Though I do not work in this area myself, I can certainly point you to the work of several colleagues who have done a great deal to advance our understanding in this area of ecotox inquiry.  Some examples of their work to get you started...

http://onlinelibrary.wiley.com/doi/10.1002/tox.20477/abstract

http://link.springer.com/article/10.1007/s00244-001-0013-6

http://link.springer.com/article/10.1007/s002440010270

I hope these are helpful to your research!

Cheers,

Michael

Many thanks Michael for your suggestions! These papers are indeed helpful to my research. I have read two of these great papers and some others before but authors typically documented the higher Hsp70 in chlorpyrifos-contaminanted animals while it is likely that I found an opposite pattern. Only Scheil et al. 2009 somewhat mentioned about the decrease in Hsp70, yet I still need some more obvious examples, if exist, about the decrease Hsp70 in chlorpyrifos- or organophosphate insecticide-exposed animals!

Greetings,

Khuong

Khuong,

I suspected that you had already encountered the results of these workers, but they were the first to come to mind.  Again, though I do not work in this field as such, as many of my colleagues do, I have developed some fundamental familiarities with (and of course great interest in) the topic. Indeed, one of my friends in graduate school (see e.g. Cruz-Rodriguez and Chu, 2002 Aquatic Toxicol. 60, 157-168) worked with PAH induction of Hsp70 in lab- and field-exposed Eastern oysters and he taught me a lot about Hsp70 in those organisms :-)  

That you are seeing a decrease in your organisms is quite fascinating!  With what organism(s) are you working?  A quick perusal of my personal lit archives turned up an interesting reference to a review paper (that, unfortunately, I do not have a copy of) by Kammenga et al. wherein they discuss some work that has shown decreased levels in response to contaminant exposures.  Might be worth a closer look if you are not already familiar with the study.  Here is the citation...

Kammenga et al. 2000. Rev Environ Contam Toxicol 164:93–147.

My quick perusal of my own lit archives also turned up another paper indicating some reduced Hsp70 in metal-exposed soil arthropods (organisms with which I have worked extensively over the years, so I have a considerable collection of ecotox literature on these critters).  If you are not already familiar with this work, it may be of some value to you...

Kohler et al. 2000. J. Evol. Biol. 13, 569-582.

Good luck and I will be interested to learn what you find.

Michael

HI Michael,

The papers of Kammenga et al. 2000 and Kohler et al. 2000 were great. They indeed discuss some work that has shown decreased levels in response to contaminant exposures that may have also occured in my animals. My study is dealing with combined effects of global warming and pollutant stress on damselflies. In this experiment, I am working with damselfly larvae that I collected from a pond situated within a nature reserve surrounded by agriculture. Therefore, it is possible that larvae had been exposed to low doses of pesticides in their pond of origin.

You have a great collection of ecotox literature :) I will keep you updated with this experiment.

Thank you very much for your great help. Also good luck with your research!

Greetings,

Khuong

Khuong,

Glad the papers were helpful.  They certainly looked relevant and intriguing to me.  

Sounds like you are immersed in a fascinating study. Though most of my core work has been in terrestrial systems over the past several years (in part driven by good funding opportunities and my desires to expand my horizons into the areas of soil ecology and ecotox), my interests in the ecology and ecotoxicology of freshwater systems goes back to my first Biology class as a university freshman.  So, I will look forward to keeping up with your progress as your study evolves.  And if I can assist in any small way, please let me know.

All the best!

Michael

Many thanks Michael for your great help and your willingness to help me in the future!

I like very much my research topic and hope I can continue with this after my PhD :)

All the best!

Khuong