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Brain Research Bulletin Dec 1985The effects of iontophoretic administration of norepinephrine (NE) and dopamine (DA) on olfactory tubercle (OT) neurons that respond to lateral hypothalamus (LH) or...
The effects of iontophoretic administration of norepinephrine (NE) and dopamine (DA) on olfactory tubercle (OT) neurons that respond to lateral hypothalamus (LH) or locus coeruleus (LC) electrical stimulation were studied. NE and DA decreased the frequency of OT neurons which were increased or decreased by the LH stimulation. An increased firing of OT neurons following NE or DA administration was less frequently observed. NE administration decreased the firing of OT neurons that responded to LC stimulation. These results suggest that the LC fibers which reach the OT use NE as a neurotransmitter. DA administration also suppressed the unitary discharge of OT neurons responding to LC stimulation. The increase in frequency of OT neurons observed following LH stimulation cannot be attributed to DA. The possibility that other suspected neural transmitters are involved in this effect is discussed.
Topics: Animals; Central Nervous System; Dopamine; Evoked Potentials; Female; Iontophoresis; Male; Microinjections; Neurons; Norepinephrine; Olfactory Bulb; Olfactory Pathways; Rats; Rats, Inbred Strains; Reaction Time
PubMed: 4084818
DOI: 10.1016/0361-9230(85)90217-5 -
The Journal of Comparative Neurology Jan 1987The projections from the striatal part of the olfactory tubercle were examined in rats, both with the aid of experimental silver impregnation methods following...
The projections from the striatal part of the olfactory tubercle were examined in rats, both with the aid of experimental silver impregnation methods following superficial laminar heat lesions of the tubercle and by the use of anterograde transport of Phaseolus vulgaris-leucoagglutinin (PHA-L) following injections of the lectin in the dense cell layer of the tubercle. Retrograde transport of fluorescent substances following injections of the tracer in the multiform layer of the tubercle were used to corroborate the results obtained by the anterograde transport and degeneration methods. The main and apparently only significant termination from the striatal cells in the olfactory tubercle is located immediately deep to the dense cell layer in areas that could be identified as part of the ventral pallidum on the basis of either the Nissl method or glutamate decarboxylase immunocytochemistry. Whereas a mediolateral topography is generally maintained by the ventral striatopallidal pathway originating in the dense cell layer, there is a considerable spread of the projection in the rostrocaudal direction. The dense projection field of the olfactory tubercle component of the ventral striatopallidal pathway permeates the ventrolateral part of the ventral pallidum, thereby complementing the termination of the accumbens projection to the more mediodorsal parts of the ventral pallidum.
Topics: Animals; Corpus Striatum; Globus Pallidus; Male; Nerve Degeneration; Neural Pathways; Olfactory Bulb; Phytohemagglutinins; Rats; Rats, Inbred Strains; Synaptic Transmission; Thalamus
PubMed: 3029188
DOI: 10.1002/cne.902550409 -
Research Publications - Association For... 1992The results of the experiments described above suggest that although the abused psychomotor stimulants and opioids have independent actions that contribute to their... (Review)
Review
The results of the experiments described above suggest that although the abused psychomotor stimulants and opioids have independent actions that contribute to their reinforcing effects, there are common neuronal substrates for some of their rewarding effects. Additionally there is considerable evidence implicating dopamine systems in these rewarding effects. The neuronal systems involved in these pharmacological actions may be similar to those involved in the rewarding effects of electrical stimulation to the brain. Although both classes of compounds cause euphoria in humans and are reinforcing in animals, the opioids are also central nervous system depressant drugs. These depressant properties influence the subjective effects in humans and possibly the nature of the rewarding effect in animals. Experiments using the 2-deoxyglucose procedure indicate that BSR to either the ventral tegmental area or the medial forebrain bundle results in functional activation throughout the mesocorticolimbic system. The major effects are found in the nucleus accumbens, olfactory tubercle, and the medial prefrontal cortex. Cocaine produces increases in metabolic rates similar in distribution to BSR. Morphine, however, only causes significant increases in functional activity in the olfactory tubercle. Further, only in this brain site did the combination of BSR plus morphine or cocaine cause increases in functional activity over that of stimulation alone. These findings suggest that the olfactory tubercle plays a major role in the pharmacological actions of both the psychomotor stimulants and the opioids as well the rewarding effects of electrical stimulation of the brain.
