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P Kabai

Publications and source records attributed to P Kabai.

18 recordsLinked to original sources

Changes in binding to muscarinic and nicotinic cholinergic receptors in the chick telencephalon, following passive avoidance learning.

Changes in nicotinic and muscarinic cholinergic receptors 30 min after one-trial passive avoidance training were studied in day-old chicks (Gallus domesticus), by quantitative receptor autoradiography. [3H]-alpha-bungarotoxin (alpha-BgT) and [3H]-quinuclidinyl benzilate (QNB) were used to monitor changes in 15 forebrain regions for nicotinic and muscarinic receptors, respectively. A significant increase occurred bilaterally in the quantity of bound alpha-BgT in the lobus parolfactorius, while the amount of bound QNB decreased significantly, and bilaterally, in the hippocampus, hyperstriatum ventrale, lobus parolfactorius and posterolateral telencephalon, pars dorsalis. The data support an involvement of cholinergic receptor types in the neural mechanisms underlying passive avoidance learning.

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Methamphetamine-induced stereotypies in newly-hatched decerebrated domestic chicks.

Metamphetamine in high dose has been reported to induce stereotypic behavior of abnormal form in the pigeon and domestic chick. A number of reports suggested that the target of metamphetamine was the paleostriatal complex, the highest motor center of the avian brain. The present study tested this hypothesis by treating newly-hatched domestic chicks with high dose of metamphetamine (10 mg/kg b.w.) after complete decerebration or sham operation. Stereotypic mandibulations were observed both in sham-operated and in decerebrated birds in similar form following methamphetamine treatment. The results suggested that brainstem pattern generators remain responsive to dopaminergic stimuli in the absence of the main telencephalic (striatal) targets.

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Analysis of the mesotelencephalic dopamine system by quantitative-trait locus introgression.

One of the significant factors that affect brain dopamine function is the activity of tyrosine hydroxylase (TH), the first and rate-limiting enzyme in catecholamine biosynthesis. For the analysis of the genetically determined role of dopamine function and TH in behavior and in the regulatory mechanisms of the mesotelencephalic dopamine system we devised a novel genetic strategy (Vadasz; Mouse Genome 88:16-18; 1990). We hypothesized that phenotypic introgression and recombinant fixation could ensure the transfer of Quantitative Trait Loci (QTL) from one strain onto the genetic background of another strain, and new, genetically very similar quasi-congenic strains could be created that would carry individual QTLs, or QTLs in various combinations. Here we summarize the construction of the first set of QTL Introgression strains, and present evidence that QTLs that are responsible for the continuous variation of mesencephalic tyrosine hydroxylase activity (TH/MES), have been transferred onto the C57BL/6By (B6) strain background from BALB/cJ (C) and CXBI (I) donor strains with high and low TH/MES, respectively. The QTL transfer was carried out in two directions by repeated backcross-intercross cycles with concomitant selection for the extreme high and low expressions of TH/MES in replicates, resulting in four QTL Introgression lines. Analysis of regional brain TH activities in the course of the QTL introgression indicated that (a) TH activity in B6.I lines showed quite limited heritability, (b) TH/MES was not highly correlated with striatal TH, and (c) the control of hypothalamic and olfactory tubercle TH activities was largely independent from that of TH/MES. Examination of the open-field (OF) behavior data demonstrated that TH activity did not correlate significantly with OF behavior. After 5 backcross-intercross cycles, TH/MES in each replicate line was still significantly different from that of the B6 background strain. A genomewide scanning of microsatellite markers in the QTL introgression lines demonstrated that about 96% of the markers were of background (B6) type. These results indicate the successful transfer of TH/MES QTLs. After the QTL transfer phase of the experiment altogether more than 100 new RQI strains were initiated in the QTL Introgression lines by strict brother x sister mating. After fixing the introgressed QTLs, ten of the inbred RQI strains were tested for TH/MES. The results showed that in one of the new RQI strains TH/MES was restored to a level that is characteristic to the C donor strain, while TH/MES values in some other strains were between those of the background and donor strains, confirming our hypothesis that phenotypic introgression and recombinant fixation can ensure a virtually complete transfer of QTLs. We conclude from this study that complex, continuously distributed neural traits can successfully be subjected to QTL introgression, and the results raise the possibility that the RQI method can be efficiently applied for gene mapping of complex neural and behavioral traits even if their phenotypic expression is sensitive to confounding developmental and environmental variations, genetic interactions, and genotype-environment interactions.

