Swiss-mouse 3T3 cells permeabilized with saponin were used to study the specificity of the inositol trisphosphate-induced release of 45Ca2+ from their intracellular stores. Inositol 1,4,5-trisphosphate was the most potent compound studied (dose giving half-maximal effect 0.3 microM). 45Ca2+ was also released by inositol 2,4,5-trisphosphate, glycerophosphoinositol 4,5-bisphosphate and inositol 4...

A growing body of research is currently focused on the role of inositol isomers and in particular myo-inositol (MYO-INS) and D-chiroinositol (DCI) in the treatment of insulin resistance states. Both isomers have been shown to exert insulin-mimetic action and to lower postprandial glucose. Further, insulin resistance-related diseases were associated to derangements in inositol metabolism. Thus, ...

In this study, the effects of inositol addition on maltase activity and expression of MAL1+ gene encoding maltase in Schizosaccharomyces pombe were investigated. The maximum specific maltase activity was observed, when the concentration of inositol reached 6.0 microg/ml in the synthetic medium containing 2.0% glucose. At 1.0 microg/ml inositol concentration, the maltase activity continuously de...

Incubation of mature sweet corn kernels of Zea mays in dilute solutions of (14)C-labeled indole-3-acetic acid leads to the formation of (14)C-labeled esters of myo-inositol, glucose, and glucans. Utilizing this knowledge it was found that an enzyme preparation from immature sweet corn kernels of Zea mays catalyzed the CoA- and ATP-dependent esterification of indole-3-acetic acid to myo-inositol...

Metabolism of inositol phospholipids and phosphatidylcholine was investigated in tracheobronchial epithelial cells exposed to mitogenic concentrations of crocidolite asbestos. Alterations in levels of diacylglycerol, the endogenous activator of protein kinase C, and inositol polyphosphates, presumed mobilizers of intracellular calcium, were examined. Cultures labeled with [3H]glycerol and expos...

The enzymatic synthesis of inositol monophosphatide has been described in reports by Agranoff et al. (l), Thompson et al. (2), and Paulus and Kennedy (3, 4). An enzymatic reaction in which free inositol is incorporated into inositol phosphatide, stimulated by the addition of any of a number of cytidine nucleotides, including cytidine 5’-monophosphate and cytidine diphosphate choline, was fnst o...

The main phototransduction cascade in invertebrate visual cells involves the turnover of phosphatidylinositol, an important biochemical mechanism common to many signal-transduction systems. Light-activated rhodopsin stimulates guanine nucleotide exchange on the Gq class of G-protein, which activates phospholipase C to hydrolyze phosphatidylinositol 4,5-bisphosphate to inositol-1,4,5-trisphospha...

Of two major forms (myo- and chiro-inositol) of inositols, only chiro-inositol enhances the activity of proteins involved in intracellular glucose metabolism. This study aims to determine the urinary myo-/chiro-inositol ratio in type 1 and type 2 diabetes patients and compare its ratio with the normal control group. The 24-hour urinary myo- and chiro-inositols in 71 Korean diabetes patients and...

The addition of 5-hydroxytryptamine to the isolated blowfly salivary gland stimulates fluid secretion, transepithelial calcium transport and the breakdown of 32P- or 3H-labelled phosphatidylinositol The breakdown of [32P]phosphatidylcholine and [32P]-phosphatidylethanolamine was not stimulated by 5-hydroxytryptamine. In salivary glands incubated with myo-[2-3H]inositol for 1--3 h, more than 95%...