Functions dendritic spines

Saez ET, Pehar M, Vargas MR, Barbeito L, Maccioni RB (2006) Production of nerve growth factor by beta-amyloid-stimulated astrocytes induces p75NTR-dependent tau hyperphosphorylation in cultured hippocampal neurons. J Neurosci Res 84 1098-1106 Sala C, Roussignol G, Meldolesi J, Fagni L (2005) Key role of the postsynaptic density scaffold proteins Shank and Homer in the functional architecture of Ca homeostasis at dendritic spines in hippocampal neurons. J Neurosci 25 4587 592 Santello M, Volterra A (2008) Synaptic modulation by astrocytes via Ca(2-l-)-dependent glutamate release. Neuroscience 158 253-9... 

To perform its unique functional role each neuron must regulate a host of intracellular activities, that occur in axons and dendrites distant from the cell nucleus. For example, axonal guidance during development, or remodeling of dendritic spines in response to local input, each involves many different complex control systems that are highly localized and largely autonomous. [ 1 ]. 

Sala, C., Piech, V., Wilson, N. R. et al. Regulation of dendritic spine morphology and synaptic function by Shank and Homer. Neuron 31 115-130, 2001. 

The adult brain is endowed with nuclear as well as cytosolic and membrane T3 receptors that have been visualized by autoradiography and studied biochemically [30-33]. Both neurons and neuropil are labeled by [ 1251]T3, and the labeling is selective across brain regions. Functionally, one of the most prominent features of neural action of thyroid hormone in adulthood is subsensitivity to norepinephrine as a result of a hypothyroid state [27], These changes may be reflections of loss of dendritic spines in at least some neurons of the adultbrain. Clinically, thyroid hormone deficiency increases the probability of depressive illness, whereas thyroid excess increases the probability of mania (Ch. 52) in susceptible individuals [27],... 

Kasai H, Matsuzaki M, Noguchi J, et al (2003) Structure-stability-function relationships of dendritic spines. Trends Neurosci 26 360-368... 

Sala, C., Roussignol, G., Meldolesi, J., and Fagni, L. (2005). Key role of the postsynaptic density scaffold proteins Shank and Homer in the functional architecture of Ca2+ homeostasis at dendritic spines in hippocampal neurons. J. Neurosci. 25, 4587-4592. 

Thus, a GSH deficit has consequences consistent with the concept of functional disconnectivity, as hypofunction of NMDA-R and alteration of dopamine signaling have been observed. When imposed on animals during development, a GSH deficit induces also a structural disconnectivity, as revealed by the decrease in dendritic spines and parvalbumin-immunoreactivity of inhibitory intemeurons in the prefrontal cortex Finally, a transient GSH deficit during brain development causes deficits in visual recognition and olfactory integration. 

Studies at the ultrastructural level in the rat NAc shell showed that 65% of D4 receptors were contained in axons and axon terminals, in plasma and vesicular membranes, while only 22% were located in dendrites and dendritic spines which received input from TH-positive terminals (Svingos et al., 2000). The labeled terminals formed occasionally asymmetrical synapses, and only about 17% of them exhibited TH immunoreactivity. In the NAc, therefore, the D4 receptor appears to be involved in presynaptic rather than postsynaptic functions (Svingos et al., 2000). 

Lin B, Kramar EA, Bi X, Brucher FA, Gall CM, Lynch G (2005) Theta stimulation polymerizes actin in dendritic spines of hippocampus. J Neurosci 25 2062-2069 Lonze BE, Ginty DD (2002) Function and regulation of CREB family transcription factors in the nervous system. Neuron 35 605-623... 

Ryu J, Liu L, Wong TP, Wu DC, Burette A, Weinberg R, Wang YT, Sheng M (2006) A critical role for myosin 11b in dendritic spine morphology and synaptic function. Neuron 49 175-182... 

Yuste, R., Denk, W. (1995). Dendritic spines as basic functional units of neuronal integration. Nature 375 682. ... 

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