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Efferent connections of the domestic chick archistriatum: a phaseolus lectin anterograde tracing study.

The archistriatum of the domestic chick has been implicated in both fear behaviour and learning. However, relatively little is known about its organisation. The efferent connections of discrete anatomical regions of the chick archistriatum were therefore investigated by iontophoresis of the anterograde tracer Phaseolus vulgaris leucoagglutinin into its anterior, dorsal intermediate, ventral intermediate, medial, and posterior parts. The results of this study suggest that the chick archistriatum can be divided into two basic divisions according to whether they project to the following limbic structures: the hippocampal formation, septal areas, lobus parolfactorius, nucleus accumbens, ventral paleostriatum, and dorsomedial thalamus. The limbic archistriatum includes the posterior archistriatum and extends rostrally through the ventral intermediate archistriatum into the anterior archistriatum. The non-limbic archistriatum comprises the dorsal intermediate and medial archistriatum and largely gives rise to specific sensory, somatosensory, and motor telencephalofugal efferents. There may not be distinct borders between these two divisions of the chick archistriatum.

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Unconditional discrimination as a paradigm for investigating visual processing in the avian brainstem.

Visual discrimination between colors and patterns was studied in telencephalectomized chicks of Japanese quail lines that were artificially selected for early approach preferences for particular colors and patterns. Since these preferences are not conditional on prior learning, they provide an effective experimental paradigm to study visual discrimination without reliance on acquired stimulus discrimination. The data indicate that the quail's brainstem-thalamus complex is sufficient for relatively fine discriminations between various colors and achromatic patterns.

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The involvement of dopamine in the striatum in passive avoidance training in the chick.

Quantitative receptor autoradiography was used to investigate the distribution of binding of [3H]SCH 23390 to dopamine (D1) and [3H]spiroperone to D2 receptors in regions of the forebrain of the one-day-old domestic chick (Gallus domesticus). High levels of specific binding of the D1 and D2 ligands were found in the striatal regions (paleostriatum augmentatum and lobus parolfactorius) of the one-day-old chick, as reported previously in the pigeon, turtle and rat, whilst binding levels were considerably lower in the pallidum (paleostriatum primitivum), hippocampus and hyperstriatum ventrale. The proportions of D1 and D2 receptor binding in the chick were relatively similar in the striatum and pallidum, apart from the paleostriatum augmentatum, where D2 receptors outnumber those of D1 by a factor of two. Binding of the D1 and D2 ligands to forebrain regions was also investigated 30 min after one-trial passive avoidance training of one-day-old chicks in which the aversive stimulus was a bead coated with a bitter tasting substance, methyl anthranilate. These experiments demonstrated a large and highly significant bilateral increase (compared to control birds) in binding to D1 (but not D2) receptors in the lobus parolfactorius. In this striatal region, equivalent to the caudate-putamen of mammals, previous studies have shown that synaptic and dendritic alterations occur following avoidance training. It is concluded that alterations in dopamine binding may be involved in processes that result in modification of the pecking response in chicks after avoidance training.

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Effects of diencephalic lesions on approach responses and color preferences in quail.

The effects of stereotaxic radio-frequency lesions on artificially selected approach responses and artificially selected or imprinted red or blue preferences were studied in Japanese quail chicks. No effects were found from lesions in anterior preoptic or pretectal areas and only slight attenuation of red preferences by lesions in nucleus rotundus, opticus principalis thalami and geniculatus lateralis pars ventralis. Extensive lesions in medial diencephalic and bordering areas of telencephalon, ansa lenticularis, lateral and medial forebrain bundle diminished approach tendencies and greatly attenuated the genetically influenced red preferences. Medial diencephalic lesions confined to the dorsomedial thalamic complex and lateral hypothalamus left approach tendencies intact but similarly attenuated only red preferences. Imprinted red or blue preferences of a highly imprintable quail line were also attenuated; red preference strongly, blue preference moderately. The data indicate differential diencephalic mediation of the quail's genetically distinct color preferences and suggest diverse subtelencephalic channels for mediation of approach responses and stimulus preferences. The results also suggest common neural mediation of genetically determined and acquired stimulus preferences.

