Tissue-specific quantification of bile salts from sexually mature male sea lamprey ( N = 12). 3-keto petromyzonol sulfate (3kPZS), 3-keto allocholic acid (3kACA), petromyzonol sulfate (PZS), allocholic acid (ACA), and petromyzonamine disulfate (PADS) were quantified in liver (L) and gill (G) tissues (ng/g), and plasma (P; ng/ml), using LC-MS/MS. Subjects were a random sub-sample of those used for washings (see Figure 3). Different lower-case letters indicate statistically significant differences between vertical columns within each group (compound). Vertical columns indicate means + 1 SEM (vertical bars), and were compared using ANOVA and post-hoc Tukey’s HSD (α = 0.05).