Biomedical subjects

T Skrebuhhova

Publications and source records attributed to T Skrebuhhova.

8 recordsLinked to original sources

PubMed1999

Modulatory role of 5-HT3 receptors in mediation of apomorphine-induced aggressive behaviour in male rats.

We have studied the effects of serotonin (5-HT) 5-HT3 receptor agonists 1-phenylbiguanide (1-PBG) and 1-(m-chlorophenyl)biguanide (mCPBG), and antagonists 3-tropanyl-3,5-dichlorobenzoate (MDL-72222) and tropisetron (3-tropanyl-indole-3-carboxylate HCl; ICS-205930) on apomorphine-induced aggressive behaviour in normal or DSP-4 [N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride] pre-treated male Wistar rats. DSP-4 (50 mg/kg) pre-treatment significantly accelerated the development of apomorphine-induced aggressive behaviour. mCPBG (1.0 and 10 mg/kg) did not modify the aggressiveness, but 1-PBG (3.0 and 30 mg/kg) attenuated the aggressiveness in normal but not DSP-4 pre-treated rats. MDL-72222 (0.4 and 4.0 mg/kg) attenuated the aggressive behaviour in normal rats, tropisetron (0.3 mg/kg) had an antiaggressive effect only by citalopram (10 mg/kg) challenge. MDL-72222 and tropisetron were ineffective in DSP-4 pre-treated rats. In conclusion, our results indicate that the 5-HT3 receptors modulate the apomorphine-induced aggressive behaviour and the 5-HT3 receptor antagonists have moderate antiaggressive effect in this test.

Aggression↗

PubMed1999

Effects of anxiogenic drugs in rat forced swimming test.

The effect of antidepressants and anxiogenics in the forced swimming (Porsolt') test was investigated in rats. On the second day of an experiment, desipramine (10 mg/kg), pentylenetetrazole (20 mg/kg), picrotoxin (2.5 mg/kg), and clonidine (1.0 mg/kg) shortened while buspirone (1.0 mg/kg), yohimbine (2.5 mg/kg), DMCM (1.0 mg/kg), and Ro-15-4513 (1.0 mg/kg) prolonged the time of immobility or behavioral despair; fluoxetine (10 and 20 mg/kg), citalopram (10 mg/kg), and flumazenil (10 mg/kg) were ineffective. While clonidine, given in a subeffective dose (0.1 mg/kg), augmented the effect of desipramine (10 mg/kg), buspirone (1.0 mg/kg) had an opposite effect. The picrotoxin (2.5 mg/kg) challenge prominently shortened the time of immobility after desipramine (10 mg/kg) or citalopram (10 mg/kg) treatment. In conclusion, our results indicate that pharmacologically enhanced anxiety interacts with the effects of acute drug treatment in the forced swimming test.

Animals↗

PubMed1999

Apomorphine-induced upregulation of serotonin 5-HT2A receptors in male rats is independent from development of aggressive behaviour.

The [3H]ketanserin binding characteristics in the apomorphine-induced aggressive and nonaggressive adult male Wistar rats were studied. Repeated apomorphine (0.5 mg/kg, once daily) treatment gradually induced aggressive behaviour in sixteen animals from twenty. Thereafter the animals were retrospectively divided into apomorphine-induced aggressive and nonaggressive group. The maximal number of the [3H]ketanserin binding sites was increased in the apomorphine-treated animals in the frontal (233.9+/-26.5, 364.6+/-31.7, and 367.0+/-34.8 fmol/mg protein for the vehicle, apomorphine-nonaggressive, and apomorphine-aggressive group, respectively) and cerebral cortex (164.2+/-6.7, 289.7+/-29.3, and 249.0+/-15.4 fmol/mg protein for the vehicle, apomorphine-nonaggressive, and apomorphine-aggressive group, respectively). In conclusion, our experiments demonstrate that repeated apomorphine treatment upregulates the maximal number of the 5-HT2A receptors in rat frontal and cerebral cortex as measured by [3H]ketanserin binding and this phenomenon is independent from the development of aggressive behaviour.

Aggression↗

PubMed1999

[3H]-ketanserin binding and elevated plus-maze behavior after chronic antidepressant treatment in DSP-4 and P-CPA pretreated rats: evidence for partial involvement of 5-HT2A receptors.

[3H]-Ketanserin binding in rat neocortex (frontal and cerebral cortex) after 3-week treatment with desipramine (10 mg/kg) and citalopram (5 mg/kg) in vehicle-, DSP-4- (50 mg/kg) and p-CPA- (350 mg/kg before the beginning of experiments and once per week on the first and second week plus 100 mg/kg in the last week) pretreated rats was measured. The antidepressant activity of DSP-4 and p-CPA was evaluated indirectly using the elevated plus-maze test. Acute antidepressant treatment revealed an anxiogenic effect while chronic treatment elicited an anxiolytic effect. DSP-4 and p-CPA pretreatment elicited an antiexploratory effect that was not blocked by acute antidepressant treatment. After 3 weeks of antidepressant treatment, only desipramine + DSP-4 or p-CPA treatment revealed an antiexploratory effect. Three-week antidepressant treatment downregulated [3H]-ketanserin binding in the cerebral cortex. Citalopram treatment partially reversed p-CPA-induced downregulation of [3H]-ketanserin binding in rat whole neocortex. In conclusion, our experiments suggest that the 5-HT2A receptors in monoamine-impaired rats are involved in the mediation of antidepressant-induced behavioral phenomena, but chronic antidepressant treatment downregulates [3H]-ketanserin binding independently from the state of monoaminergic neurotransmission.

