Search Results
Results 601 - 650 of 1320
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Amos S - - 2001
Behavioral effects of the aqueous extract of Guiera senegalensis on the central nervous system of mice and rats were investigated. Spontaneous motor activity, pentobarbital sleeping time, amphetamine-stereotyped behavior, exploratory activity and performance on treadmills (rota-rod) were evaluated. The results revealed that the aqueous extract of G. senegalensis reduced spontaneous motor ...
Yang P - - 2001
Repeated administration of psychomotor stimulants produces an enduring and progressively enhanced behavioral response known as behavioral sensitization, which has been implicated as a model for psychiatric disorders such as mania, schizophrenia, and drug addiction. The objective of the study was to determine whether lithium chloride (LiCl), an anti-manic agent, is ...
Beinfeld M C - - 2001
OLETF (Otsuka Long-Evans Tokushima Fatty) lacking the CCK 1 (A) receptor have similar spontaneous activity and locomotor response (horizontal and vertical activity) in response to a single injection of cocaine as the wild type LETO (Long Evans Tokushima Otsuka) rats. In contrast, the OLETF rats display more stereotypy in response ...
Aleksidze N G - - 2001
Quantitative distribution of bioactive substances in the brain of aggressive rats was studied. The norepinephrine/serotonin ratio increased in the temporal and parietal lobes, hypothalamus, and hippocampus of killer rats. The open filed behavior of aggressive rats is characterized by a long latency period, low locomotor activity, and slow movements. Exposure ...
Feng P - - 2001
The immature brain is much more sensitive to abnormal experience, particularly sleep deprivation, drug exposure, and maternal separation. The critical time period during which features in the brain's susceptibility to such experience change, however, has not yet been determined. In previous studies on rats, we found that neonatal treatment with ...
Wigger A - - 2001
Recently, two Wistar rat lines, bred and selected for either high (HAB) or low (LAB) anxiety-related behavior on the elevated plus-maze, were described as a novel psychopathologic animal model. The behavioral and neuroendocrine responses to exposure to an emotional stressor were markedly enhanced in HAB rats compared with LAB rats, ...
Molina-Hernandez M - - 2001
1. Isolation-reared rats display fear-like behavior and depressive-like behavior in several behavioral tasks, suggesting that isolation rearing may model certain aspects of human psychopathologies. 2. After weaning (20 days old), male and female Wistar rats were isolation-reared during 20, 50 or 70 days. After that, they were tested in the ...
Molina-Hernández M - - 2001
In rats, some behavioral changes occurring during pregnancy related to the presence of progesterone may be analyzed in the forced swimming task (FST), which is designed to test the antidepressant profile of drugs. The present study was aimed to analyze in pregnant rats, in rats after delivery, or in rats ...
Desjardins D - - 2001
Different ratios of normal male rats and male rats in which limbic seizures had been induced by a single systemic injection of lithium and pilocarpine were housed in groups of six. The group ratios ranged along the continuum from all normal rats to all experimental rats. The average numbers of ...
Frye C A - - 2001
Progesterone (P) to the ventromedial hypothalamus (VMH) and the ventral tegmental area (VTA) of ovariectomized (OVX), estradiol benzoate (EB)-primed rats and hamsters produces female sexual behavior similar to that seen in proestrous, receptive rodents. Because P's 5alpha-reduced metabolites can have facilitative effects on female sexual receptivity through actions at GABA(A)/benzodiazepine ...
Gerak L R - - 2001
Flunitrazepam was evaluated in several procedures that have been used extensively to study the behavioral effects and abuse potential of positive GABA(A) modulators. One group of monkeys (n=3) responded to receive injections of methohexital or saline (i.v.) while other groups (n=2-4/group) discriminated vehicle from either pentobarbital or triazolam. Other monkeys ...
Kamimura E - - 2001
PURPOSE: In a strain of the Long-Evans Cinnamon (LEC) rats, we found spontaneously hyperactive animals designated as "wiggling," and established a congenic wiggling (Wig) rat by transferring the gene from the LEC to the Wistar King-Aptekman/Hokkaido (WKAH) strain. We evaluated the feasibility of the Wig rat for an animal model ...
