Skip to main content
PMC home page
Biochemical Journal logoLink to Biochemical Journal
. 1988 Aug 15;254(1):147–153. doi: 10.1042/bj2540147

Alcohol-induced stimulation of phospholipase C in human platelets requires G-protein activation.

R Rubin 1, J B Hoek 1
PMCID: PMC1135050  PMID: 3140795

Abstract

In previous studies we have demonstrated that ethanol activates hormone-sensitive phospholipase C in intact human platelets, resulting in the mobilization of intracellular Ca2+ and platelet shape change. The present study aims to localize further this effect of ethanol by examining its interaction with the regulation of phospholipase C in a permeabilized cell system. In platelets permeabilized with a minimal concentration (18 micrograms/ml) of saponin, ethanol by itself did not activate phospholipase C. However, ethanol potentiated the activation of phospholipase C in response to the non-hydrolysable GTP analogue GTP[S] (guanosine 5'-[gamma-thio]triphosphate), an effect similar to that observed with thrombin. Ethanol also potentiated the response to fluoride, which acts directly on G-proteins. Other short-chain alcohols also stimulated phospholipase C in a synergistic manner with GTP[S]. The ability of specific alcohols to stimulate phospholipase C was directly related to their respective lipid-solubilities, as determined by their partition coefficients. Moreover, the potencies of each alcohol correlated with their ability to elicit Ca2+ mobilization and shape change in intact platelets. These effects of ethanol were eliminated by a disruption of receptor-phospholipase C coupling induced by the addition of higher concentrations of saponin. These data indicate that the activation of phospholipase C by ethanol may occur by affecting protein-protein interactions in the signal-transduction complex involving GTP-binding regulatory proteins.

