I am an embryologist working with the frog embryo. I have suspicions
that at a particular early stage of development, ion currents (whether
between cells, or to the outside of the cell surface) play a role in
patterning an aspect of the embryo. I have gotten together a bunch of
drugs (such as amiloride, etc.) and found that in fact, letting the
embryos develop in media containing these drugs does cause a specific
defect in this process (having titered the doses to levels where no gross
abnormalities develop). I now want to be more specific in defining which
cells participate in these currents (I have a model which suggests a
prediction). So, I was hoping that someone could suggest for me a drug (or
drugs) which could be microinjected into specific cells of the early
embryo, and would a) stay there (except for being passed on with cell
division) and not diffuse to other cells, and b) would inhibit ion pumps,
pores, or channels. Can anyone email me any info on this? Do any of these
common drugs (amiloride, benzamil, etc.) work from inside the cell? Is it
known whether they get out of a cell, once injected into it? Any info
would be greatly appreciated. Please email directly to
mlevin at fas.harvard.edu. Thanks in advance!
Mike Levin