PMID- 21847660
OWN - NLM
STAT- MEDLINE
DCOM- 20120117
LR  - 20211020
IS  - 1573-3017 (Electronic)
IS  - 0963-9292 (Linking)
VI  - 20
IP  - 7
DP  - 2011 Oct
TI  - Mercury, selenium and neurochemical biomarkers in different brain regions of 
      migrating common loons from Lake Erie, Canada.
PG  - 1677-83
LID - 10.1007/s10646-011-0754-6 [doi]
AB  - Common loons (Gavia immer) can be exposed to relatively high levels of dietary 
      methylmercury (MeHg) through fish consumption, and several studies have 
      documented MeHg-associated health effects in this species. To further study the 
      neurological risks of MeHg accumulation, migrating loons dying of Type E botulism 
      were collected opportunistically from the Lake Erie shore at Long Point (Ontario, 
      Canada) and relationships between total mercury (THg), selenium (Se), and 
      selected neurochemical receptors and brain enzymes were investigated. THg 
      concentrations were 1-78 mug/g in liver; and 0.3-4 mug/g in the brain (all 
      concentrations reported on a dry weight basis). A significant (p < 0.05) positive 
      correlation was found between THg in liver and THg in 3 subregions of the brain 
      (cerebral cortex: r = 0.433; cerebellum: r = 0.293; brain stem: r = 0.405). THg 
      varied significantly among different brain regions, with the cortex having the 
      highest concentrations. Se levels in the cortex and cerebellum were 1-29 and 1-10 
      mug/g, respectively, with no significant differences between regions. Se was not 
      measured in brain stem due to insufficient tissue mass. There were molar excesses 
      of Se over mercury (Hg) in both cortex and cerebellum at all Hg concentrations, 
      and a significant positive relationship between THg and the Hg:Se molar ratio 
      (cortex: r = 0.63; cerebellum: r = 0.47). No significant associations were 
      observed between brain THg and the N-methyl-D-aspartic acid (NMDA) receptor 
      concentration, nor between THg and muscarinic cholinergic (mACh) receptor 
      concentration; however, brain THg levels were lower than in previous studies that 
      reported significant Hg-associated changes in neuroreceptor densities. Together 
      with previous studies, the current findings add to our understanding of Hg 
      distribution in the brain of common loons, and the associations between Hg and 
      sub-lethal neurochemical changes in fish-eating wildlife.
FAU - Hamilton, Melanie
AU  - Hamilton M
AD  - Environment Canada, National Wildlife Research Center, Carleton University, 
      Ottawa, ON, Canada.
FAU - Scheuhammer, Anton
AU  - Scheuhammer A
FAU - Basu, Niladri
AU  - Basu N
LA  - eng
PT  - Journal Article
DEP - 20110817
PL  - United States
TA  - Ecotoxicology
JT  - Ecotoxicology (London, England)
JID - 9885956
RN  - 0 (Biomarkers)
RN  - 0 (Neurotransmitter Agents)
RN  - 0 (Receptors, Muscarinic)
RN  - 0 (Receptors, N-Methyl-D-Aspartate)
RN  - 0 (Water Pollutants, Chemical)
RN  - EC 3.1.1.8 (Cholinesterases)
RN  - FXS1BY2PGL (Mercury)
RN  - H6241UJ22B (Selenium)
SB  - IM
MH  - Animals
MH  - Biomarkers
MH  - *Birds
MH  - Brain/*metabolism
MH  - Cholinesterases/metabolism
MH  - Environmental Monitoring/methods
MH  - Fishes
MH  - Great Lakes Region
MH  - Lakes
MH  - Linear Models
MH  - Liver/chemistry
MH  - Mercury/*analysis
MH  - Neurochemistry
MH  - Neurotransmitter Agents/analysis
MH  - Ontario
MH  - Receptors, Muscarinic/analysis
MH  - Receptors, N-Methyl-D-Aspartate/metabolism
MH  - Selenium/*analysis
MH  - Tissue Distribution
MH  - Water Pollutants, Chemical/*analysis
EDAT- 2011/08/19 06:00
MHDA- 2012/01/18 06:00
CRDT- 2011/08/18 06:00
PHST- 2011/07/21 00:00 [accepted]
PHST- 2011/08/18 06:00 [entrez]
PHST- 2011/08/19 06:00 [pubmed]
PHST- 2012/01/18 06:00 [medline]
AID - 10.1007/s10646-011-0754-6 [doi]
PST - ppublish
SO  - Ecotoxicology. 2011 Oct;20(7):1677-83. doi: 10.1007/s10646-011-0754-6. Epub 2011 
      Aug 17.