The Effect of Mercury on Sodium Transport Across a Cane Toad (Bufo Marinus) Skin Epithelium Essay Example
The Effect of Mercury on Sodium Transport Across a Cane Toad (Bufo Marinus) Skin Epithelium
Tchong Lioong CHEUNG KAI SUET
School of Biomedical, Bimolecular and Chemical Sciences, Department of Physiology, The University of Western Australia, Crawley,
Australia 6009.
Received 23rd April 2012; revised 7th May 2012; accepted 7th July 2012
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Abstract Mercuric Chloride (HgCl2) was used to investigate apical Sodium (Na) ion transport across the skin epithelia in a Cane toad (Bufo Marinus) by monitoring the short circuit current (SCC) and open circuit voltage across the abdominal skin. The skin was mounted in a Ussing chamber where different concentrations of HgCl2 was used on the pond side and belly side of the skin to observe its effects. High doses of mercury caused the SCC and Voc to fall to zero which can be interpreted as the blockage of Epithelial Sodium Channels (ENaCs) where the flow of Na is interrupted thus reducing the SCC.
Introduction The Bufo Marinus toad was introduced in Australia in 1935 and was released in the districts of Bundaberg, Mackay and northeastern Queensland as a means to control invertebrate pests in cane plantations whereby the name ‘Cane Toad’ originally came from (Covacevich & Archer, 1975). Since its introduction, the Cane Toad population in the state of Queensland have multiplied exponentially up to a point that it has become a pest and an invasive species that is endangering the natural biodiversities in Australia (Urban et al. 2007). To be able to mitigate and control the invasion of the Cane Toads, a deeper understanding of their physiology is required and in this experiment, we will focus mainly on the toad’s ability to absorb water osmotically through the abdominal skin (Brekke et al. 1991). The water absorption mechanism relies mainly on the change in osmolarity between the extracellular fluids and intracellular fluids. This is
Tchong Lioong CHEUNG KAI SUET
School of Biomedical, Bimolecular and Chemical Sciences, Department of Physiology, The University of Western Australia, Crawley,
Australia 6009.
Received 23rd April 2012; revised 7th May 2012; accepted 7th July 2012
_____________________________________________________________________________
Abstract Mercuric Chloride (HgCl2) was used to investigate apical Sodium (Na) ion transport across the skin epithelia in a Cane toad (Bufo Marinus) by monitoring the short circuit current (SCC) and open circuit voltage across the abdominal skin. The skin was mounted in a Ussing chamber where different concentrations of HgCl2 was used on the pond side and belly side of the skin to observe its effects. High doses of mercury caused the SCC and Voc to fall to zero which can be interpreted as the blockage of Epithelial Sodium Channels (ENaCs) where the flow of Na is interrupted thus reducing the SCC.
Introduction The Bufo Marinus toad was introduced in Australia in 1935 and was released in the districts of Bundaberg, Mackay and northeastern Queensland as a means to control invertebrate pests in cane plantations whereby the name ‘Cane Toad’ originally came from (Covacevich & Archer, 1975). Since its introduction, the Cane Toad population in the state of Queensland have multiplied exponentially up to a point that it has become a pest and an invasive species that is endangering the natural biodiversities in Australia (Urban et al. 2007). To be able to mitigate and control the invasion of the Cane Toads, a deeper understanding of their physiology is required and in this experiment, we will focus mainly on the toad’s ability to absorb water osmotically through the abdominal skin (Brekke et al. 1991). The water absorption mechanism relies mainly on the change in osmolarity between the extracellular fluids and intracellular fluids. This is