Academic Journal
3‐[(3‐Cholamidopropyl)dimethylammonio]‐1‐Propane Sulfonate‐Solubilized Binding Sites for 2‐[ 125 I]Iodomelatonin in Chick Brain Retain Sensitivity to Guanine Nucleotides
| العنوان: | 3‐[(3‐Cholamidopropyl)dimethylammonio]‐1‐Propane Sulfonate‐Solubilized Binding Sites for 2‐[ 125 I]Iodomelatonin in Chick Brain Retain Sensitivity to Guanine Nucleotides |
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| المؤلفون: | Ying, Shui‐Wang, Niles, Lennard P. |
| المصدر: | Journal of Neurochemistry ; volume 56, issue 2, page 580-586 ; ISSN 0022-3042 1471-4159 |
| بيانات النشر: | Wiley |
| سنة النشر: | 1991 |
| المجموعة: | Wiley Online Library (Open Access Articles via Crossref) |
| الوصف: | Binding of 2‐[ 125 I]iodomelatonin to 3‐[(3‐chol‐amidopropyl)dimethylammonio]‐1‐propane sulfonate (CHAPS)‐solubilized sites from chick forebrain was rapid, reversible, saturable, of high affinity, and of pharmacological selectivity. Scatchard analyses showed that 2‐( 125 I]iodomelatonin binds to a single site with equilibrium dissociation constant ( K D ) values of 328 ± 22 (n = 4) and 302 ± 26 p M (n = 3) and a maximal number of binding sites ( B max ) of 36.2 ± 2.0 and 49.5 ± 6.6 fmol/mg of protein in solubilized and membrane fractions, respectively. The K D values obtained from the ratio of kinetic constants ( k 2 / k 1 ) in solubilized and membrane preparations were 228 and 216 p M , respectively. Inhibition studies indicated the following order of pharmacological affinities for both membrane and solubilized sites: 2‐iodomelatonin > melatonin > 6‐chloromelatonin ± prazosin > N ‐acetylserotonin ± serotonin > metergoline > ketanserin > propranolol > phentolamine > cyproheptadine. Guanyl nucleotides inhibited binding of 2‐[ 125 I]iodomelatonin to solubilized and membrane fractions, by converting binding sites from a high‐affinity to a lowaffinity state. These findings show that solubilized binding sites for melatonin exhibit the specific binding and pharmacological characteristics present in membrane‐bound sites. Moreover, the retention of sensitivity to guanine nucleotides in fractions solubilized with CHAPS suggests that this solubilization procedure is suitable for further studies aimed at the isolation, purification, and molecular characterization of active melatonin binding sites. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1111/j.1471-4159.1991.tb08189.x |
| الاتاحة: | http://dx.doi.org/10.1111/j.1471-4159.1991.tb08189.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1471-4159.1991.tb08189.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1471-4159.1991.tb08189.x |
| Rights: | http://onlinelibrary.wiley.com/termsAndConditions#vor |
| رقم الانضمام: | edsbas.86B281FD |
| قاعدة البيانات: | BASE |
| DOI: | 10.1111/j.1471-4159.1991.tb08189.x |
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