PDF-OUTPUT Fish Physiol Biochem (2006) DOI 10.1007/s10695-006-0041-2 Effects of malathion and cadmium on acetylcholinesterase activity and metallothionein levels in the fish Seriola dumerilli J. Jebali M. Banni H. Guerbej E.A. Almeida A. Banaoui H. Boussetta Received: 13 July 2005 / Accepted: 5 March 2006 Springer-Verlag 2006 1 2 Abstract The potential use of acetylcholinesterase 3 (AChE) and metallothionein (MT) responses as bio- 4 marker of organophosphorous (OPs) and trace metal 5 were assessed in fish Seriola dumerilli exposed to 0, 6 4, 6 mg/kg of malathion for 2, 7 and 13 days, and to 7 0, 50, 100, 250 μg/Kg of Cd for 2 days. Brain AChE 8 was significantly inhibited after 2 and 7 days of 9 malathion exposure, in a dose–response manner, but 10 no inhibition was observed after 13 days of exposure. 11 When exposed to Cd for 2 days, S. dumerelli pre- 12 sented an increase in AChE activity at a concentra- 13 tion of 50μg/Kg, but a strong and dose-dependent 14 AChE inhibition at 100 and 250 μg/Kg. Cd treatment also caused a rapid increase in MTs concentration in 15 liver, even at the lower concentration. Our experi- 16 ments indicate that the measurement of hepatic MT 17 concentration and brain AChE activity in S. dumerilli 18 would be useful biomarkers of OP and Cd exposure 19 and/or effects. 20 Keywords Acetylcholinesterase Æ Biomarkers Æ 21 Cadmium Æ Malathion Æ Metallothionein Æ Metals Æ 22 Organophosphorous Æ Seriola dumerilli 23 Introduction 24 J. Jebali Æ M. Banni Æ H. Boussetta ( * ) Laboratoire de Biochimie et de Toxicologie Environnementale, Ecole Supe ´ rieure d’Horticulture et d’Elevage, Chott-Marie ` m 4042, Tunisia e-mail: hamadi.boussetta@laposte.net Tel.: +216-73-348-546/544 Fax: +216-73-348-691 H. Guerbej Centre de Monastir, Institut National des Sciences et Technologie de la Mer, INSTM, Monastir, Tunisia E.A. Almeida Departamento de Bioquﾕ´ mica, Instituto de Quﾕ ´mica, Universidade de Sa ﾗ o Paulo, CP 26077, 05513-970 Sa ﾗ o Paulo, Brasil A. Banaoui Laboratoire Eau et Environnement, Faculte ´ des sciences, Universite ´ Ibn z ohr, Agadir, Maroc Marine littoral ecosystem and estuaries becomes an 25 area of concern because it constitutes the final 26 receptacle of anthropogenic discharge of pollutants. 27 Many pollutants including pesticides and heavy 28 metals reaches the marine environmental through 29 rivers, the atmosphere, agricultural and industrial run- 30 offs, threatening species inhabiting this ecosystem 31 (Craneet al. 2002; Banni 2004). The organophos- 32 phorus pesticide (OP) malathion is a common 33 insecticide used widely in agriculture (Lundebye 34 et al. 1997). In spite of replacement of organochlo- 35 rine (OC), excessive use of OPs in the treatment of 36 phytopathologies of cereals in the north of Tunisia 37 have threaten Bizerte lagoon ecosystem, especially at 38 the raining season (Dellali et al. 2001). 39 The primary toxic action of OPs on organisms is 40 the irreversible inhibition of the acetylcholinesterase 41 Journal : FISH Dispatch : 15-3-2006 Pages : 6 PIPS No. : DO00027804 h LE h TYPESET MS Code : FISH18R2 h CP h DISK 4 4 123