The Experts below are selected from a list of 54 Experts worldwide ranked by ideXlab platform
Werner J Schmidt - One of the best experts on this subject based on the ideXlab platform.
-
Catha Edulis Extract and its active principle cathinone induce ipsilateral rotation in unilaterally lesioned rats
Behavioural Pharmacology, 2006Co-Authors: Mehret Yerdaw Banjaw, Werner J SchmidtAbstract:Catha Edulis Extract, a natural psychostimulant, and its active component, S-( - )-cathinone, were evaluated for their rotational effects in unilaterally lesioned rats. In our earlier study, we demonstrated that commercially available S-( - )-cathinone, the active principle of C. Edulis Extract, reverses haloperidol-induced catalepsy. In the current study, we evaluated the effect of C. Edulis Extract or its active principle, cathinone, in 6-hydroxydopamine unilaterally lesioned rats. Evaluation of the rotational behaviour induced by this natural psychostimulant was made upon acute and repeated oral administration. The data show that C. Edulis Extract or S-( - )-cathinone induced ipsilateral rotation in 6-hydroxydopamine unilaterally lesioned rats. The ipsilateral rotation produced by commercially available S-(-)-cathinone was more marked than the response produced by oral administration of lyophilized C. Edulis Extract at the dose and periods specified. In addition, upon repeated administration, the effect was more pronounced (i.e. there was sensitization). In conclusion, the results demonstrate that the plant induces ipsilateral rotation, like its close relative amphetamine.
-
clozapine attenuates the locomotor sensitisation and the prepulse inhibition deficit induced by a repeated oral administration of Catha Edulis Extract and cathinone in rats
Behavioural Brain Research, 2005Co-Authors: Mehret Yerdaw Banjaw, Markus Fendt, Werner J SchmidtAbstract:Abstract Locomotor sensitisation and deficits in prepulse inhibition (PPI) induced by psychostimulants are two paradigms that have been widely studied as animal behavioural models of psychosis. Clozapine is one of the atypical antipsychotic agents which has been widely employed to reverse the aforementioned behavioural changes in these usual models. In this particular study, locomotor sensitisation and prepulse inhibition deficit were induced under the same context by intermittent oral administration of S -(−)-cathinone or Catha Edulis Extract in rats. The rats were then challenged by administration of the atypical antipsychotic drug, clozapine and were finally challenged with psychostimulants after 2-week of withdrawal. Locomotor activity and PPI were assessed and later analyses of the neurotransmitter levels were made. The results of this experiment show that repeated oral administration of cathinone or C. Edulis Extract enhanced locomotor and exploratory activity and lead to a gradual deficit in prepulse inhibition. This locomotor sensitisation and PPI deficit could be reversed by administration of clozapine. A challenge with psychostimulant on day 40 (i.e., after 2-week of withdrawal) resulted in a response similar to the initial exposure (day 1). Neurotransmitter level analyses showed a significant increase in the level of dopamine in the prefrontal cortex ( p p p C. Edulis Extract, or commercial cathinone, induces prepulse inhibition deficit and clozapine reverses both C. Edulis or cathinone-induced sensitised locomotion and prepulse inhibition deficit.
-
clozapine attenuates the locomotor sensitisation and the prepulse inhibition deficit induced by a repeated oral administration of Catha Edulis Extract and cathinone in rats
Behavioural Brain Research, 2005Co-Authors: Mehret Yerdaw Banjaw, Markus Fendt, Werner J SchmidtAbstract:Locomotor sensitisation and deficits in prepulse inhibition (PPI) induced by psychostimulants are two paradigms that have been widely studied as animal behavioural models of psychosis. Clozapine is one of the atypical antipsychotic agents which has been widely employed to reverse the aforementioned behavioural changes in these usual models. In this particular study, locomotor sensitisation and prepulse inhibition deficit were induced under the same context by intermittent oral administration of S-(-)-cathinone or Catha Edulis Extract in rats. The rats were then challenged by administration of the atypical antipsychotic drug, clozapine and were finally challenged with psychostimulants after 2-week of withdrawal. Locomotor activity and PPI were assessed and later analyses of the neurotransmitter levels were made. The results of this experiment show that repeated oral administration of cathinone or C. Edulis Extract enhanced locomotor and exploratory activity and lead to a gradual deficit in prepulse inhibition. This locomotor sensitisation and PPI deficit could be reversed by administration of clozapine. A challenge with psychostimulant on day 40 (i.e., after 2-week of withdrawal) resulted in a response similar to the initial exposure (day 1). Neurotransmitter level analyses showed a significant increase in the level of dopamine in the prefrontal cortex (p < 0.05). There was also a significant decrease in the level of 5-hydroxytryptamine (5-HT) in the nucleus accumbens (p < 0.05) and its metabolite, 5-hydroxyindole acetic acid (5-HIAA) in the prefrontal cortex (p < 0.01). In the remaining regions (anterior and posterior striatum), there were no significant changes. In conclusion, this is the first study to demonstrate that repeated administration of C. Edulis Extract, or commercial cathinone, induces prepulse inhibition deficit and clozapine reverses both C. Edulis or cathinone-induced sensitised locomotion and prepulse inhibition deficit.