Topics: Animals; Brain; Cocaine; Morphine; Motivation; Psychotropic Drugs; Rats; Receptors, Dopamine; Receptors, Opioid; Reinforcement, Psychology; Substance Withdrawal Syndrome; Substance-Related Disorders
PubMed: 1311122
DOI: No ID Found -
Journal of Anatomy Apr 1953
Topics: Animals; Brain; Histological Techniques; Humans; Olfactory Tubercle; Piriform Cortex; Porpoises
PubMed: 13044722
DOI: No ID Found -
Proceedings of the National Academy of... Apr 1969Removal of one olfactory bulb causes marked changes in the norepinephrine contents of several brain regions. The brainstem catecholamine level is higher on the side of...
Removal of one olfactory bulb causes marked changes in the norepinephrine contents of several brain regions. The brainstem catecholamine level is higher on the side of the lesion than on the control side, whereas telencephalic norepinephrine is lower ipsilateral to the lesion. The apparent decline in telencephalic norepinephrine is associated with a parallel decrease in the ability of this region to take up and retain (3)H-norepinephrine injected into the lateral cerebral ventricle. Within the ipsilateral olfactory tubercle, there is also a significant decrease in the activity of the enzyme phenylethanolamine-N-methyl transferase, which catalyzes the conversion of norepinephrine to epinephrine. The results of this study suggest that measurement of changes in the uptake of (3)H-norepinephrine injected into the cerebral ventricle can be used as a technique for mapping central adrenergic pathways.
Topics: Animals; Brain; Brain Chemistry; Female; Limbic System; Norepinephrine; Phenethylamines; Rats; Telencephalon; Transferases; Tritium
PubMed: 5256405
DOI: 10.1073/pnas.62.4.1052 -
Annals of the New York Academy of... Jun 1999The concept of the ventral striatum was first put forth by Heimer and Wilson to describe the extension of basal ganglia elements into the olfactory tubercle. The ventral... (Review)
Review
The concept of the ventral striatum was first put forth by Heimer and Wilson to describe the extension of basal ganglia elements into the olfactory tubercle. The ventral striatum includes the conventional nucleus accumbens, which has been closely associated with reward and motivation. This paper uses the afferent connections to the ventral striatum to define this region in monkeys. Furthermore the shell and core subterritories are discussed with respect to their histochemistry and specific connections.
Topics: Animals; Basal Ganglia; Corpus Striatum; Motivation; Olfactory Pathways; Primates; Reward
PubMed: 10415641
DOI: 10.1111/j.1749-6632.1999.tb09259.x -
Neuroscience 2003Projection neurons in the ventral striatum, the accumbens nucleus and olfactory tubercle, were examined by combining the retrograde tracing method and...
