Hauptmann M, Wilson D F, Erecińska M
Biochem Pharmacol. 1985 Apr 15;34(8):1247-54. doi: 10.1016/0006-2952(85)90502-7.
The effects of ATP gamma S, a slowly hydrolyzable analogue of ATP, were investigated in the preparation of synaptosomes isolated from rat cerebral cortex. It was found that addition of [35S]ATP gamma S resulted in substantial magnesium-dependent incorporation of 35S into synaptosomal proteins which was prevented completely by ATP. The most prominently labeled polypeptides were those with apparent molecular weights of 100,000; 84,000; 74,000; 62,000; 55,000; 48,000; and 41,000. The rate and extent of thiophosphorylation were unaffected by addition of cAMP, veratridine or sodium fluoride. ATP gamma S at 50-100 microM had no effect on either uptake or release of gamma-aminobutyric acid (GABA) and dopamine; at a concentration of 1 mM it inhibited incorporation of dopamine by about 20%. This inhibition was also seen with 1 mM GTP, beta, gamma-methylene-adenosine 5'-triphosphate and adenylylimidodiphosphate, which suggests that the nucleotide triphosphates themselves, and not membrane protein phosphorylation, were responsible for the effect observed. It is concluded that ATP gamma S is an effective tool for studying the possible role of ATP released in synaptic transmission. The results obtained thus far suggest that neither extrasynaptosomal ATP nor phosphorylation of external proteins of the presynaptic membrane is sufficient for modulation of neurotransmitter uptake or release. They may, however, play a role in combination with other conditions.
在从大鼠大脑皮层分离出的突触体标本中，研究了ATP的缓慢水解类似物ATPγS的作用。发现添加[35S]ATPγS会导致35S在镁离子依赖的情况下大量掺入突触体蛋白中，而ATP可完全阻止这种掺入。最显著标记的多肽是那些表观分子量为100,000、84,000、74,000、62,000、55,000、48,000和41,000的多肽。硫代磷酸化的速率和程度不受cAMP、藜芦碱或氟化钠添加的影响。50 - 100微摩尔的ATPγS对γ-氨基丁酸（GABA）和多巴胺的摄取或释放均无影响；在1毫摩尔的浓度下，它会使多巴胺的掺入量抑制约20%。1毫摩尔的GTP、β,γ-亚甲基腺苷5'-三磷酸和腺苷亚氨基二磷酸也出现这种抑制作用，这表明是三磷酸核苷酸本身，而非膜蛋白磷酸化，导致了所观察到的效应。结论是，ATPγS是研究突触传递中释放的ATP可能作用的有效工具。目前获得的结果表明，突触体外的ATP和突触前膜外部蛋白的磷酸化都不足以调节神经递质的摄取或释放。然而，它们可能与其他条件共同发挥作用。
