Dimorphic Stress Hormones Figure 5. Triglyceride levels are altered in genotypes differing in corazonin neuronal function. A. Total triglycerides were measured in animals with different corazonin neuronal function during starvation conditions. Three replicate vials of thirty animals per genotype were placed in vials containing 2% agar, collected at the designated times and triglycerides were measured. Values were normalized to weight and compared to standards. Note that prior to starvation, corazonin neuronal ablation results in higher triglyceride content. Additionally, the slopes of the regression lines are not different in males, whereas in females, the slopes significantly differ as determined by a Homogeneity of Slopes test. B. Triglyceride measurements from parental and experimental genotypes under normal rearing conditions. Data are means +/2 SEM from three replicate experiments and asterisks indicate statistical significance (p,0.05) (ANOVA). doi:10.1371/journal.pone.0009141.g005 (Figure 6). Dopamine levels were significantly higher in hemolymph derived from both males and females with ablated corazonin neurons. However, for the other genotypes there was also a strong dependence upon sex (P,0.0001, F = 33.44 Two-Way ANOVA). For males with silenced corazonin neurons, dopamine levels were also higher than parental genotypes. However, in females both activated and silenced corazonin cells have comparable dopamine levels as compared to parental genotypes. Since manipulations predicted to alter excitability of these neurons don’t result in large or consistent changes in dopamine levels (see legend to Fig. 6), these manipulations may not fully block corazonin release. Notably, these effects were seen only in hemolymph samples, as brains derived from these different genotypes had dopamine levels that were not different than w1118 (data not shown). While dopamine levels change as a function of development, the most significant changes in dopamine levels occur coincident with eclosion and cuticular tanning, which PLoS ONE | www.plosone.org 9 February 2010 | Volume 5 | Issue 2 | e9141