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|Section2= |Section3= }} ''muco''-Inositol is a critically important chemical in the gustatory (taste) modality of the mammalian nervous system. The generic form is coupled to a phospholipid of the outer lemma of the sensory neurons associated with the sodium ion sensitive channel (previously known as the “salty” channel) of gustation. ''Muco''-inositol is one of nine stereo-isomers of inositol. It is the only stereo-isomer that participates in the gustatory (taste) modality. ''Muco''-inositol is typically phosphorylated (becoming ''muco''-inositol phosphate) in the process of being attached to a lipid of the outer lemma of the sensory neurons of taste. The final chemical is phosphatidyl ''muco''-inositol (PtdIns). PtdIns occurs in a specialized area of the cilia of the sensory neurons where it exists in a liquid crystalline form. In this form, it is the sensory receptor of the sensory neuron forming the initial element of the sodium ion sensitive channel of gustation. Phosphatidyl inositol prepared in the laboratory without regard to the isomer involved is abbreviated as PI. Phosphatidyl inositol phosphate prepared without regard to the isomer involved is abbreviated as PIP. Generic ''muco''-inositol alone can form a dimer with the ''muco''-inositol moiety of the sensory receptor. Although it contains no salt, or sodium ion, ''muco''-inositol is perceived as very “salty” in this situation. It contains a natraphore within its structure. Generic ''muco''-inositol can also couple with the gluco-receptor of the "sweet" sensory neurons and be perceived as sweet by mammals, even though it is not a saccharide. While classed as a sugar-alcohol for historical reasons, ''muco''-inositol is more properly described as a sweet-alcohol due its perception by the mammal as sweet. It contains two distinct glucophores, as well as two distinct natrophores, within its aromatic structure. Aliphatic alcohols do not contain any gustaphores in their pure state and are considered tasteless. However, many impurities (more than one part per million) have been present in the aliphatic alcohols used in laboratory experiments, resulting in their having been assigned a perceptual "taste." ==Nomenclature== Nomenclature is extremely important as it relates to ''muco''-inositol. The utilization of this material in the neural system of the biological entity is totally dependent on the precise stereo-chemistry of this stereo-isomer. Unfortunately, the nomenclature has gone through a series of significant changes during the last thirty years. Only the literature subsequent to 1988 can be depended upon in this regard.〔NC-IUB (Moss, G. ed.) (1988) Numbering of atoms in myo-inositol http://www.chem.qmul.ac.uk/iupac/cyclitol/myo.html〕 Muco-inositol (CAS 488-55-1) is a particular isomer of (and frequently confused with) the generic cyclohexane 1,2,3,4,5,6 hexol (CAS 87-89-8). This confusion should be avoided. The correct "chair" representation of ''muco''-inositol is shown here. The numbering reflects the recommended 1988 numbering based on the fact that the isomer is typically phosphorylated at the hydroxyl group associated with the #1 carbon when used as the hydrated sodium receptor. It is quite difficult to represent the critical stereo-graphic features of ''muco''-inositol without employing the three-dimensional representation provided by the Jmol 3D images in the Chembox at upper right. The reason is that the distances between pairs of specific oxygen atoms are critically important to its operation as the active portion of the sodium channel sensory receptor. The values calculated using the Jmol script on this page will be used in this article in place of the preferred but unavailable measured values of these distances. There are many inaccurate Jmol representations of ''muco''-inositol present on the internet. Please use caution and verify the accuracy of any other Jmol script used. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Muco-Inositol」の詳細全文を読む スポンサード リンク
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