Seifert J, Sebestová L, Masek K
Institute of Pharmacology, Czechoslovak Academy of Sciences, Prague.
Int J Immunopharmacol. 1988;10(1):67-72. doi: 10.1016/0192-0561(88)90152-x.
The administration of muramyl dipeptide (MDP) in a single dose of 2 mg/kg increased markedly the utilization of 3H-thymidine for the synthesis of DNA thymine in liver, kidney and thymus, while no effect has been observed in spleen. Higher doses of MDP (5 mg and 10 mg) did not further increase the effect, but, on the contrary, in some tissues such as thymus, the effect was abolished. The repeated administration of 1 mg/kg of MDP for 7 days, contrary to single administration, had no effects. The measurement of proliferation activity in the experiment where DNA in the organs has been previously labeled with 3H-thymidine, has shown that the repeated administration of MDP (1 mg/kg) led to a more rapid decay in specific activity of DNA thymine in liver, kidney and thymus, but no effect was seen in spleen. The activities of thymidine kinase in the cytosole fraction of thymus and spleen after a single administration of MDP (1 mg/kg), are influenced in different ways. While in thymus the enzyme activity increased between 16 and 24 h, not being markedly changed in the early intervals, in spleen a significant decrease in phosphorylation of 14C-thymidine can be observed as early as 2 h after administration, and the decrease persists up to 48 h.
以2毫克/千克的单剂量给予胞壁酰二肽（MDP），可显著提高肝脏、肾脏和胸腺中用于合成DNA胸腺嘧啶的3H-胸腺嘧啶核苷的利用率，而在脾脏中未观察到任何影响。更高剂量的MDP（5毫克和10毫克）并未进一步增强这种作用，相反，在某些组织如胸腺中，这种作用被消除。与单次给药相反，以1毫克/千克的剂量重复给予MDP 7天没有效果。在先前用3H-胸腺嘧啶核苷标记器官中的DNA的实验中，对增殖活性的测量表明，重复给予MDP（1毫克/千克）导致肝脏、肾脏和胸腺中DNA胸腺嘧啶的比活性更快下降，但在脾脏中未观察到影响。单次给予MDP（1毫克/千克）后，胸腺和脾脏胞质部分中的胸苷激酶活性受到不同方式的影响。在胸腺中，酶活性在16至24小时之间增加，在早期阶段没有明显变化，而在脾脏中，早在给药后2小时就可观察到14C-胸苷磷酸化显著降低，并且这种降低持续至48小时。