Jenkins W J - - 2001
Female rats engage in a series of approach and avoidance behaviors (pacing behavior) directed at the male in order to achieve a preferred rate of intromissions that make pregnancy more likely to occur with insemination. The striatum and nucleus accumbens have been implicated in the modulation of pacing behavior. It ...
Kolpakov V G - - 2001
The physiological actions of the gene controlling the predisposition to stereotypic hyperkinesia in the form of pendulum-like movements (PM) and, probably, a form of spontaneous nystagmus in rats with albinism are manifest as a number of behavioral characteristics (total motor activity, emotionality, startle reflex intensity, sensitivity to serotonin 5-HT2 receptors ...
Topczewska-Bruns J - - 2001
In addition to the changes in various biochemical parameters chronic renal insufficiency (CRI) leads to progressive behavioral disturbances both in humans and rats. To further characterize these changes, the present study aimed to investigate locomotor, exploratory and emotional activity of rats with experimental CRI. Our experiments with the open field ...
Blanchard D C - - 2001
The natural defensive behaviors of laboratory mice have been evaluated in both seminatural and highly structured situations; and characterized in terms of eliciting stimuli, response to pharmacological agents, behavior patterns, and outcome or effect on the social and physical environment. The defense patterns of laboratory mice and rats are generally ...
Carr J A.R. - - 2001
Rats were trained on an interval time-place task. Food was intermittently available on each of four levers for 4 min in a 16-min session. After baseline training the rats received 'open hopper' sessions in which food was available on all levers for all of the 16-min sessions. Despite the absence ...
Ohl F - - 2001
Emotionality is thought to be multidimensional, with "anxiety" representing one dimension. Dissecting emotional dimensions in animal models is an essential prerequisite for investigating the neurobiological mechanisms that underlie anxiety. The authors used factor analysis to investigate emotional dimensions in normal rats and rats bred for either high or low anxiety-related ...
Fusani L - - 2001
The courtship behavior of the male ring dove (Streptopelia risoria) combines aggressive displays (chasing, bowing) and nest-oriented displays (nest soliciting). Aggressive displays depend on circulating testosterone, whereas nest soliciting is estrogen-dependent and appears to depend on the aromatization of androgen into estrogen within the brain. The present work tested the ...
Sallés J - - 2001
RATIONALE: One of the major pathways for neurotransmitter signaling involves phosphoinositide-specific and G-protein-dependent phospholipase C-beta (PLC-beta), which stimulates the formation of inositol 1,4,5-trisphosphate and diacylglycerol. Serotonergic and muscarinic-cholinergic signals in the brain are largely mediated through the hydrolysis of phosphoinositides by PLC. OBJECTIVES: The aim of the experiments reported here ...
Sato J - - 2001
We investigated whether lowering barometric pressure by 20 mmHg (LP) aggravates the guarding behavior suggestive of spontaneous pain following sciatic nerve chronic constriction injury (CCI) in rats. Systemic blood pressure (BP) and heart rate (HR) of unrestrained rats were recorded telemetrically during LP both before and after the CCI surgery. ...
Cho A K - - 2001
Although the behavioral consequences of methamphetamine (METH) abuse have been extensively documented, a more precise and thorough understanding of underlying neurobiological mechanisms still requires the use of animal models. To study these biochemical processes in experimental animals requires consideration for the broad range of human METH abuse patterns and the ...
Ryu J S - - 2001
Endothelin-1 (ET-1), a novel and potent vasoconstrictor in blood vessel, is known to have some functions in the rat central nervous system (CNS). In order to investigate the central functions of ET-1, ET-1 was administered to the periaqueductal gray area (PAG) of anesthetized rats to induce barrel rolling and increase ...
Ben-Hur T - - 2001
Herpes simplex virus type 1 (HSV-1) encephalitis may present with fever and behavioral changes, to the extent of a psychotic state and psychomotor agitation. We developed a clinically relevant experimental model of HSV-1 encephalitis and investigated host brain responses associated with its clinical signs and whether these responses depend on ...
Lessenich A - - 2001
Abnormal circling behavior in rodents is usually attributed to vestibular dysfunction. In rats, all circling mutants described previously have inner ear defects resulting in auditory and vestibular dysfunctions. Here, we describe a new mutant rat with abnormal spontaneous circling behavior but normal auditory and vestibular functions. The new circling mutant ...
