Medial amygdala

Kevetter G.A. and Winans S. (1981). Connections of the cortico-medial amygdala in the golden hamster Mesocricetus auratus, 1. Efferents of the vomeronasal amygdala . J Comp Neurol 197, 81-98. 

Luiten G.M., Koolhaas J.M., de Boer S. and Koopmans S.J. (1985). The cortico-medial amygdala in the central nervous system organisation of agonistic behaviour. Brain Res 332, 283-297. 

Martinez-Marcos A. and Halpem M. (1999b). Differential projections from the anterior and posterior divisions of the accessory olfactory bulb to the medial amygdala in the opossum, Monodelphis domestica. Europ J Neurosci 11, 3789-3799. 

Petrulis A. and Johnston R. (1999). Lesions centered on the medial amygdala impair scent-marking and sex-odor recognition, but spare discrimination of individual odors in female golden hamsters. Behav Neurosci 113, 345-357. 

Binns, K.E. and Brennan, P. (2005) Changes in electrophysiological activity in the accessory olfactory bulb and medial amygdala associated with mate recognition in mice. Eur. J. Neurosci. 21, 2529-2537. 

Selective Response of Medial Amygdala Subregions to Reproductive and Defensive Chemosignals from Conspecific and Heterospecific Species... 

Fig. 35.1 Simplified diagram of chemosensory circuit in amygdala. Vomeronasal input via accessory olfactory bulb (VNO/ AOB) is analyzed in anterior and posterior medial amygdala (MeA, MeP). MeP appears to be inhibited by intercalated nucleus (ICNc) for heterospecific and artificial stimuli. MOE/ MOB Main olfactory epithelium/Main olfactory bulb. ACN Anterior Cortical Nucleus. PC Piriform Cortex. BLA Basolateral amygdala. ICNr rostral part of medial intercalated nucleus. ICNc caudal part of ICN. MPOA Medial Preoptic Area. VMH Ventro-medial hypothalamus...

Selective Response of Medial Amygdala Subregions to Chemosignals... 

Fig. 35.3 FRAs expression within medial amygdala and ICN averaged over sets of three serial sections from MeA to MeP - for hamster (top) and mouse (below). The same two stimuli were used, each conspecific for one species, where it activates MeA and MeP, and heterospecific for the other, where it activates MeA and ICN. Control values for hamster were taken from animals perfused 15 min after exposure to HVF, before significant FRAs expression begins.

The differential activation of subareas of MeP by reproductive and conspecific threat/defensive stimuli in hamster is generally consistent with the proposals of Canteras and colleagues (Cameras 2002, Petrovich, Cameras and Swanson 2001). From tracing experiments in rats, they suggest that medial amygdala is divided into subareas concerned with reproductive and defensive stimuli, each connected to sub-areas of the hypothalamus with the same function. Following these proposals, Choi,... 

Table 35.1 includes data from Choi et al. (2005) for comparison with our studies on activation of medial amygdala and subareas in hamsters and mice. They concentrated on whether cells with an identified phenotype respond to particular stimuli and project to the hypothalamic subnuclei predicted by the Canteras hypothesis, but did not systematically report on other cells or other areas. 

Baum, M. J. and Everitt, B. J. (1992) Increased expression of c-fos in the medial preoptic area after mating in male rats role of afferent inputs from the medial amygdala and midbrain central tegmental field. Neuroscience 50, 627-646. 

Meredith, M. and Westberry, J.M. (2004) Distinctive responses in the medial amygdala to same-species and different-species pheromones, J Neurosci. 24, 5719-25. 

Nolte, C, and Meredith, M. (2005). mGluR2 activation of medial amygdala input impairs vomeronasally-mediated behavior. Physiol. Behav. 86, 314-323. 

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). 

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