Full text

PDF
149

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Authi K. S., Evenden B. J., Crawford N. Metabolic and functional consequences of introducing inositol 1,4,5-trisphosphate into saponin-permeabilized human platelets. Biochem J. 1986 Feb 1;233(3):707–718. doi: 10.1042/bj2330707. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Baldassare J. J., Fisher G. J. Regulation of membrane-associated and cytosolic phospholipase C activities in human platelets by guanosine triphosphate. J Biol Chem. 1986 Sep 15;261(26):11942–11944. [PubMed] [Google Scholar]
  3. Brass L. F., Joseph S. K. A role for inositol triphosphate in intracellular Ca2+ mobilization and granule secretion in platelets. J Biol Chem. 1985 Dec 5;260(28):15172–15179. [PubMed] [Google Scholar]
  4. Brass L. F., Laposata M., Banga H. S., Rittenhouse S. E. Regulation of the phosphoinositide hydrolysis pathway in thrombin-stimulated platelets by a pertussis toxin-sensitive guanine nucleotide-binding protein. Evaluation of its contribution to platelet activation and comparisons with the adenylate cyclase inhibitory protein, Gi. J Biol Chem. 1986 Dec 25;261(36):16838–16847. [PubMed] [Google Scholar]
  5. Cooper R. H., Coll K. E., Williamson J. R. Differential effects of phorbol ester on phenylephrine and vasopressin-induced Ca2+ mobilization in isolated hepatocytes. J Biol Chem. 1985 Mar 25;260(6):3281–3288. [PubMed] [Google Scholar]
  6. Franks N. P., Lieb W. R. Molecular mechanisms of general anaesthesia. Nature. 1982 Dec 9;300(5892):487–493. doi: 10.1038/300487a0. [DOI] [PubMed] [Google Scholar]
  7. Grynkiewicz G., Poenie M., Tsien R. Y. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem. 1985 Mar 25;260(6):3440–3450. [PubMed] [Google Scholar]
  8. Hoek J. B., Rubin R., Thomas A. P. Ethanol-induced phospholipase C activation is inhibited by phorbol esters in isolated hepatocytes. Biochem J. 1988 May 1;251(3):865–871. doi: 10.1042/bj2510865. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Hoek J. B., Thomas A. P., Rubin R., Rubin E. Ethanol-induced mobilization of calcium by activation of phosphoinositide-specific phospholipase C in intact hepatocytes. J Biol Chem. 1987 Jan 15;262(2):682–691. [PubMed] [Google Scholar]
  10. Jolles J., Wirtz K. W., Schotman P., Gispen W. H. Pituitary hormones influence polyphosphoinositide metabolism in rat brain. FEBS Lett. 1979 Sep 1;105(1):110–114. doi: 10.1016/0014-5793(79)80897-2. [DOI] [PubMed] [Google Scholar]
  11. Lapetina E. G. Effect of pertussis toxin on the phosphodiesteratic cleavage of the polyphosphoinositides by guanosine 5'-O-thiotriphosphate and thrombin in permeabilized human platelets. Biochim Biophys Acta. 1986 Nov 19;884(2):219–224. doi: 10.1016/0304-4165(86)90166-2. [DOI] [PubMed] [Google Scholar]
  12. Lapetina E. G., Silió J., Ruggiero M. Thrombin induces serotonin secretion and aggregation independently of inositol phospholipids hydrolysis and protein phosphorylation in human platelets permeabilized with saponin. J Biol Chem. 1985 Jun 10;260(11):7078–7083. [PubMed] [Google Scholar]
  13. Luthin G. R., Tabakoff B. Activation of adenylate cyclase by alcohols requires the nucleotide-binding protein. J Pharmacol Exp Ther. 1984 Mar;228(3):579–587. [PubMed] [Google Scholar]
  14. Lynch C. J., Charest R., Bocckino S. B., Exton J. H., Blackmore P. F. Inhibition of hepatic alpha 1-adrenergic effects and binding by phorbol myristate acetate. J Biol Chem. 1985 Mar 10;260(5):2844–2851. [PubMed] [Google Scholar]
  15. Lyon R. C., McComb J. A., Schreurs J., Goldstein D. B. A relationship between alcohol intoxication and the disordering of brain membranes by a series of short-chain alcohols. J Pharmacol Exp Ther. 1981 Sep;218(3):669–675. [PubMed] [Google Scholar]
  16. McCreery M. J., Hunt W. A. Physico-chemical correlates of alcohol intoxication. Neuropharmacology. 1978 Jul;17(7):451–461. doi: 10.1016/0028-3908(78)90050-3. [DOI] [PubMed] [Google Scholar]
  17. McGowan E. B., Detwiler T. C. Modified platelet responses to thrombin. Evidence for two types of receptors or coupling mechanisms. J Biol Chem. 1986 Jan 15;261(2):739–746. [PubMed] [Google Scholar]
  18. Miller K. W. The nature of the site of general anesthesia. Int Rev Neurobiol. 1985;27:1–61. doi: 10.1016/s0074-7742(08)60555-3. [DOI] [PubMed] [Google Scholar]
  19. Rock C. O., Jackowski S. Thrombin- and nucleotide-activated phosphatidylinositol 4,5-bisphosphate phospholipase C in human platelet membranes. J Biol Chem. 1987 Apr 25;262(12):5492–5498. [PubMed] [Google Scholar]
  20. Rubin R., Ponnappa B. C., Thomas A. P., Hoek J. B. Ethanol stimulates shape change in human platelets by activation of phosphoinositide-specific phospholipase C. Arch Biochem Biophys. 1988 Jan;260(1):480–492. doi: 10.1016/0003-9861(88)90472-9. [DOI] [PubMed] [Google Scholar]
  21. Rubin R., Thomas A. P., Hoek J. B. Ethanol does not stimulate guanine nucleotide-induced activation of phospholipase C in permeabilized hepatocytes. Arch Biochem Biophys. 1987 Jul;256(1):29–38. doi: 10.1016/0003-9861(87)90422-x. [DOI] [PubMed] [Google Scholar]
  22. Siess W., Lapetina E. G. Neomycin inhibits inositol phosphate formation in human platelets stimulated by thrombin but not other agonists. FEBS Lett. 1986 Oct 20;207(1):53–57. doi: 10.1016/0014-5793(86)80011-4. [DOI] [PubMed] [Google Scholar]
  23. Suzdak P. D., Schwartz R. D., Skolnick P., Paul S. M. Ethanol stimulates gamma-aminobutyric acid receptor-mediated chloride transport in rat brain synaptoneurosomes. Proc Natl Acad Sci U S A. 1986 Jun;83(11):4071–4075. doi: 10.1073/pnas.83.11.4071. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Taraschi T. F., Rubin E. Effects of ethanol on the chemical and structural properties of biologic membranes. Lab Invest. 1985 Feb;52(2):120–131. [PubMed] [Google Scholar]
  25. Thomas A. P., Marks J. S., Coll K. E., Williamson J. R. Quantitation and early kinetics of inositol lipid changes induced by vasopressin in isolated and cultured hepatocytes. J Biol Chem. 1983 May 10;258(9):5716–5725. [PubMed] [Google Scholar]
  26. Tsien R. Y. A non-disruptive technique for loading calcium buffers and indicators into cells. Nature. 1981 Apr 9;290(5806):527–528. doi: 10.1038/290527a0. [DOI] [PubMed] [Google Scholar]
  27. Zucker M. B., Nachmias V. T. Platelet activation. Arteriosclerosis. 1985 Jan-Feb;5(1):2–18. doi: 10.1161/01.atv.5.1.2. [DOI] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES