Biomarkers of Adverse Response to Mercury: Histopathology versus Thioredoxin Reductase Activity

Table 1

Values of the organ damage index^* (ODI) calculated for the liver and kidney of zeabra-seabreams exposed to the different treatments. No lesions were observed in control fishes. MeHg: exposure to Methylmercury; HgII: exposure to Hg²⁺; MeHgSe: coexposure to MeHg and Se; HgSe: coexposure to Hg²⁺ and Se; MeHgRSe: exposure to MeHg followed by exposure to Se during depuration; HgRSe: exposure to Hg²⁺ followed by exposure to Se during depuration; Se: exposure to selenium.

	Organ lesion (OL)	Pi	MeHg		HgII		MeHgSe		HgSe		MeHgRSe	HgRSe	Se
			d28	d42	d28	d42	d28	d42	d28	d42	d42	d42	d28	d42
			𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL	𝑁OL
Liver	Architectural pattern lost	1	4	3	4	4	3	2	4	0	3	3	2	0
	Vacuolar degeneration	1	3	1	4	1	2	0	1	2	3	3	2	0
	Hydropic degeneration	1	4	2	3	1	1	2	1	1	0	3	0	0
	Hypertrophy of hepatocytes	2	2	3	1	4	4	0	4	1	0	0	0	0
	Extensive focal necrosis	3	0	3	2	4	0	2	1	3	0	2	0	0
	Focal necrosis	2	3	0	0	0	1	2	2	0	3	1	0	0
	Parenchymal congestion	1	0	1	2	0	1	0	3	0	0	0	0	0
	Pigment deposition	1	0	0	2	0	0	0	0	0	0	0	0	0
	ODI		21	22	23	26	17	14	24	14	12	17	4	0
Kidney	Vacuolar degeneration	1	1	0	1	2	1	1	0	1	1	2	0	0
	Hydropic degeneration	1	3	2	1	0	1	3	0	3	0	2	0	0
	Pigment deposition	1	3	1	1	1	0	2	0	1	1	0	0	0
	Parenchymal necrosis	3	0	0	0	3	0	0	1	0	0	0	0	0
	ODI		7	3	3	12	2	6	3	5	2	4	0	0

Pi: Pathological index of each lesion according to their importance to organ function [38].
𝑁_OL: number of fishes displaying one type of organ lesion (OL).
^*ODI: sum of lesions observed for each organ taking into account their relative severity and the number of fishes (𝑁_OL).