Paré W P WP Veterans Affairs Medical Center, Perry Point, MD, USA. - - 2000
The assumption was made that investigatory behaviors (i.e., ano-genital and general body sniffing) of a female conspecific by a mature male rat, has positive hedonic characteristics. Because reduced interest in pleasurable events (i.e., anhedonia) is diagnostically related to depressive behavior, the hypothesis was advanced that less investigatory behavior would be ...
Kantor S - - 2000
The Fawn-Hooded (FH) rat strain, with well-documented changes in their serotonergic and noradrenergic systems, is a putative genetic model for some neuropsychiatric disorders like depression, alcohol abuse, and anxiety. Because social phobia frequently occurs in combination with these disorders and there are no social anxiety-related data in FH rats in ...
Oxley G - - 2000
The present study was designed to determine whether the medial preoptic area (MPOA) and the amygdala (AMYG) are involved in the expression of "maternal" behavior in juvenile rats as they are in the adult. Juveniles show many behaviors that are similar to the maternal behaviors shown by the postpartum female ...
Datta S - - 2000
The aim of this study was to develop a sleep-wake recording system for rats that would yield results more comparable to those obtained from cats than those that are usually reported. For 18 male Sprague-Dawley rats, the authors combined measures of cortical and hippocampal electroencephalogram (EEG) and neck muscle electromyogram ...
Yamamoto Y - - 2000
Cholecystokinin (CCK) may have a role in the mediation of human panic disorder and anxiogenic (anxiolytic)-like activity in an animal model of anxiety. Otsuka Long Evans Tokushima Fatty (OLETF) rats lacked CCK A receptors (CCKAR) because of a genetic abnormality. In order to elucidate the involvement of CCKAR in the ...
Gonzales G F - - 2000
Metoclopramide is an antidopaminergic drug that binds D2 receptor at the central nervous system and peripheral levels. Recent studies have demonstrated the presence of a sexually dimorphic nucleus in the anterior hypothalamus of rats and humans. The sexual differentiation of brain and its expression on sexual behavior is directed by ...
Apelqvist G - - 2000
Chronic hepatic encephalopathy (HE) is a neuropsychiatric syndrome that arises in liver-impaired subjects. Patients with HE display various neuropsychiatric symptoms including affective disturbances and may therefore likely receive treatment with novel thymoleptics like citalopram (CIT). The simultaneous pharmacokinetic and pharmacodynamic outcome of the commonly used serotonin-selective thymoleptic drugs in liver-impaired ...
Wallace K J - - 2000
Four experiments tested whether an odor from a rat predator can unconditionally elicit a fear response in rats. In a large chamber, rats displayed fear-related behaviors to trimethylthiazoline (TMT, a volatile compound isolated from fox feces), including avoidance and immobility, while showing less exploratory behavior. In a smaller chamber, TMT ...
Iwasaki S - - 2000
Effects of maternal separation on feeding behavior, particularly on rebound hyperphagia, in adult rats were examined. Time-restricted scheduled feeding (2 h per day for 6 days), was given at the age of 3, 6, 9 or 12 weeks in rats that were maternal separated from postnatal days (PD) 1-21 and ...
Pisula W - - 2000
Roman high- and low-avoidance (RHA/Verh and RLA/Verh) rats differ in their emotionality profiles. As emotional processes are considered to play an important role in exploratory behavior, differences between the Roman sublines in responding to a novel environment can be anticipated. The present study provides a quantitative (based on the frequency ...
Kolaeva S G - - 2000
The effects of kyotorphin (KTP), a dipeptide (L-Tyr-L-Arg), on the level of sensory attention to stimuli of different modalities in rats and the exploratory behavior in goldfish were investigated. In both cases KTP was found to suppress the exploratory activity. When 5-HTP, a precursor of serotonin synthesis, is activated the ...
Petrov E S - - 2000
Newborn rat pups tested before suckling experience attached to and ingested milk from the surrogate nipple. Time attached to the nipple and amount of milk ingested depended on the schedule of milk infusion through the nipple. More frequent milk infusions resulted in more frequent disengagements from the nipple during the ...
