Originariamente Scritto da MrAffondo
Finita la gluta...prendo argi?
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Arginine-140 and isoleucine-141 determine the 17ß-estradiol-binding specificity of the sex-steroid-binding protein (SBP, or SHBG) of human plasma
<nobr>Philip H. Petra<sup>1</sup></nobr>, <nobr>Elinor T. Adman<sup>2</sup></nobr>, <nobr>William R. Orr<sup>1</sup></nobr>, <nobr>Katherine T. Woodcock<sup>1</sup></nobr>, <nobr>Christine Groff<sup>1</sup></nobr> and <nobr>Li-Ming Sui<sup>3</sup></nobr> <sup>1</sup> Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
<sup>2</sup> Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA
Reprint requests to: Philip H. Petra, Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; e-mail: hue@u.washington.edu<script type="text/javascript"><!-- var u = "hue", d = "u.washington.edu"; document.getElementById("em0").innerHTML = "<a href="mailto:" + u + "@" + d + "">" + u + "@" + d + "<\/a>"//--></script>; fax: (206) 543-6092.
<!-- ABS --> Arginine-140 and isoleucine-141 were identified as key determinants<sup> </sup>of 17ß-estradiol (E<sub>2</sub>) binding affinity of the sex-steroid-binding<sup> </sup>protein (SBP, or SHBG) of human plasma. Amino acid residues<sup> </sup>that differ between human and rabbit SBP sequences were replaced<sup> </sup>in the human protein and the products tested for lowered E<sub>2</sub>binding<sup> </sup>activity as are seen in the rabbit protein. Only mutants containing<sup> </sup>either R140K or I141L replacements display an E<sub>2</sub> equilibrium<sup> </sup>dissociation constant (Kd) higher than the wild type, reaching<sup> </sup>a value of 30 nM when both were present. The 5-dihydrotestosterone<sup> </sup>(DHT) equilibrium dissociation constant of these mutants was<sup> </sup>unaffected. The quadruple mutant M107I/I138V/R140K/I141L yielded<sup> </sup>an E<sub>2</sub> Kd of 65 nM, significantly closer to the 80 nM rabbit<sup> </sup>SBP E<sub>2</sub> Kd value. Although mutants containing the M107I and I138V<sup> </sup>replacements in the absence of R140K and I141L had normal E<sub>2</sub><sup> </sup>Kds, the presence of the M107I replacement in the quadruple<sup> </sup>mutant was necessary to obtain an accurate E<sub>2</sub> Kd value by competitive<sup> </sup>Scatchard analysis. Molecular modeling using coordinates for<sup> </sup>the recently determined N-terminal domain of human SBP revealed<sup> </sup>a significant shift of the F56 phenyl ring away from ring A<sup> </sup>of E<sub>2</sub> in mutant models containing the R140K and I141L replacements.<sup> </sup>We conclude that R140 and I141 are required for sustaining the<sup> </sup>right proximity of the phenyl ring of F56 to ring A of 17ß-estradiol,<sup> </sup>thus optimizing the E<sub>2</sub>-binding affinity of human SBP.
Questo è quello di più serio che ho trovato a riguardo...Ma da qui a dire che l'assunzione orale di arginina aumenti il testosterone mi pare ce ne passi...
Senza alcuna polemica ovviamentesigpic
hana wa sakuragi, hito wa bushi.
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Originariamente Scritto da MrAffondoArginine-140 and isoleucine-141 determine the 17ß-estradiol-binding specificity of the sex-steroid-binding protein (SBP, or SHBG) of human plasma
<nobr>Philip H. Petra<sup>1</sup></nobr>, <nobr>Elinor T. Adman<sup>2</sup></nobr>, <nobr>William R. Orr<sup>1</sup></nobr>, <nobr>Katherine T. Woodcock<sup>1</sup></nobr>, <nobr>Christine Groff<sup>1</sup></nobr> and <nobr>Li-Ming Sui<sup>3</sup></nobr> <sup>1</sup> Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
<sup>2</sup> Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA
Reprint requests to: Philip H. Petra, Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; e-mail: hue@u.washington.edu<script type="text/javascript"><!-- var u = "hue", d = "u.washington.edu"; document.getElementById("em0").innerHTML = "<a href="mailto:" + u + "@" + d + "">" + u + "@" + d + "<\/a>"//--></script>; fax: (206) 543-6092.
