糖酵解第三阶段的关键酶丙酮酸激酶（PK）的活性是否也有类似变化。
材料/方法：本研究对孕期生活在污染环境中的女性（第一组和第二组）以及居住在未污染地区的女性（第三组）的胎盘进行了研究。
根据比歇尔和普弗莱德雷尔方法测定了PK的总活性及其同工酶的比活性。按照先前描述的程序进行PK同工酶的分离。第一组和第二组女性胎盘的PK总活性低于第三组。证实存在两种PK同工酶，即M2和L。第一组和第二组胎盘的M2和L同工酶的比活性低于第三组。在第一组和第二组胎盘样本中仅观察到一种形式的M2同工酶和L去磷酸化同工酶，而在第三组女性的胎盘中则同时发现了两种形式的M2同工酶和L磷酸化同工酶。
胎盘中两种PK同工酶的存在可能确保产生足够量的丙酮酸。
