A quantitative assessment of F-actin content and distribution in untreated and butyric acid treated murine melanoma B16a tumour cells: a fluorescence image analysis study.

Image analysis of phallacidin, a fluorescent stoichiometric probe to F-actin, permitted the cytoskeletal-associated actin 'F-actin' to be visualized morphologically and to be divided into two groups, diffuse and filamentous. The filamentous actin group was categorized further into four subgroups according to the intensity of the phallacidin probe. F-actin groups and subgroups of untreated cells and cells treated with 1.5 mM butyrate acid were analysed independently. Butyric acid treatment significantly increased total actin, defined as diffuse actin, plus filamentous subgroup actins 1-4. Specifically, butyric acid-treatment increased filamentous subgroup actin 1.