Animals↗

PubMed1998

Apomorphine-induced aggressiveness and [3H]citalopram binding after antidepressant treatment in rats.

The effects of acute and repeated administration of antidepressive drugs on apomorphine-induced aggressive behavior and [3H]citalopram binding were studied. In acute behavioral experiments with apomorphine pretreated (1.0 mg/kg, once daily) animals, desipramine (10 mg/kg) and clomipramine (10 mg/kg) enhanced, buspirone (2.5 and 5.0 mg/kg) completely blocked, but fluoxetine, amitriptyline, imipramine (10 mg/kg), and citalopram (10 and 20 mg/kg) had no effect on the intensity of aggressive behavior. Repeated concomitant apomorphine (1.0 mg/kg) and citalopram (10 mg/kg) administration reduced the affinity (Kd) of the 5-HT transporter binding sites in three brain regions. This finding was confirmed by an additional experiment as the effect of citalopram treatment. Repeated apomorphine (1.0 mg/kg) or apomorphine (1.0 mg/kg) plus desipramine (10 mg/kg) treatment had no unidirectional effect on Kd, the maximal number of apparent binding sties (Bmax) was unchanged in all experiments. Our study indicates that the 5-HT reuptake blockade has no major influence on the apomorphine-induced aggressive behavior, but the 5-HT1A receptor subtype may be involved in the mediation of the aggressive behavior in this paradigm.

Aggression↗

PubMed1998

The effect of antidepressants on rat aggressive behavior in the electric footshock and apomorphine-induced aggressiveness paradigms.

The effects of acute antidepressant treatment were studied in the electric footshock and apomorphine-induced aggressiveness paradigms and found to be ineffective in both experimental models. In the apomorphine-induced aggressiveness test, 100 mg/kg L-tryptophan challenge manifested the antiaggressive effect of 10 mg/kg fluoxetine (a selective serotonin reuptake inhibitor) treatment. Thus, concomitant L-tryptophan plus fluoxetine treatment decreased the intensity of aggressive postures and increased the time of latency before first attack. In conclusion, our study demonstrates the involvement of the serotoninergic neurotransmission in the neurobiology of aggressive behavior, but after acute treatment in normal rats, the antidepressants do not elicit antiaggressive effects.

Aggression↗

PubMed1997

Characterization of rat exploratory behavior using the exploration box test.

A method to measure various aspects of exploratory behavior was further characterized using standard pharmacological treatments known to induce anxiety, or anxiolysis, or locomotor activation. FG 7142, an anxiogenic beta-carboline, induced a dose-dependent reduction in the rat exploratory behavior. A single FG 7142 (20 mg/kg) treatment before behavioral testing had a carry-over effect on rats' behavioral performance on the two subsequent days. When FG 7142 (20 mg/kg) was administered during five consecutive days before behavioral testing, its anxiogenic-like effect first deepened, but waned off by the fifth session. Diazepam at the dose of 0.5 mg/kg had no effect of its own, but blocked the anxiogenic-like effect of FG 7142 (10 mg/kg) treatment. At a higher dose (1 mg/kg), diazepam treatment reduced exploratory behavior, but this effect was not carried over to the drug-free sessions on the subsequent day. Buspirone and gepirone (both 1 mg/kg), the 5-HT1A receptor agonists, had no effect. D-Amphetamine, a locomotion-enhancing drug which has anxiogenic-like properties in several tests of exploratory behavior, increased the activity of rats at the dose of 0.5 mg/kg, but at the dose of 1 mg/kg the only effect was a reduction in the number of rearings: this effect was not carried over to the subsequent retest. On the basis of the results described in this article and elsewhere, we suggest that this technique can be useful for separating a true anxiogenic drug from other compounds which influence exploratory activity.

Amphetamine↗

PubMedDate not supplied

Changes in [3H]citalopram binding in cerebral cortex after antidepressant treatment in monoamine-impaired rats.

The [3H]citalopram binding after three weeks vehicle, desipramine 10 mg/kg or citalopram 5 mg/kg treatment was studied in the cerebral cortex of normal, DSP-4-, and p-CPA-impaired rats. The DSP-4 50 mg/kg treatment decreased the affinity (Kd), but increased the maximal number of the apparent binding sites (Bmax) of the 5-hydroxytryptamine transporter (5-HTT). This effect was reversed by desipramine 10 mg/kg treatment. The p-CPA 350 mg/kg treatment decreased the Bmax value while the antidepressant treatment did not influence this parameter. In conclusion, our experiments demonstrate that the monoaminergic impairment induced by DSP-4 and p-CPA treatment evokes opposite changes in the 5-HTT binding characteristics and these changes are partially reversed by the chronic antidepressant treatment.

Animals↗