Hippocampus dissection

Figure 8.1 Diagram of hippocampus dissection procedure. (A) Removal of the brain from the embryo. From left to right (1) The embryo is grasped with a pair of large straight forceps the brain under the skull is visible. (2) Make the first cut at the brain...

Izquierdo I, Schroder N, Netto CA, Medina JH (1999) Novelty causes time-dependent retrograde amnesia for one-trial avoidance in rats through NMDA receptor- and CaMKII-dependent mechanisms in the hippocampus. Eur J Neurosci 11 3323-3328 Izquierdo LA, Barros DM, Vianna MR, Coitinho A, deDavid e Silva T, Choi H, Moletta B, Medina JH, Izquierdo I (2002) Molecular pharmacological dissection of short- and longterm memory. Cell Mol Neurobiol 22 269-287 Jacobs WJ, Nadel L (1985) Stress-induced recovery of fears and phobias. Psychol Rev 92 512-531... 

The areas dissected and the nomenclature are shown in Fig. 2. The results are mean values of 4-12 measurements from 1 to 7 different animals. ChAc values are expressed as //moles ACh synthesized/ h/g dry wt. and are taken from Fonnum (1970). AChE values are from Storm-Mathisen (1970) and are expressed as //moles acetylthiocholine hydrolysed/h/g dry wt. (hippocampus regio superior) or as //moles ACh hydrolysed/h/g dry wt. (area dentata). 

The zones dissected were the approximately 60 ftm wide mossy fibre layer, the subjacent 60 yum wide zone comprising the pyramidal layer, and an overlying 80 /im strip of stratum radiatum. Enzyme activities are expressed relative to those of strips cut at right angles through all layers of hippocampus regio superior. These were 37.0 4- 1.5 /imoles/h/g dry wt. for GAD and 18.0 1.6 /unoles/h/g dry wt. for ChAc. Mean values S.E.M. (numbers of samples) are given. The data are from 3 rats. 

Fig. 6. Distribution of GAD in different zones of hippocampus regio superior and area dentata. Presentation as in Fig. 3, dissection described in Fig. 2. The mean activity of samples cut through all layers of hippocampus regio superior (activity unit) was in the series from hippocampus 44.5 4.7 tmoles/h/g dry wt. (S.D., 18 samples) and in that from area dentata 44.0 4.0 jttmoles/h/g dry wt. (S.D.. 8 samples). The data were from two animals and the numbers of samples for the different zones were A 10, Oi 7, Oe 7, P 7, Ri 6, Rm 10, Re 4, L 7, M 11, M 8, G 9 and H 8. (Reproduced from J. Neurochem. (1971), Storm-Mathisen and Fonnum, 18, 1105-1111.)...

Fig. 1. C57BL/6 mice were acutely treated with 20 mg/kg morphine subcutaneously and separate sub groups treated chronically with either the same dose of morphine daily or saline. Mice were sacrificed 4 h after final injections and the brains quickly dissected to extract RNA for CBir gene expression study. The expression of CBir RNA was compared by real-time PCR using the gene-specific probe and primers. Acute and chronic treatment with 20 mg/kg morphine produced a reduction in the expression of CBir gene transcripts in the striatum (str), midbrain (mid), and hippocampus (hip).

Fig. 4. C57B1/6 mice were subjected to acute and chronic mild stress and assessed for anhedonia (CMS animals) by weekly sucrose consmnption. Mice were sacri eed at the end of wk 4 or following acute stress, and the brains were quickly dissected to extract RNA for CB2 cannabinoid receptor gene expression by real-time PCR system using the gene-speci c probe and primers (T aqMan real-time PCR system, ABl 7900). CB2 gene expression was detected in the acute and chronic mild stress mice in the striatum (str), midbrain (mid), and the hippocampus (hip).

Using the scalpel, make an incision at the level of the hippocampal fissure. With the small spatula, scoop the hippocampus from the underlying cortex. If the dissection is sufficiently rapid (<10 min), isolate the second hippocampus and slice along with the first hippocampus. 

Place the sliced hippocampus under a dissection microscope. Select slices having even margins and clear, uniform, well-defined pyramidal cell layers and plate on membrane inserts... 

The description of the dissection of these areas indicates presence of the hippocampus. 

Remove the brains from fetuses and collect them in DM/Ky-Mg solution in a 60-mm Petri dish. Under a dissecting microscope, carefully dissect out the hippocampus that fines the curved medial edge of the cerebral cortex. Remove the meninges and choroid plexes as much as possible. Collect the hippocampi to a 35-mm dish containing DM/Ky-Mg solution. 

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