Mojsilović L, Zivković R, Kostić M
Bilt Hematol Transfuz. 1981;9(1-3):53-9.
In human red blood cell there is complete adenyl cyclase--cAMP system. However, the role of this system and its connection with energy metabolism in red cell is not known. Hence, we studied the effects of cAMP and DB-cAMP on energy metabolism in human red cell. Blood was taken out from haematologically healthy volunteers. Red cells were isolated by differential centrifugation and washed three times in Tris-Ringer buffer (pH 7.4). The red cells suspensions (in the above buffer) were simultaneously incubated without additions (control) and with cAMP or DB-cAMP (5 mmol/L). Incubation temperature was 37 degrees C. The samples of suspensions for the extraction of metabolites and cofactors were taken at 0 and 180 minutes of incubation. The lactate, glucose, G6P, F6P, TP, ATP, ADP and AMP were determined in neutralized perchloric acid extracts by specific enzymatic methods. Results of our experiments show that cAMP and DB-cAMP significantly increase red cell glycolysis. Under the same conditions these nucleotides induce positive "cros-over" point at the phosphofructokinase (PFK) step of the glycolysis. The levels of adenine nucleotides (ATP, ADP, AMP) were unchanged through a whole period of incubation. We concluded that cAMP and DB-cAMP stimulates glycolytic process in red cells probably by allosteric activation of PFK.
在人类红细胞中存在完整的腺苷酸环化酶 - 环磷酸腺苷（cAMP）系统。然而，该系统在红细胞中的作用及其与能量代谢的联系尚不清楚。因此，我们研究了cAMP和双丁酰环磷腺苷（DB - cAMP）对人类红细胞能量代谢的影响。从血液学健康的志愿者身上采集血液。通过差速离心分离红细胞，并在Tris - 林格缓冲液（pH 7.4）中洗涤三次。将红细胞悬液（在上述缓冲液中）同时在不添加任何物质（对照）以及添加cAMP或DB - cAMP（5 mmol/L）的情况下进行孵育。孵育温度为37摄氏度。在孵育0分钟和180分钟时采集用于提取代谢物和辅助因子的悬液样本。通过特定的酶法测定中和后的高氯酸提取物中的乳酸、葡萄糖、6 - 磷酸葡萄糖（G6P）、6 - 磷酸果糖（F6P）、三磷酸甘油醛（TP）、三磷酸腺苷（ATP）、二磷酸腺苷（ADP）和一磷酸腺苷（AMP）。我们的实验结果表明，cAMP和DB - cAMP显著增加红细胞糖酵解。在相同条件下，这些核苷酸在糖酵解的磷酸果糖激酶（PFK）步骤诱导出正的“交叉点”。在整个孵育期间，腺嘌呤核苷酸（ATP、ADP、AMP）的水平没有变化。我们得出结论，cAMP和DB - cAMP可能通过对PFK的变构激活来刺激红细胞中的糖酵解过程。