<!-- ABS --> Arginine-140 and isoleucine-141 were identified as key determinants<sup> </sup>of 17ß-estradiol (E<sub>2</sub>) binding affinity of the sex-steroid-binding<sup> </sup>protein (SBP, or SHBG) of human plasma. Amino acid residues<sup> </sup>that differ between human and rabbit SBP sequences were replaced<sup> </sup>in the human protein and the products tested for lowered E<sub>2</sub>binding<sup> </sup>activity as are seen in the rabbit protein. Only mutants containing<sup> </sup>either R140K or I141L replacements display an E<sub>2</sub> equilibrium<sup> </sup>dissociation constant (Kd) higher than the wild type, reaching<sup> </sup>a value of 30 nM when both were present. The 5-dihydrotestosterone<sup> </sup>(DHT) equilibrium dissociation constant of these mutants was<sup> </sup>unaffected. The quadruple mutant M107I/I138V/R140K/I141L yielded<sup> </sup>an E<sub>2</sub> Kd of 65 nM, significantly closer to the 80 nM rabbit<sup> </sup>SBP E<sub>2</sub> Kd value. Although mutants containing the M107I and I138V<sup> </sup>replacements in the absence of R140K and I141L had normal E<sub>2</sub><sup> </sup>Kds, the presence of the M107I replacement in the quadruple<sup> </sup>mutant was necessary to obtain an accurate E<sub>2</sub> Kd value by competitive<sup> </sup>Scatchard analysis. Molecular modeling using coordinates for<sup> </sup>the recently determined N-terminal domain of human SBP revealed<sup> </sup>a significant shift of the F56 phenyl ring away from ring A<sup> </sup>of E<sub>2</sub> in mutant models containing the R140K and I141L replacements.<sup> </sup>We conclude that R140 and I141 are required for sustaining the<sup> </sup>right proximity of the phenyl ring of F56 to ring A of 17ß-estradiol,<sup> </sup>thus optimizing the E<sub>2</sub>-binding affinity of human SBP.
Questo è quello di più serio che ho trovato a riguardo...Ma da qui a dire che l'assunzione orale di arginina aumenti il testosterone mi pare ce ne passi...
Senza alcuna polemica ovviamente
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Originariamente Scritto da Drugo84no, è vero del NO (infatti la usai anche come veicolante con glicerina) ma ci sono anche prodotti migliori x questo ma lavora diminuendo l'azioen dell'SHBG ... e ti assicuro che si sente
l'HO PROVATA A PRENDERE 8 GR OGGI DOPO PRANZO E MI SONO SPARATO 2 ORE E MEZZO DI SONNO MA UN SONNO SECONDO ME DIVERSO DAL SOLITO PISOLINO POST PRANZO!
ma se diminuisce l'azione delle shbg non sarebbe meglio assumerla anche alla mattina intorno alle 7 8 di mattina?Manowar: king of Metal
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Originariamente Scritto da Drugo84ma guarda caso conferma in parte ciò che dico sull'affinità ad aumetnare il testo libero (che ce ne frega se abbiamo 1g di testo in carpo quando ne basta 2mg liberi? )sigpic
hana wa sakuragi, hito wa bushi.
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Originariamente Scritto da SancezbE ALLORA MEGLIO ALLA MATTINA!
l'HO PROVATA A PRENDERE 8 GR OGGI DOPO PRANZO E MI SONO SPARATO 2 ORE E MEZZO DI SONNO MA UN SONNO SECONDO ME DIVERSO DAL SOLITO PISOLINO POST PRANZO!
ma se diminuisce l'azione delle shbg non sarebbe meglio assumerla anche alla mattina intorno alle 7 8 di mattina?
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Oh raga ho risolto la question ho preso di nuovo la glutammina...ci sono affezionato è un pò come una seconda mamma
Ah parte le balle piuttosto che tentare sentieri oscuri ed inesplorati preferisco passare su una bella autostrada segnalata fatta più volte
Sono metaforico stasera ...ciao e grazie dei consigli
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