0000000000113804
AUTHOR
Vicent Teruel
Fiber Connections of the Amygdaloid Formation of the Lizard <i>Podarcis hispanica</i>
The amygdaloid formation of the lizard Podarcis hispanica can be divided into three main groups of nuclei on the basis of their input from the main and accessory olfactory bulbs: the vomeronasal amygdala, the olfactory amygdala and the dorsal amygdaloid group, the latter group receiving afferents from neither the main (MOB) or the accessory olfactory bulb (AOB). The vomeronasal amygdala has a centrifugal projection to the AOB, an important commissural connection to the contralateral vomeronasal amygdala, a minor projection to nucleus accumbens, and a bilateral projection to the lateral cortex. The olfactory amygdala displays a bilateral afferents from the MOB, receives a contralateral affer…
Afferent and efferent connections of the olfactory bulbs in the lizard Podarcis hispanica.
The connections of the olfactory bulbs of Podarcis hispanica were studied by tract-tracing of injected horseradish peroxidase. Restricted injections into the main olfactory bulb (MOB) resulted in bilateral terminallike labeling in the medial part of the anterior olfactory nucleus (AON) and in the rostral septum, lateral cortex, nucleus of the lateral olfactory tract, and ventrolateral amygdaloid nucleus. Bilateral retrograde labeling was found in the rostral lateral cortex and in the medial and dorsolateral AON. Ipsilaterally the dorsal cortex, nucleus of the diagonal band, lateral preoptic area, and dorsolateral amygdala showed labeled cell bodies. Retrogradely labeled cells were also foun…
Nucleus incertus contribution to hippocampal theta rhythm generation.
The hippocampal theta rhythm is generated by the pacemaker activity of the medial septum-diagonal band of Broca (MS/DBB) neurons. These nuclei are influenced by brainstem structures that modulate the theta rhythm. The aim of the present work is to determine whether the nucleus incertus (NI), which has important anatomical connections with the MS/DBB, contributes to the hippocampal theta rhythm generation in rats. Hippocampal field activity was recorded in urethane-anaesthetized rats. Electrical stimulation of the NI not only evoked theta rhythm in the hippocampus, but also decreased the amplitude of delta waves. Unit recordings in the NI revealed either a non-rhythm discharge pattern in mos…
Cytoarchitecture and efferent projections of the nucleus incertus of the rat
The nucleus incertus is located caudal to the dorsal raphe and medial to the dorsal tegmentum. It is composed of a pars compacta and a pars dissipata and contains acetylcholinesterase, glutamic acid decarboxylase, and cholecystokinin-positive somata. In the present study, anterograde tracer injections in the nucleus incertus resulted in terminal-like labeling in the perirhinal cortex and the dorsal endopyriform nucleus, the hippocampus, the medial septum diagonal band complex, lateral and triangular septum medial amygdala, the intralaminar thalamic nuclei, and the lateral habenula. The hypothalamus contained dense plexuses of fibers in the medial forebrain bundle that spread in nearly all n…
The GABAergic system of the dorsal cortex of lizards: a combined HRP-GABA immunohistochemistry study.
Abstract γ-Aminobutyric acid (GABA)-like immunoreactive (GABA-LI) neurons were found throughout the mediolateral and rostrocaudal axis of the dorsal cortex. They were horizontal, vertical and multipolar cells, mainly distributed in layers 1 and 3. GABA-LI boutons were diffusely distributed in layers 1 and 3, as well as forming basket-like images around layer 2 pyramidal perikarya. Double labelling experiments indicate that GABA-LI cells are an origin of and a target for rostrocaudal intrinsic projections within the dorsal cortex.