Verhoeven A J, Mommersteeg M E, Akkerman J W
Biochem J. 1986 Jun 15;236(3):879-87. doi: 10.1042/bj2360879.
The correlation between energy consumption and platelet responses induced by collagen, A23187 and ADP was investigated and compared with the energetics of thrombin-stimulated platelets established in earlier work. Aggregation, measured as single-platelet disappearance, and secretion correlated quantitatively with the increment but not with the total consumption of energy, suggesting that the former reflects the energy cost of these responses. The cost of complete aggregation was 2-3 mumol of ATP equivalents/10(11) platelets with collagen, ADP and thrombin as the stimulus. The cost of complete dense-granule secretion was 0.5-0.8 mumol of ATP equivalents/10(11) platelets with all agonists tested. The cost of combined secretion of alpha-granule and acid hydrolase granule contents was 5-7 mumol of ATP equivalents/10(11) platelets with thrombin and collagen. However, in the presence of A23187 much more energy was consumed during aggregation and secretion. Also ADP triggered more energy consumption during secretion than was seen with the other inducers. The effect of inhibitors of aggregation and secretion was investigated in thrombin-stimulated platelets. Raising the cellular cyclic AMP content sharply decreased the increment in energy consumption as well as aggregation and secretion. The cytoskeleton-disrupting agents cytochalasin B and colchicine left the increment in energy consumption intact, but decreased the basal consumption seen in unstimulated platelets. This was accompanied by normal (cytochalasin B) or diminished (colchicine) aggregation and secretion. Apart from the latter exception, all inhibitors decreased secretion and incremental energy consumption in parallel, thereby preserving the energy-versus-secretion relationship established in earlier work. In contrast, aggregation and energy consumption varied independently, suggesting that the coupling with energy consumption is much weaker for this response.
研究了能量消耗与胶原蛋白、A23187和ADP诱导的血小板反应之间的相关性，并与早期工作中建立的凝血酶刺激血小板的能量学进行了比较。以单血小板消失来衡量的聚集以及分泌与能量增量在数量上相关，但与能量的总消耗量无关，这表明前者反映了这些反应的能量消耗成本。以胶原蛋白、ADP和凝血酶为刺激物时，完全聚集的成本为2 - 3微摩尔ATP当量/10¹¹个血小板。以所有测试的激动剂为刺激物时，致密颗粒完全分泌的成本为0.5 - 0.8微摩尔ATP当量/10¹¹个血小板。以凝血酶和胶原蛋白为刺激物时，α颗粒和酸性水解酶颗粒内容物联合分泌的成本为5 - 7微摩尔ATP当量/10¹¹个血小板。然而，在存在A23187的情况下，聚集和分泌过程中消耗的能量更多。此外，与其他诱导剂相比，ADP在分泌过程中引发的能量消耗更多。在凝血酶刺激的血小板中研究了聚集和分泌抑制剂的作用。提高细胞内的环磷酸腺苷含量会大幅降低能量消耗的增量以及聚集和分泌。破坏细胞骨架的药物细胞松弛素B和秋水仙素使能量消耗的增量保持不变，但降低了未刺激血小板中的基础消耗量。这伴随着正常（细胞松弛素B）或减少（秋水仙素）的聚集和分泌。除了后一个例外，所有抑制剂都平行降低了分泌和能量消耗的增量，从而保持了早期工作中建立的能量与分泌的关系。相比之下，聚集和能量消耗独立变化，这表明这种反应与能量消耗的耦合要弱得多。
