Liu Lei, Shi Sa, Li Hong-Zhu, Li Hong, Xu Chang-Qing
Department of Pathophysiology, Harbin Medical University, Harbin 150086, China.
Zhongguo Ying Yong Sheng Li Xue Za Zhi. 2016 Mar 8;32(3):274-277. doi: 10.13459/j.cnki.cjap.2016.03.022.
To study the effect of excited dopamine type I receptor on the production of nitric oxide/nitric oxide synthase(NO/NOS)in ox-LDL activated THP-1 cells and the possible mechanism.
Cultured THP-1 cells activated by PMA were randomly assigned in the following groups:control group (control), oxidized low density lipoprotein group (ox-LDL), dopamine receptor 1(DR1) agonist group (SKF), DR1 antagonist group (SCH), ERK blocker group (PD98059). Oil Red O staining was used to identify the accumulation of cellular lipid. The levels of NO and NOS in the supernatant of THP-1 were assayed by nitrate reductase method. The protein expression of DR1, p-ERK and ERK were obtained by Western blot and immunity fluorescence.
After 48 h of incubation of ox-LDL, accumulation of lipid in the cytoplasm was found in most THP-1 cells. Compared with control group, DR1 protein expression was reduced in ox-LDL-induced cells(<0.01). Activation of DR1 agonist decrease the production of NO and iNOS(<0.01), and PD98059 partly reversed the above effect.
Activation of DR1 can inhibit the production of NO/NOS in ox-LDL-induced THP-1 cells, which may be related with ERK pathway.
研究激活多巴胺I型受体对氧化型低密度脂蛋白（ox-LDL）激活的THP-1细胞中一氧化氮/一氧化氮合酶（NO/NOS）产生的影响及其可能机制。
将经佛波酯（PMA）激活的培养THP-1细胞随机分为以下几组：对照组（control）、氧化型低密度脂蛋白组（ox-LDL）、多巴胺受体1（DR1）激动剂组（SKF）、DR1拮抗剂组（SCH）、细胞外信号调节激酶（ERK）阻断剂组（PD98059）。采用油红O染色鉴定细胞内脂质蓄积情况。用硝酸还原酶法检测THP-1细胞培养上清液中NO和NOS水平。通过蛋白质免疫印迹法和免疫荧光法检测DR1、磷酸化ERK（p-ERK）和ERK的蛋白表达。
ox-LDL作用48 h后，多数THP-1细胞胞质内出现脂质蓄积。与对照组相比，ox-LDL诱导的细胞中DR1蛋白表达降低（<0.01）。DR1激动剂激活后可降低NO和诱导型一氧化氮合酶（iNOS）的产生（<0.01），且PD98059可部分逆转上述作用。
激活DR1可抑制ox-LDL诱导的THP-1细胞中NO/NOS的产生，其机制可能与ERK信号通路有关。
