1,2-sn-Dihexanoylglycerol (HHG) reduced the ATP content of HL-60 cells. This concentration-related (10–100 μM) effect reached a maximum of over 90%, was enantiomerically specific and not accompanied by release of lactate dehydrogenase. Oleoylacetylglycerols (3–100 μM) had no effect on ATP levels while phorbol dibutyrate (PDBu, 0.01–1 μM) decreased ATP content of HL-60 cells by up to 40%. Responses stimulated by HHG became limited as the concentration was increased above 10 μM, this being manifest as either a low maximum response compared to PDBu (superoxide release) or a bell-shaped concentration-effect curve (degranulation). HHG (30–100 μM) inhibited PDBu-stimulated superoxide release, this inhibition being enantiomerically specific. It is probable that the effect of HHG on ATP content impairs cellular reponses mediated through protein kinase C activation.
