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- Lennquist, Anna, 1978, et al.
(författare)
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Responses in fish exposed to medetomidine, a new antifouling agent
- 2010
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Ingår i: Marine Environmental Research. - : Elsevier BV. - 0141-1136. ; 69
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Tidskriftsartikel (refereegranskat)abstract
- Medetomidine is being introduced as a new antifouling agent. As part of a large risk assessment campaign, we have studied responses to medetomidine in a number of fish species. The studied parameters include respiration, blood parameters, antioxidant enzymes, CYP1A, behaviour, pigmentation, reproduction and growth. The main observations from these studies are: 1. Body paleness at water concentrations in the range of 0.5-50 nM, depending on species. In addition, impaired adaptation to the background colour was shown in fry from turbot and lumpfish. In rainbow trout, desensitization of melanophores (pigment cells) occurred in fish exposed to medetomidine for 21 days, but a prolonged study (54 days exposure time), showed that the melanophores were well functioning and in addition that no apoptosis had occurred. 2. CYP1A activities, measured as EROD activities, were increased at medetomidine water concentrations from 0.5-5 nM in rainbow trout, Atlantic salmon, turbot and three-spined stickleback. However, investigations in vitro showed medetomidine to be a potent inhibitor of EROD activity. 3. In lumpfish and turbot fry, a decreased oxygen consumption and respiration rate was observed from 2 nM medetomidine. This effect was reversible to a large extent.
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| 3. |
- Lennquist, Anna, 1978, et al.
(författare)
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The major responses in fish exposed to medetomidine, a new antifouling agent
- 2009
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Ingår i: SETAC Europe. Göteborg, Sverige.
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Konferensbidrag (refereegranskat)abstract
- Medetomidine is being introduced as a new antifouling agent. As part of a large risk assessment, a number of studies in fish have been performed. Studied species are rainbow trout, Atlantic cod, turbot, Atlantic salmon, lumpfish and three-spined stickleback. Medetomidine has been administered either via water or via i.p injection, and exposure time has varied from one hour up to 54 days. Studied parameters include respiration, blood parameters, activities of antioxidant enzymes and CYP1A, behaviour, pigmentation and function of pigment cells, growth and growth-related hormones. From these studies have been observed that: 1. In all experiments the most pronounced effects were body paleness at water concentrations in the range of 0.5-50 nM depending on species. In Atlantic cod, turbot and lumpfish fry, medetomidine caused impaired adaptation to the background colour. In rainbow trout desensitization of melanophores (pigment cells) occurred in fish exposed to medetomidine for 17 days, but a prolonged study (54 days exposure time), showed that the melanophores were well functioning and in addition no apoptosis had occurred. 2. In lumpfish and turbot fry, a decreased oxygen consumption and respiration rate was observed at 2.1 nM medetomidine. This effect was reversible. 3. CYP1A activities, measured as EROD activities, were increased at medetomidine water concentrations from 0.5-5 nM in rainbow trout, Atlantic salmon, turbot and three spined stickleback, but also decreased activity has been observed in turbot. Investigations in vitro have shown medetomidine to be a potent inhibitor of EROD activity. 4. Other parameters studied have not been affected by medetomidine treatment at these concentrations.
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