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Effects of bilateral hemispherectomy on genetically variable stimulus preferences and imprinting in quail chicks.

Bilateral ablation of the telencephalon on the 1st posthatch day prevented learning from imprinting to colored stimuli in Japanese quail chicks C. coturnix japonica, but it spared their artificially selected approach preferences for particular colors and patterns. Post-imprinting decerebration on the 3rd posthatch day erased the imprinted memory, but did not revert the chicks' approach choices to the colors of their genetically distinct initial preferences. The genetically determined and the acquired preferences were both lost in the latter birds, regardless whether they were imprinted to the initially preferred or the initially nonpreferred stimuli before decerebration. Discussion focuses on implications of the data for modeling specific interactions between and the interrelated neural representation of genetic and environmental influences in early behavioral development.

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Persistence of approach response after decerebration in newly hatched quail chicks.

The role of telencephalon in controlling the unconditional approach response was studied in newly hatched Japanese quail chicks by lesions. Approach to flickering light and a moving object were not diminished by ablation of various telencephalic areas, ranging from caudal forebrain lesions to complete bilateral hemispherectomy. Open field activity and tonic immobility were likewise unaffected. Results indicated that the neural mediation of unconditional sensory-motor components of imprinting is anatomically separated from the telencephalon, where recognition memory is thought to be formed.

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Subtelencephalic visual discrimination in selected lines of Japanese quail.

We studied visual discrimination capabilities of the avian brain stem in genetic lines of Japanese quail artificially selected for unconditional approach preference for blue, red or an achromatic pattern stimulus. Complete telencephalectomy did not abolish approach behavior and visual discrimination. Our data indicate that visual feature extraction and motor coordination related to early approach preferences in birds may be mediated by brain stem and thalamic circuitries which do not require input from higher level visual and motor regions.

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Neural correlates of genetically determined and acquired color preferences in quail chicks.

The uptake of tritiated 2-deoxyglucose (2-DG) was examined in brains of artificially selected and unselected control quail, in relation to genetically and environmentally variable early approach preferences of a colored stimulus. The data indicated high labeling in the tectofugal and low labeling in the thalamofugal projection systems in birds exhibiting preference for the light wavelength characteristics of the stimulus in independently tested choice situations. The differential labeling was observed regardless whether the stimulus preference was genetic or environmental in origin (i.e. whether it was exhibited by artificially selected and experientially naive or by unselected and imprinted control chicks). Chicks responding to the stimulus after prior imprinting experiences also exhibited high labeling in the intermediate medial portions of the neostriatum and hyperstriatum ventrale.

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Perinatal anti-androgen treatment and genotype affect the mesotelencephalic dopamine system and behavior in mice.

Sex and strain differences in tyrosine hydroxylase activity (TH) of brain dopamine systems have been reported for mice. To investigate if there might be a causal relationship between perinatal androgen secretion and regional mesotelencephalic TH activity, BALB/cJ and C57BL/6ByJ male mice were treated perinatally with cyproterone, a steroidal anti-androgen (or vehicle), and orchiectomized at 1 month of age. Two-way analysis of variance indicated significant treatment and strain effects in the mesencephalon and tuber olfactorium: perinatal cyproterone treatment lowered TH activity, and BALB/cJ had higher regional TH activities than those of C57BL/6ByJ. The most prominent behavioral effects of cyproterone treatment were found in the expression of scratching, which was considerably increased in both strains. Possible implications of these results are discussed.

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Correlation of sexual behaviour and ovarian processes in the paradise fish, Macropodus opercularis.

Changes in ovarian development were described during successive phases of reproductive behaviour defined from an ethological approach in paradise fish, Macropodus opercularis. We found this perannial breeder fish to show typical induced ovulation pattern and during the synchronization process each behavioural phase (or maintenance condition) can be characterized by a dominant cell type. Our preliminary results suggest, that M. opercularis is an excellant model animal for quantitative studies of the effects of behavioural and endocrine factors in reproductive synchronization.

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