کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2537100 1559176 2006 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Tetrahydrobiopterin stimulates l-DOPA release from striatal tissue
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب سلولی و مولکولی
پیش نمایش صفحه اول مقاله
Tetrahydrobiopterin stimulates l-DOPA release from striatal tissue
چکیده انگلیسی

In the present study we have analyzed the effect of tetrahydrobiopterin (BH4) essential cofactor for tyrosine hydroxylase and nitric oxide synthase, on the 3,4-dihydroxyphenylalanine (l-DOPA) release from in vitro incubated striatal tissue. dl-6-methyl-5,6,7,8 tetrahydropterine (6-MPH4)-stimulated l-DOPA release in a concentration-dependent manner in the range from 25 to 100 μM. At these concentrations 6-MPH4 did not have any effect on dopamine release. Presence of Nω-Nitro-l-arginine methyl ester (l-NAME, 200 μM), a nitric oxide synthase inhibitor, but not of α-methyl-ρ-tyrosine (α-MPT, 100 μM), a tyrosine hydroxylase inhibitor, blocked l-DOPA release induced by 6-MPH4 (200 μM). Also, the addition to the incubation medium of melatonin (MEL, 300 μM), which is a scavenger of NO and other free radicals, blocked the l-DOPA release induced by 6-MPH4 (200 μM) but this effect did not occur with the addition of the peroxynitrite scavenger uric acid (UA, 300 μM). Sodium nitroprusside (SNP, 100 μM), a NO generator and l-DOPA releaser as previously reported, potentiated the l-DOPA releasing effect of 6-MPH4 (200 μM) which was also blocked by melatonin. In summary 6-MPH4 stimulates l-DOPA release from striatal fragments incubated in vitro by a mechanism which involves NO or other free radicals derived from NO but not peroxynitrite.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Pharmacology - Volume 541, Issues 1–2, 10 July 2006, Pages 33–37
نویسندگان
, , , , , ,