Phosphoinositol metabolism

This pathway is ubiquitous in many cell types and has also been imphcated in the mechanism of phar-macomechanical coupling in ASM. Phosphoinositol metabolism and rapid rises in the cellular levels of IP3 follow stimulation by a variety of a nists - carbachol, histamine, neurokinins and leukotrienes in canine, guinea-pig and bovine ASM (Hashimoto et al., 1985 Grandordy et al., 1986, 1988 Duncan et /, 1987 Kardasz a al., 1988 Chilvers et al., 1989, 1991). This rise in IP3 precedes contraction (Duncan et al., 1987). 

Chilvers, E. and Nahorski, S. (1990). Phosphoinositol metabolism in airway smooth muscle. Am. Rev. Respir. Dis. 141, S137-S140. 

DAG and Ins( 1,4,5)P3 are thought to possess regulatory functions in the process of insulin release. Further products of inositol phosphate metabolism will not be discussed here. Phosphoinositol turnover is, however, neither necessary nor sufficient to initiate insulin release (Axen et al., 1983 Layschock, 1983), but it has been found to augment glucose-induced secretion of insulin. 

S., and Muller, G. Structure-activity relationship of synthetic phosphoinositol-glycans mimicking metabolic insulin action. Biochemistry, 1998, 37, 13421-13436. 

G. Muller, S. Wied, A. Crecelius, A. Kessler, and J. Eckel, Phosphoinositol -glycan-peptides from yeast potently induce metabolic insulin actions in isolated rat adipocytes, cardiomyocytes and diaphragm, Endocrinology, 1997, 138, 3459-3475. 

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