Projection neurons in the ventral striatum, the accumbens nucleus and olfactory tubercle, were examined by combining the retrograde tracing method and immunocytochemistry with antibodies against C-terminals of the preprodynorphin (PPD), preproenkephalin (PPE), preprotachykinin A (PPTA) and preprotachykinin B (PPTB). When the retrograde tracer was injected into the ventral pallidum, about 60% and 40% of retrogradely labeled neurons in the accumbens nucleus were immunoreactive for PPD and PPE, respectively. In contrast, all accumbens nucleus neurons projecting to the ventral mesencephalic regions including the substantia nigra and ventral tegmental area were immunopositive for PPD but not for PPE. Although no olfactory tubercle neurons projected fibers to the mesencephalic regions, 60% and 40% of olfactory tubercle neurons projecting to the ventrolateral portion of the ventral pallidum were immunoreactive for PPD and PPE, respectively, as were the accumbens nucleus neurons. About 70% of accumbens nucleus and olfactory tubercle neurons projecting to the ventral pallidum and all accumbens nucleus neurons projecting to the ventral mesencephalic regions showed PPTA immunoreactivity. A small population (2-12%) of accumbens neurons projecting to the ventral pallidum and mesencephalic regions displayed immunoreactivity for PPTB. Compared with the dorsal striatopallidal projection neurons that were reported to mostly express PPE, it was characteristic of the ventral striatum that only the smaller population (about 40%) of ventral striatopallidal projection neurons expressed PPE. This suggests that the ventral striatopallidal projection system is less specialized than the dorsal striatopallidal system in terms of peptide production, or that the ventral pallidum should be compared with a combined region of the globus pallidus and entopeduncular nucleus in the dorsal system.
Topics: Animals; Basal Ganglia; Dynorphins; Enkephalins; Fluorescent Antibody Technique; Immunoenzyme Techniques; Immunohistochemistry; Male; Neural Pathways; Neurokinin B; Neurons; Nucleus Accumbens; Olfactory Pathways; Peptide Fragments; Protein Precursors; Rats; Rats, Wistar; Tachykinins
PubMed: 12895518
DOI: 10.1016/s0306-4522(03)00326-9 -
International Journal of Developmental... 1986Neurogenesis in the rat primary olfactory cortex was examined with [3H]thymidine autoradiography. The experimental animals were the offspring of pregnant females given...
Neurogenesis in the rat primary olfactory cortex was examined with [3H]thymidine autoradiography. The experimental animals were the offspring of pregnant females given an injection of [3H]thymidine on two consecutive gestation days. Nine groups of embryos were exposed to [3H]thymidine on E13-E14, E14-E15....E21-E22, respectively. On P60, the percentage of labeled cells and the proportion of cells originating during 24 hr periods were quantified at selected anatomical levels of the anterior and posterior piriform cortex, dorsal lateral peduncular cortex, and posterior two-thirds of the ventral agranular insular cortex. Throughout most of the primary olfactory cortex, deep cells are generated earlier than superficial cells: the 'inside-out' pattern. Neurons in the anterior (prepiriform) cortex are located lateral to the caudal anterior olfactory nucleus and olfactory tubercle, and are generated mainly between E14 and E18 in a caudal (older) to rostral (younger) neurogenetic gradient. Neurons in the posterior (periamygdaloid) cortex are located lateral to the caudal olfactory tubercle and amygdala, and are generated mainly between E14 and E17 simultaneously along the rostrocaudal plane. Superficial cells in the piriform cortex have some additional neurogenetic gradients; ventromedial cells forming transition zones with either the olfactory tubercle or amygdala originate earlier than cells located dorsally and laterally. In the posterior piriform cortex, younger neurons are located at middle dorsoventral levels while older neurons lie above and below. Neurons in the dorsolateral peduncular cortex originate between E14 and E20 in a caudal to rostral gradient of neurogenesis; caudal parts also have a lateral to medial neurogenetic gradient. The most lateral part of the dorsolateral peduncular cortex is unique and does not have the typical 'inside-out' cortical neurogenetic gradient. Neurons in the ventral agranular insular cortex (area 13) originate mainly between E15 and E17 in combined caudal to rostral and ventral to dorsal neurogenetic gradients. The neurogenetic gradients in the primary olfactory cortex, along with patterns of neurogenesis throughout the olfactory projection field are related to the termination patterns of afferents from the main olfactory bulb.
Topics: Animals; Autoradiography; Cell Differentiation; Central Nervous System; Cerebral Cortex; Embryonic and Fetal Development; Gestational Age; Olfactory Pathways; Rats; Rats, Inbred Strains; Thymidine
PubMed: 3455589
DOI: 10.1016/0736-5748(86)90063-8 -
The Laryngoscope Oct 1986Routine clinical assessment of the integrity of the olfactory pathway using olfactory evoked potentials remains an elusive goal. One important difficulty arises from the...
