Effect of brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) (10-6 M) on the apoptotic activity of Pseudomonas fluorescens MF37. The apoptotic effect of the bacterium was determined by measurement of the accumulation in the medium of NO2- resulting from the activation of inducible NO synthase activity in glial cells. Values are expressed as the mean concentration of NO2- produced by glial cells following exposure (24 h) to untreated (n = 28) or treated (n = 24 for BNP, and n = 15 for CNP) bacteria. Data are means of four independent experiments. *** : Significantly different (P < 0.001). NS: Not significantly different.