Ofori S, Magistretti P J, Schorderet M
J Neurochem. 1986 Oct;47(4):1207-13. doi: 10.1111/j.1471-4159.1986.tb00741.x.
The modulation of 3,4-dihydroxyphenylethylamine (dopamine, DA) synthesis and release in rabbit retina in vitro by high K+; adenylate cyclase activators such as forskolin, 2-chloroadenosine, vasoactive intestinal polypeptide (VIP); and the putative DA autoreceptor agonist N-n-propyl-3-(3-hydroxyphenyl) piperidine (3-PPP) has been investigated. Incubation of retinas in 50 mM K+ resulted in the activation of tyrosine hydroxylase (TH). Activation did not require the presence of extracellular Ca2+. K+ 50 mM also induced a Ca2+-dependent release of DA. Forskolin 50 microM stimulated TH but 100 microM 2-chloroadenosine and 650 nM VIP did not. Individually, (+)-3-PPP, (-)-3-PPP, and (+/-)-3-PPP reduced DA synthesis and increased its release. The effects of (+/-)-3-PPP were dose-dependent and did not require the presence of extracellular Ca2+. The activation of TH induced by 50 mM K+, but not that induced by 50 microM forskolin, was abolished by 100 microM (+/-)-3-PPP.
研究了高钾、腺苷酸环化酶激活剂（如福斯高林、2-氯腺苷、血管活性肠肽（VIP））以及假定的多巴胺自身受体激动剂N-正丙基-3-(3-羟苯基)哌啶（3-PPP）对体外培养的兔视网膜中3,4-二羟基苯乙胺（多巴胺，DA）合成和释放的调节作用。将视网膜置于50 mM钾溶液中孵育可导致酪氨酸羟化酶（TH）激活。该激活不需要细胞外钙的存在。50 mM钾还诱导了钙依赖性的多巴胺释放。50 μM福斯高林刺激了TH，但100 μM 2-氯腺苷和650 nM VIP未起作用。单独使用时，(+)-3-PPP、(-)-3-PPP和(+/-)-3-PPP均可减少多巴胺合成并增加其释放。(+/-)-3-PPP的作用具有剂量依赖性，且不需要细胞外钙的存在。100 μM(+/-)-3-PPP可消除50 mM钾诱导的TH激活，但不能消除50 μM福斯高林诱导的TH激活。
