Lateral septum

Tang J, Wagner S, Schachner M, Dityatev A, Wotjak CT (2003) Potentiation of amygdaloid and hippocampal auditory evoked potentials in a discriminatory fear-conditioning task in mice as a function of tone pattern and context. Eur J Neurosci 18 639-650 Thomas E (1988) Forebrain mechanisms in the relief of fear the role of the lateral septum. Psychobiology 16 36-44... 

Striatum and lateral septum. Interestingly, in contrast to our findings in the hippocampus, CRH has biphasic effects in these brain structures. Low doses of CRH (0.1 and 0.3 pg) were found to decrease extracellular levels of 5-HT. Higher doses of CRH (1.0 and 3.0 pg) have, however, no effect or increase 5-HT levels in the striatum and lateral septum (Price et al. 1998 Price and Lucki 2001). The biphasic effects on levels of 5-HT in these brain regions may be related to the dose-dependent effects of CRH on the firing rate of DRN 5-HT neurones as described above. Interestingly, local injection of CRH in the DRN results in a decrease in extracellular 5-HT in the striatum and septum (Price and Lucki 2001). 

The nonapeptide vasopressin (AVP) is synthesized in the paraventricular nucleus of the hypothalamus (PVN) and the nucleus supraopticus. Besides its role in fluid regulation, AVP is also a key modulator of the HPA system, where it potentiates the effects of CRH on adrenocorticotropic hormone (ACTH) release. Extrahypothalamic AVP-containing neurons are localized in the medial amygdala and the bed nucleus of the stria terminalis. AVP applied intracere-broventricularly or to the lateral septum has been shown to affect cognition, social behavior, and anxiety-like behavior in rodents (Insel et al. 2001). 

The junction between the MPOA and lateral preoptic areas is the ventral part of the bed nucleus of the stria terminalis (ventral BST), and excitotoxic lesions disrupt retrieval behaviors and other aspects of maternal behavior in postpartum rats (Numan and Numan, 1996). Strong ventral BST projections to the lateral septum, substantia innominata, PVN, VTA, periaque-dutal gray matter, retrorubral field, and the region surrounding the locus coeruleus (Numan and Numan, 1996). 

Benzodiazepines also act on two other brain regions that we have discussed in relation to anxiety. One of these areas is the lateral septum. The septum, as you will recall, is involved in the expression of aggressive behavior. Curiously, benzodiazepines infused into the lateral part of the septum decrease electric probe burying but do not interfere with... 

The highest density of 5-HT1A receptors is found in limbic structures (the lateral septum, hippocampal formation, frontal and entorhinal cortices) and the... 

In addition to in vitro cell models, opioid agonists could induce the rapid endocytosis of the receptor in organo cultures or primary neuronal cultures, and also neurons in vivo. Treatment of longitudinal muscle-myenteric plexus preparation or the primary hippocampal neuron cultures with DAMGO resulted in internalization of the mu opioid receptor [146,147]. Similar observation was obtained with fluorescently labeled opioid peptides Fluo-dermorphin and Fluo-deltorphin [148]. Within 15 min of an intra-peritoneal injection of etorphine, mu opioid receptor immunoreactivity was observed in the endosomal structures of the myenteric neurons of guinea pig ileum [149]. Again, rapid clustering of a spliced variant of mu opioid receptor MOR-1C was observed in the lateral septum of the mouse after intracere-... 

Apart from the lateral septum, there is no indication that dysbindin-1 is enriched in hippocampal or subicular output to extrinsic structures. Nor is there any evidence that the protein is enriched in extrinsic input to the hippocampal formation, except perhaps for minor dopaminergic input from the mesolimbic pathway originating in the ventral tegmental area of the midbrain (Murotani et al., 2007 see O Section 2.2.6A.2.7). Otherwise, dysbindin-1 neuropil in the hippocampal formation appears to be selectively concentrated in the intrinsic associational and commissural projections of that structure. 

Double retrograde labeling of the VTA neurons from the frontal cortex, lateral septum, NAc, CPu and lateral habenula did not point out a highly divergent collateralization of VTA neurons (Albanese and Minciacchi, 1983). VTA neurons bifurcating to more than one target did not seem to exceed 10% of the total labeled population, and were relatively numerous when the injections were placed in the frontal cortex, lateral septum or lateral habenula (see also Section 8.2). 

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