Routine clinical assessment of the integrity of the olfactory pathway using olfactory evoked potentials remains an elusive goal. One important difficulty arises from the uncertainty of the exact origin of the potentials: are they produced by olfactory or trigeminal elements? To resolve this problem, an animal model using the rat was developed. Amylacetate was used as an odorant stimulus, and potentials were measured and computer averaged after elimination of trigeminal and vomeronasal activity. A positive-negative wave was recorded from the olfactory bulb surface, and a negative wave often followed by a positive wave was recorded from the surface of the cerebral cortex. Measurements from the scalp surface gave comparable results. Lesioning experiments of the olfactory pathway indicate that the evoked potentials recorded at the vertex originate in the ventral forebrain, specifically in the prepyriform cortex, olfactory tubercle, and anterior olfactory nucleus.
Topics: Animals; Central Nervous System; Cerebral Cortex; Evoked Potentials; Frontal Lobe; Male; Models, Biological; Olfactory Bulb; Olfactory Pathways; Pentanols; Rats; Rats, Inbred Strains; Reaction Time
PubMed: 3762286
DOI: 10.1288/00005537-198610000-00011 -
The Journal of Comparative Neurology Feb 1984The development of the cytoarchitecture and axonal connections of the central olfactory system were studied in fetal and neonatal rats from E16. In contrast to...
The development of the cytoarchitecture and axonal connections of the central olfactory system were studied in fetal and neonatal rats from E16. In contrast to neocortical development, the olfactory cortex lacks a distinct cortical plate. In the piriform cortex and the olfactory tubercle the cellular laminae emerge simultaneously, while in the anterior olfactory nucleus, there are morphogenetic gradients from superficial to deep as well as from caudal to rostral which parallel the known cytogenetic gradients. Parallel morphogenetic and cytogenetic gradients are also present in the lateral to medial axis of the olfactory tubercle. The projection from the olfactory bulb and the associational projections from the piriform cortex begin to develop well before birth. At E17 fibers from the bulb are limited to the lateral olfactory tract (LOT) and the molecular layer just deep to it, and then spread out caudally, laterally, and medially away from the LOT. This sequence of innervation parallels and predicts the density of innervation in the adult: those areas which are innervated first (such as the piriform cortex deep to the LOT) ultimately receive the heaviest innervation; conversely, those areas which are innervated very late (such as the medial olfactory tubercle) receive the lightest projection. The intracortical projections from the anterior and posterior piriform cortex extend into layer I ipsilaterally by E20 and obtain their adult distribution by the middle of the first postnatal week. On the other hand, fibers from the anterior olfactory nucleus and the entorhinal area do not reach their full adult extent until the second postnatal week. Similarly, the crossed projection of the anterior piriform cortex to the contralateral posterior piriform cortex does not grow into layer I until this later time. The timing of fiber ingrowth showed no relation to the trajectory or eventual areal or laminar termination of fibers. As with the olfactory bulb projection, the timing may influence the density of termination. Centrifugal fibers to the bulb are demonstrable around the time of birth both by the retrograde transport of horseradish peroxidase (HRP) and by the anterograde transport of 3H-leucine. The arrival of additional fibers during the remainder of the first postnatal week parallels the known cytogenetic and morphogenetic gradients in the areas in which they arise. The projections of the olfactory cortex to the lateral hypothalamic area and the mediodorsal thalamic nucleus are evident before birth. This correlates with the early generation of the cells which give rise to these projections.
Topics: Aging; Animals; Axonal Transport; Axons; Central Nervous System; Cerebral Cortex; Female; Gestational Age; Horseradish Peroxidase; Leucine; Olfactory Bulb; Olfactory Pathways; Pregnancy; Rats; Rats, Inbred Strains
PubMed: 6200518
DOI: 10.1002/cne.902230204