Alteration of cytoplasmic Ca2+ in resting and stimulated human neutrophils by short-chain carboxylic acids at neutral pH

The results reported here indicate that the short-chain carboxylic acids acetate and propionate stimulate cytoplasmic calcium mobilization in human polymorphonuclear leukocytes, while butyrate and lactate do not. Together with the results of previous work, this indicates that there are at least three classes of short-chain carboxylic acids: those which can alter only cytoplasmic pH (e.g., lactic acid), those which can alter cytoplasmic pH and actin (e.g., butyric acid), and those which can alter cytoplasmic pH, actin, and calcium (e.g., acetate and propionate).