5'-N-Ethylcarboxamidoadenosine (NECA) is an agonist of Adenosine receptor, increases cerebral extravasation of fluorescein and low molecular weight dextran independent of blood-brain barrier modulation.

在体外培养的产Epo肝细胞癌（Hep3B）细胞系中，使用5'-N-Ethylcarboxamidoadenosine（≥10(-6)M）处理20小时于低氧条件下（1% O2），与低氧对照组相比，培养基中的Epo水平显著增加。在低氧环境中，以10(-7)M至5 x 10(-5)M浓度范围的5'-N-Ethylcarboxamidoadenosine处理肝细胞癌细胞1小时，其cAMP水平也显著高于低氧对照组。对肝细胞癌细胞膜制备进行的[3H]5'-N-Ethylcarboxamidoadenosine结合的Scatchard分析显示，低亲和力结合位点的解离常数（Kd）为0.44 μM，结合能力为863fM/mg蛋白。这表明，5'-N-Ethylcarboxamidoadenosine在低氧条件下促进Epo产生的增加，至少部分可以归因于刺激与腺苷酸环化酶激活相耦合的腺苷A2受体。

5'-N-Ethylcarboxamidoadenosine，一种腺苷类似物，对红细胞生成素(Epo)的生产有影响。5'-N-Ethylcarboxamidoadenosine（分别为0.05和0.1 mumol/kg i.v.）在缺氧后的多血红蛋白小鼠体内，通过四小时的低氧暴露，显著提高了血清Epo水平（分别为368.8 +/- 56.1和384.6 +/- 45.9 mU/ml），与低氧对照组（133.2 +/- 18.2 mU/ml）相比有显著差异。低氧状态下的肾脏Epo水平为46.4 +/- 13.4 mU/kg肾脏，明显高于常氧肾脏Ep水平（< 1.24 mU/kg肾脏）。茶碱（20 mg/kg i.p.），一种腺苷受体拮抗剂，显著抑制了5'-N-Ethylcarboxamidoadenosine对血清Epo水平的刺激效果[1]。

A human hepatocellular carcinoma cell line (Hep3B) was employed to determine the in vitro effects of NECA on Epo production and cAMP accumulation. Hep3B cells were carried in a monolayer cell culture and maintained in 75 cm^2 Corning culture flasks containing Eagle's minimal essential medium (MEM) supplemented with 10% fetal bovine serum (PBS), 0.1 m nonessential amino acids, 1 m sodium pyruvate, 100 U/ml penicillin G, and 100 μg/ml streptomycin in a humidified atmosphere of 5% C02/95% air at 37℃. The culture medium was replaced every two days. Cells were detached with trypsin and aliquots of 2.5 x 10^5 viable cells (determined by trypan blue dye exclusion) were transferred to 24 multi-well plates. Each experiment was carried out with low density cells before they reached confluency. The cells were incubated with NECA in concentrations of 1O^9 M to 5 x l0^-5 M in the presence of 1 U/ml adenosine deaminase (ADA) under hypoxic conditions (1% 02, 5% C02, and 94% N2) for 20 hours following 24 hour preincubation in a normoxic atmosphere. At the end of the incubation period, the supernatant was harvested and frozen at -70℃ prior to Epo RIA. The multiple-range test of Duncan was used for the comparison of the several in vitro treatment groups compared with controls[1].