Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Ristocetin: Difference between pages

{{See also|Ristocetin-induced platelet aggregation}}

| Verifiedfields = changed

| verifiedrevid = 464382786

| ImageFile=Ristocetin.png

| ImageSize=200px

| IUPACName=

| OtherNames=

|Section1={{Chembox Identifiers

| InChI = 1/C98H113N7O43/c1-30-50(111)20-39-22-54(30)138-55-21-33(5-12-49(55)110)63(100)88(127)105-67-70(115)35-7-13-52-37(15-35)18-44-62-45-19-38-16-36(8-14-53(38)140-84(45)87(83(44)139-52)148-98-86(78(123)74(119)59(144-98)29-135-94-80(125)75(120)69(114)32(3)137-94)147-97-85(77(122)73(118)58(27-107)143-97)146-95-79(124)71(116)51(112)28-134-95)82(145-60-25-46(99)68(113)31(2)136-60)47-10-9-41(93(132)133-4)42-23-40(108)24-56(141-96-81(126)76(121)72(117)57(26-106)142-96)61(42)43-17-34(6-11-48(43)109)64(89(128)101-47)102-91(130)66(62)104-90(129)65(39)103-92(67)131/h5-8,11-17,20-24,31-32,41,46-47,51,57-60,63-82,85-86,94-98,106-126H,9-10,18-19,25-29,99-100H2,1-4H3,(H,101,128)(H,102,130)(H,103,131)(H,104,129)(H,105,127)/t31-,32+,41-,46+,47?,51-,57+,58-,59-,60+,63?,64?,65?,66?,67+,68-,69+,70+,71-,72+,73-,74-,75-,76-,77+,78+,79+,80-,81-,82+,85+,86-,94-,95+,96+,97-,98+/m0/s1

| CASNo_Ref = {{cascite|changed|??}}

| CASNo=1404-55-3

| PubChem=24846002

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 21106475

| ChEMBL_Ref = {{ebicite|changed|EBI}}

| ChEMBL = 1095986

| SMILES=CC1C(C(CC(O1)OC2C3C(=O)NC(C4=CC(=CC(=C4C5=C(C=CC(=C5)C(C(=O)N3)NC(=O)C6C7=CC(=C(C(=C7)OC8=CC=C2C=C8)OC9C(C(C(C(O9)COC1C(C(C(C(O1)C)O)O)O)O)O)OC1C(C(C(C(O1)CO)O)O)OC1C(C(C(CO1)O)O)O)OC1=CC=C(C=C1)C(C1C(=O)NC(C2=CC(=C(C(=C2)O)C)OC2=C(C=CC(=C2)C(C(=O)N1)N)O)C(=O)N6)O)O)OC1C(C(C(C(O1)CO)O)O)O)O)C(=O)O)N)O

| Formula=C₉₄H₁₀₈N₈O₄₄

| MolarMass=2053.89052

| Appearance=

| Density=

| MeltingPt=

| BoilingPt=

| Solubility=

| MainHazards=

| FlashPt=

| AutoignitionPt =

'''Ristocetin''' is a [[glycopeptide antibiotic]], obtained from ''[[Amycolatopsis]] lurida'', previously used to treat [[staphylococcal infection]]s. It is no longer used clinically because it caused [[thrombocytopenia]] and [[platelet]] [[agglutination (biology)|agglutination]]. It is now used solely to assay those functions ''in vitro'' in the diagnosis of conditions such as [[von Willebrand disease]] (vWD) and [[Bernard–Soulier syndrome]]. Platelet agglutination caused by ristocetin can occur only in the presence of [[von Willebrand factor]] multimers, so if ristocetin is added to blood lacking the factor (or its receptor—see below), the platelets will not clump.

Through an unknown mechanism, the antibiotic ristocetin causes von Willebrand factor to bind the platelet receptor glycoprotein Ib (GpIb), so when ristocetin is added to normal blood, it causes agglutination.

In some types of vWD (types 2B and platelet-type), even very small amounts of ristocetin cause platelet aggregation when the patient's platelet-rich [[Blood plasma|plasma]] is used.<ref>{{cite book |last=McPherson |first=Richard A. |author2=Matthew R. Pincus |title=Henry's Clinical Diagnosis and Management by Laboratory Methods |publisher=W. B. Saunders|location=Philadelphia |year=2006 |pages=760–2 |isbn=978-1-4160-0287-1}}</ref> This paradox is explained by these types having [[mutation|gain-of-function mutations]] which cause the vWD high molecular-weight multimers to bind more tightly to their receptors on platelets (the alpha chains of [[glycoprotein Ib (GPIb)]] receptors). In the case of type 2B vWD, the gain-of-function mutation involves von Willebrand's factor (VWF gene), and in platelet-type vWD, the receptor is the object of the mutation (GPIb). This increased binding causes vWD because the high-molecular weight multimers are removed from circulation in plasma since they remain attached to the patient's platelets. Thus, if the patient's platelet-poor plasma is used, the ristocetin cofactor assay will not agglutinate standardized platelets (i.e., pooled platelets from normal donors that are fixed in formalin), similar to the other types of vWD.

In all forms of the ristocetin assay, the platelets are fixed in [[formalin]] prior to the assay to prevent von Willebrand's factor stored in platelet granules from being released and participating in platelet aggregation. Thus, the ristocetin cofactor activity depends only upon high-molecular multimers of the factor present in circulating plasma.

{{Table of platelet aggregation disorders and agonists}}

==References==

{{reflist}}

{{Cell wall disruptive antibiotics}}

[[Category:Antibiotics]]

[[Category:Glycopeptide antibiotics]]

[[Category:Chemical pathology]]