| In vitro: | 
				| Biochimica Et Biophysica Acta General Subjects, 1981, 678(2):238-244.  |  | Activation of superoxide production and differential exocytosis in polymorphonuclear leukocytes by cytochalasins A, B, C, D and E: Effects of various ions.[Reference: WebLink] |  All of the common cytochalasins activate superoxide anion release and exocytosis of beta-N-acetylglucosaminidase and lysozyme from guinea-pig polymorphonuclear leukocytes (neutrophils) incubated in a buffered sucrose medium. 
 METHODS AND RESULTS: 
Half-maximal activation of both processes is produced by approx. 0.2 microM cytochalasin A, cytochalasin C greater than 2 microM cytochalasin B greater than or equal to 4-5 microM cytochalasin D, cytochalasin E. While maximal rates of O2- release and extents of exocytosis require extracellular calcium (1-2 mM), replacing sucrose with monovalent cation chlorides is inhibitory to neutrophil activation by cytochalasins. Na , K  or choline inhibit either cytochalasin B- or E-stimulated O2- production with IC50 values of 5-10 mM and inhibition occurs whether Cl-, NO3- or SCN- is the anion added with Na  or K . Release of beta-N-acetylglucosaminidase in control or cytochalasin B-stimulated cells is inhibited by NaCl(IC50 approximately 10 mM), while cytochalasin E-stimulated exocytosis is reduced less and K  or choline chloride are ineffective in inhibiting either cytochalasin B- or E-stimulated exocytosis. Release of beta-glucuronidase, myeloperoxidase or acid phosphatase from neutrophils incubated in buffered sucrose is not stimulated by cytochalasin B. Stimulation of either O2- or beta-N-acetylglucosaminidase release by low concentrations of cytochalasin A is followed by inhibition of each at higher concentrations. 
 CONCLUSIONS: 
It appears that all cytochalasins can activate both NAD(P)H oxidase and selective degranulation of neutrophils incubated in salt-restricted media and that differential inhibition of these two processes by monovalent cations and/or anions is produced at some step(s) subsequent to cytochalasin interaction with the cell. |  
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