Biology (Neuroscience)

Results

The presence of the Tyrosine-hydroxylase protein was observed through the breaking down of the substrate of the DAB stain by the complex formed between the biotin in the secondary antibody and the avidin in the ABC Reagent. The recorded observations included a middle section and a top section of stage 11 embryonic mouse brains. The other sections on the slide were either torn, possibly from a shifting of the coverslip, or revealed no prominent staining.

The first embryonic midbrain section that was looked at showed stained areas located contralaterally to each other in regards to the cleft of the midbrain (Figure 1). Upon closer inspection, a slightly larger concentration of stained proteins was observed clustered together within the left side of the cleft (Figure 2) than the right (Figure 3), with the stained proteins of the left portion located more laterally than medially in regards to the cleft. However both stained regions remained fairly symmetrical to one another in regards to protein concentration. Comment by Paola Sacchetti: IHC is not quantitative but qualitative. You should just talk in general about number of positive cells rather than amounts of proteins really expressed

The second section revealed less empty stained protein pockets in comparison to the first section (Figure 4), showing a more continuous ring of the stained proteins ventrally and contralaterally to the cleft than what was observed in the first section (Figure 1). While the first section showed only a handful of stained proteins in the ventral region of the cleft (Figure 1) and to the right of the cleft (Figure 3), the second section contained a thicker stained section with more proteins, both ventrally to the cleft (Figure 5) and in the right lateral region of the cleft (Figure 6), possibly revealing a stage of development that was slightly older than the development stage of the first observed section. The stained portion of the left lateral region appeared to have spread more ventrally below the midbrain region of the section (Figure 4 and Figure 7) in comparison to the left lateral region of the first section (Figure 2), a possible result of the section containing tissue from another part of the brain besides just the midbrain region. Comment by Paola Sacchetti: You are looking at E11 embryo so the tissue is all the same age. But you are looking a different sections anterior to posterior so one section might be more at the beginning of the ventral midbrain, the 2nd section is in the middle of the structure where there are already more cells presents.