The amygdala is an anatomically heterogeneous structure involved in complex behavioral processes, such as generation of appropriate autonomic, endocrine and motor responses to emotionally sensory stimuli, emotional learning and modulation of the formation of memories for emotionally arousing events. Cortical and thalamic sensory information enters the amygdala mainly via the lateral nucleus, which provides the most extensive intra-amygdaloid projections. Calretinin has proved to be useful marker for labeling the subpopulations of neurons in the lateral nucleus of the rat and human amygdala. In the present study, we investigated the distribution of calretinin-immunoreactive (IR) neurons in the lateral amygdalar nucleus of the Bottlenose dolphin (Tursiops truncatus). From three brains, sections through the whole rostrocaudal extent of the amygdala were stained immunohistochemically with a monoclonal antibody raised against calretinin. Based on the shape and size of the soma and on the morphology of the dendrites, we divided the calretinin-IR neurons into two major categories: pyramidal and non-pyramidal. Pyramidal cells had large (mean area of 271,1 µm2 ± 69,3), lightly stained, pyramidal somata. Only the proximal dendrites were stained. Non-pyramidal neurons were divided into three morphologic types: spheroidal, polygonal and fusiform. Spheroidal neurons had a spherical soma and 3 to 5 dendrites, which were about equal thickness. The somal size of these neurons were 80,6 µm2 ± 17,2. Polygonal neurons had an angular somata (mean area of 186,6 µm2 ± 72,9) and 3 to 5 primary dendrites of variable thickness. Fusiform neurons had a spindle-shaped somata (mean area of 112,6 µm2 ± 39,9) that emanated primary dendrites from the opposite pole of the cell body. Morphologically the majority of calretinin-IR cells resemble inhibitory neurons. This result suggest that calretinin containing neurons may have and important role in the inhibitory network of the lateral nucleus of the dolphin amygdala
DISTRIBUTION OF CALRETININ IMMUNOREACTIVITY IN THE LATERAL NUCLEUS OF THE DOLPHIN AMYGDALA
RAMBALDI, ANNA MARIA;GARDINI, ANNA;GRANDIS, ANNAMARIA;CANOVA, MARCO;BIANCO, FRANCESCA;LATORRE, ROCCO;DE GIORGIO, ROBERTO;BOMBARDI, CRISTIANO
2014
Abstract
The amygdala is an anatomically heterogeneous structure involved in complex behavioral processes, such as generation of appropriate autonomic, endocrine and motor responses to emotionally sensory stimuli, emotional learning and modulation of the formation of memories for emotionally arousing events. Cortical and thalamic sensory information enters the amygdala mainly via the lateral nucleus, which provides the most extensive intra-amygdaloid projections. Calretinin has proved to be useful marker for labeling the subpopulations of neurons in the lateral nucleus of the rat and human amygdala. In the present study, we investigated the distribution of calretinin-immunoreactive (IR) neurons in the lateral amygdalar nucleus of the Bottlenose dolphin (Tursiops truncatus). From three brains, sections through the whole rostrocaudal extent of the amygdala were stained immunohistochemically with a monoclonal antibody raised against calretinin. Based on the shape and size of the soma and on the morphology of the dendrites, we divided the calretinin-IR neurons into two major categories: pyramidal and non-pyramidal. Pyramidal cells had large (mean area of 271,1 µm2 ± 69,3), lightly stained, pyramidal somata. Only the proximal dendrites were stained. Non-pyramidal neurons were divided into three morphologic types: spheroidal, polygonal and fusiform. Spheroidal neurons had a spherical soma and 3 to 5 dendrites, which were about equal thickness. The somal size of these neurons were 80,6 µm2 ± 17,2. Polygonal neurons had an angular somata (mean area of 186,6 µm2 ± 72,9) and 3 to 5 primary dendrites of variable thickness. Fusiform neurons had a spindle-shaped somata (mean area of 112,6 µm2 ± 39,9) that emanated primary dendrites from the opposite pole of the cell body. Morphologically the majority of calretinin-IR cells resemble inhibitory neurons. This result suggest that calretinin containing neurons may have and important role in the inhibitory network of the lateral nucleus of the dolphin amygdalaI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