Ribeiro A M - - 2000
The inhibition of excitatory mechanisms by components of low molecular weight, isolated from spiders and solitary wasps, such as, the acyl-polyamines, has demonstrated, on the one hand, neuroprotection potential, and on the other hand, it is well known that some arthropod venom components have convulsant activity. While many sophisticated experiments ...
Neuringer A - - 2000
Two pairs of experiments enabled students to compare their own operant behaviors with those of rats. The students played computer games for points, and the rats pressed levers for food. The first pair of experiments showed that, under concurrent schedules of reinforcement, relative frequencies of choices between two alternatives increased ...
Prat G - - 2000
We studied the synergistic effects of pergolide and bromocriptine with caffeine on turning behavior in 6-OHDA denervated rats. Both pergolide and bromocriptine were synergistic with caffeine, and prevented tolerance to caffeine-induced turning. When caffeine was removed, tolerance to bromocriptine effects was observed for 1 day only, while no tolerance was ...
Bacher L F - - 2000
The present experiment investigated the relationship between motor activity and oral grasping of an artificial nipple in newborn rats. Pups orally grasped the artificial nipple, and they performed more and longer oral grasps in the latter portion of the nipple presentation. Motor activity was cyclical, and this cyclicity was evident ...
Weidenbach A - - 2000
Ochratoxin A (OTA) a naturally occuring mycotoxin is nephrotoxic, hepatotoxic, teratogenic, embryotoxic, genotoxic, cancerogenic and immunosuppressive. Focussing on the immunemodulating effects, we found that OTA induces cytokine release from the isolated and bloodfree perfused rat liver. In the present study, we have characterized the liberation of tumor necrosis factor alpha ...
Edwards E - - 2000
The induction of learned helpless (LH) behavior in rats is a widely used model of unipolar depression. Recent studies have linked depression with hypertension and insulin resistance as observed in obesity, but the propensity of these disorders to manifest depression has not been reported. In this study, the LH behavioral ...
Nowak K L - - 2000
This study examined novelty-seeking behavior in rat populations selectively bred for high and low alcohol-drinking behavior. In Experiment 1, and "odor-enhanced" novel environment produced greater behavioral activation in P compared to NP rats. In Experiment 2, the activity of high alcohol-drinking P and HAD rats was enhanced to a greater ...
Popova N K - - 2000
The magnitudes of startle reactions, consisting of shuddering in response to acoustic signals, were studied in rats selected for predisposition to different types of defensive behavior-rats with and without passive defensive freezing reactions (catalepsy), and Norway rats selected for a lack of defensive aggression to humans or for high levels ...
Cai X - - 2000
The H-Tx rat is a genetic model of hydrocephalus for which thereis a poor understanding of the mode of inheritance. Previous studies suggested a polygenicmode of inheritance but the breeding data to supportthis hypothesis have not been reported. In an attempt to clarify the hereditary mode we have analyzed the ...
Nuñez J L - - 2000
There is recent evidence that cryoanesthesia, commonly used during neonatal hormone manipulations (e.g., gonadectomy), has deleterious effects on the morphology of the splenium of the corpus callosum and primary visual cortex in adult rats of both sexes. (Nuñez and Juraska, 1998; Nuñez, Kim, and Juraska, 1998). In the present study, ...
Ahmed S H - - 2000
The transition from stable to escalated levels of cocaine self-administration has been shown to depend upon drug availability. The generality of this phenomenon is assessed here by studying the effects of availability on heroin self-administration. Two groups of rats were trained on a 1-h continuous schedule of self-administration, after which, ...
Sheehan T P - - 2000
Evidence indicates there is a neural system that inhibits maternal behavior in virgin rats. It has been suggested that pregnancy hormones promote the onset of maternal behavior by reducing the behavioral influence of this system. The authors used c-Fos immunocytochemistry to identify brain regions more activated by pup exposure in ...
Thaw A K - - 2000
The behavioral taste responses of developmentally NaCl-restricted rats were examined with a brief-exposure taste test. Neurophysiological and morphological alterations have been reported in rats whose dietary sodium is restricted during pre- and postnatal development, yet there exists little data discerning their behavioral response to tastants. Control and developmentally NaCl-restricted rats ...
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