Paes-de-Carvalho R, Maia G A, Ferreira J M
Department of Neurobiology and Program of Neuroimmunology, Institute of Biology, Federal Fluminense University, Niterói, RJ 24001-970, Brazil.
Neurochem Res. 2003 Oct;28(10):1583-90. doi: 10.1023/a:1025686812298.
Adenosine modulates the survival of chick embryo retinal neurons in culture. When cultures were incubated for 3 days and refed with fresh medium, a large proportion of neurons died in the subsequent 3 days of culture. This cell death was prevented by preincubation of cultures for at least 24 h with adenosine plus the adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA), an adenosine uptake blocker nitrobenzylthioinosine (NBI), the adenosine A2A receptor agonist 2-[4-(2-carboxyethyl) phenethylamino]-5'-N-ethylcarboxamidoadenosine (CGS21680), or the permeant cyclic AMP analog 8-bromo cyclic AMP, but not the A1 receptor agonist cyclohexyladenosine (CHA). Adenosine deaminase induced cell death when added to culture medium, and this effect was prevented by EHNA. Cell death was not observed when the medium was replaced by a conditioned medium from sister cultures. The data strongly suggest that adenosine regulates the survival of developing retinal neurons by a long-term activation of A2A receptors and the increase of cyclic AMP levels.
腺苷可调节培养的鸡胚视网膜神经元的存活。当培养物孵育3天并更换新鲜培养基后，大部分神经元在随后3天的培养过程中死亡。通过用腺苷加腺苷脱氨酶抑制剂erythro-9-(2-羟基-3-壬基)腺嘌呤（EHNA）、腺苷摄取阻滞剂硝基苄硫基肌苷（NBI）、腺苷A2A受体激动剂2-[4-(2-羧乙基)苯乙氨基]-5'-N-乙基羧酰胺腺苷（CGS21680）或渗透性环磷酸腺苷类似物8-溴环磷酸腺苷对培养物进行至少24小时的预孵育，可防止这种细胞死亡，但A1受体激动剂环己基腺苷（CHA）则不能。将腺苷脱氨酶添加到培养基中会诱导细胞死亡，而EHNA可防止这种作用。当用来自姐妹培养物的条件培养基替换培养基时，未观察到细胞死亡。数据强烈表明，腺苷通过长期激活A2A受体和提高环磷酸腺苷水平来调节发育中视网膜神经元的存活。
