Fig. 2. The NOS inhibitor L-aminoguanidine (LAG) inhibits both lipopolysaccharide (LPS) and heat stress-induced NO production in A. pallida. (A) Gray-scale rendering of confocal images of DAF-FM-loaded tentacles of aposymbiotic anemones incubated for 5 h in 1 µg ml^-1 LPS alone (left) or in LPS with 10 mmol l^-1 LAG (right). (B) Quantification of DAF-FM fluorescence as a function of heat stress alone and in the presence of 10 mmol l^-1 LAG (N=3 anemones per treatment; bars represent means + s.d.). Heat-stressed anemones showed a significantly greater (^*) DAF-FM fluorescence than control or heat-stressed anemones incubated in LAG (ANOVA, P=0.006; Tukey HSD, P=0.021).