Hippocampal pyramidal neurons

Figures 2.5 and 2.6 shows some experimental records illustrating the function of these channels. Figure 2.5 illustrates the function of SKca channels in a hippocampal pyramidal neuron. In the record marked control in Fig. 2.5(b) the neuron was depolarised by injecting a 1-s long depolarising current. This makes it fire action...

FIGURE 24-1 Phosphotyrosine staining of a hippocampal neuron. A cultured rat hippocampal pyramidal neuron is stained with an antiphosphotyrosine antibody and detected by a secondary antibody conjugated to rhodamine. The staining reflects the presence of tyrosine-phosphorylated proteins throughout the neuron, including the cell body and synaptic regions. 

Nusser, Z., Sieghart, W Benke, D Fritschy, J. M and Somogyi, P. (1996) Differential synaptic localization of two major y-aminobutyric acid type A receptor a subunits on hippocampal pyramidal neurons. Proc. Natl. Acad. Sci. USA 93,11939-11944. 

Scholz WK. (1994). An ibotenate-selective metabotropic glutamate receptor mediates protein phosphorylation in cultured hippocampal pyramidal neurons. J Neurochem. 62(5) 1764-72. 

CYPIBI mRNA in male and female Rhesus monkey frontal cortex, hippocampus, thalamus, and amygdala CYPIBI protein colocalized with mRNA in female brains but restricted to hippocampal pyramidal neurons in male brains (Scallet et al., 2005). 

IHC shows CYP2B6 in neurons and astrocytes, higher in smokers and alcoholics especially in cerebellar Purkinje cells and hippocampal pyramidal neurons, also caudate nucleus and putamen (Miksys et al., 2003). 

Huag T, Storm JF (2000) Protein kinase A mediates the modulation of the slow Ca2+-dependent K+ current, lsAHP,by the neuropeptides CRF, VIP, and CGRP in hippocampal pyramidal neurons. J Neurophysiol 83 2071-2079 Huang Y, Li X-C, Kandel ER (1994) cAMP contributes to mossy fiber LTP by initiating both a covalently mediated early phase and macromolecular synthesis-dependent late phase. Cell 79 69-79... 

Nakatomi, H., Kuriu, T., Okabe, S., Yamamoto, S., Hatano, O., Kawahara, N., Tamura, A., Kirino, T., Nakafuku, M. (2002). Regeneration of hippocampal pyramidal neurons after ischemic brain injury by recruitment of endogenous neural progenitors. Cell, 110, 429-41. 

Helmut Haas and colleagues showed that, in hippocampal pyramidal neurons, H2-receptor stimulation potentiates excitatory signals by decreasing a Ca2+-activated K+ conductance, presumably via cAMP production [11], H2-receptor activation depolarizes thalamic relay neurons slightly, increasing markedly apparent membrane conductance, a response due to enhancement of the hyperpolarization-activated cation current lh [20],... 

Brundege JM, Dunwiddie TV (1996) Modulation of excitatory synaptic transmission by adenosine released from single hippocampal pyramidal neurons. J Neurosci 16 5603-12 Burkey TH, Quock RM, Consroe P, Ehlert FJ, Hosohata Y, Roeske WR, Yamamura HI (1997) Relative efficacies of cannabinoid CB1 receptor agonists in the mouse brain. Eur J Pharmacol 336(2-3) 295-8... 

Meucci, O., and Miller, R.J. (1996). gpl20-induced neurotoxicity in hippocampal pyramidal neuron cultures Protective action of TGF-betal. J. Neurosci. 16, 4080-4088. 

Ni, B., Wu, X., Su, Y., Stephenson, D., Smalstig, E. B., and Clemens, J. (1998). Transient global forebrain ischemia induces a prolong expression of the caspase-3 mRNA in rat hippocampal pyramidal neurons.. Cereb. Blood Flow Metab. 18, 248—256. 

In cortical neurons, 5-HT application excited and inhibited different cortical neurons (82,83), although the predominant effect of 5-HT was an inhibition of spontaneous firing (82,84-86). Similar actions have been described in other neuronal types such as midbrain periaqueductal gray neurons (87) and hippocampal pyramidal neurons (88-90). 

Fig. 2. Hyperpolarizing effects of 5-HT on the medial prefrontal cortex and hippocampal pyramidal neurons. (A) Bath application of 5-HT (30 pM) elicited a hyperpolarizing response that was blocked by BMY 7378 (3 pM). The lower trace shows that the selective 5-HT1A agonist 8-OH-DPAT (30 M) induced a membrane hyperpolarization comparable to that elicited by 5-HT (30 pM). Reproduced with permission from ref. 75. (B) Bath application of 5-carboxyamidotryptamine (5-CT) and 5-HT produced a similar membrane hyperpolarization in CA1 hippocampal pyramidal cells. The lower panels show the inability of 5-HT and 5-CT to elicit the hyperpolarizing response in presence of the 5-HT1A receptor antagonist WAY-100635. Reproduced with permission from ref. 76.

Vasilyev DV, Barish ME. Postnatal development of the hyperpolarization-activated excitatory current Ih in mouse hippocampal pyramidal neurons. J Neurosci 2002 22 8992-9004. 

Church J, Fletcher EJ. 1995. Blockade by sigma site ligands of high voltage-activated Ca2+ channels in rat and mouse cultured hippocampal pyramidal neurones. Br J Pharmacol 116 2801-2810. 

Sullivan JM. 1999. Mechanisms of cannabinoid-receptor-mediated inhibition of synaptic transmission in cultured hippocampal pyramidal neurons. J Neurophysiol 82 1286-1294. 

Kondratskaya, E. L. Krishtal, O. A. Effects of Ginkgo hiloha extract constitutents on glycine-activated strychnine-sensitive receptors in hippocampal pyramidal neurons of the rat. Neurophysiology, 2002, 34 155-157. 

Nakayama AY, Harms MB, Luo L (2000) Small GTPases Rac and Rho in the maintenance of dendritic spines and branches in hippocampal pyramidal neurons. J Neurosci 20 5329-5338... 

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