Mehret Yerdaw Banjaw - One of the best experts on this subject based on the ideXlab platform.
-
Catha Edulis Extract and its active principle cathinone induce ipsilateral rotation in unilaterally lesioned rats
Behavioural Pharmacology, 2006Co-Authors: Mehret Yerdaw Banjaw, Werner J SchmidtAbstract:Catha Edulis Extract, a natural psychostimulant, and its active component, S-( - )-cathinone, were evaluated for their rotational effects in unilaterally lesioned rats. In our earlier study, we demonstrated that commercially available S-( - )-cathinone, the active principle of C. Edulis Extract, reverses haloperidol-induced catalepsy. In the current study, we evaluated the effect of C. Edulis Extract or its active principle, cathinone, in 6-hydroxydopamine unilaterally lesioned rats. Evaluation of the rotational behaviour induced by this natural psychostimulant was made upon acute and repeated oral administration. The data show that C. Edulis Extract or S-( - )-cathinone induced ipsilateral rotation in 6-hydroxydopamine unilaterally lesioned rats. The ipsilateral rotation produced by commercially available S-(-)-cathinone was more marked than the response produced by oral administration of lyophilized C. Edulis Extract at the dose and periods specified. In addition, upon repeated administration, the effect was more pronounced (i.e. there was sensitization). In conclusion, the results demonstrate that the plant induces ipsilateral rotation, like its close relative amphetamine.
-
clozapine attenuates the locomotor sensitisation and the prepulse inhibition deficit induced by a repeated oral administration of Catha Edulis Extract and cathinone in rats
Behavioural Brain Research, 2005Co-Authors: Mehret Yerdaw Banjaw, Markus Fendt, Werner J SchmidtAbstract:Abstract Locomotor sensitisation and deficits in prepulse inhibition (PPI) induced by psychostimulants are two paradigms that have been widely studied as animal behavioural models of psychosis. Clozapine is one of the atypical antipsychotic agents which has been widely employed to reverse the aforementioned behavioural changes in these usual models. In this particular study, locomotor sensitisation and prepulse inhibition deficit were induced under the same context by intermittent oral administration of S -(−)-cathinone or Catha Edulis Extract in rats. The rats were then challenged by administration of the atypical antipsychotic drug, clozapine and were finally challenged with psychostimulants after 2-week of withdrawal. Locomotor activity and PPI were assessed and later analyses of the neurotransmitter levels were made. The results of this experiment show that repeated oral administration of cathinone or C. Edulis Extract enhanced locomotor and exploratory activity and lead to a gradual deficit in prepulse inhibition. This locomotor sensitisation and PPI deficit could be reversed by administration of clozapine. A challenge with psychostimulant on day 40 (i.e., after 2-week of withdrawal) resulted in a response similar to the initial exposure (day 1). Neurotransmitter level analyses showed a significant increase in the level of dopamine in the prefrontal cortex ( p p p C. Edulis Extract, or commercial cathinone, induces prepulse inhibition deficit and clozapine reverses both C. Edulis or cathinone-induced sensitised locomotion and prepulse inhibition deficit.
-
clozapine attenuates the locomotor sensitisation and the prepulse inhibition deficit induced by a repeated oral administration of Catha Edulis Extract and cathinone in rats
Behavioural Brain Research, 2005Co-Authors: Mehret Yerdaw Banjaw, Markus Fendt, Werner J SchmidtAbstract:Locomotor sensitisation and deficits in prepulse inhibition (PPI) induced by psychostimulants are two paradigms that have been widely studied as animal behavioural models of psychosis. Clozapine is one of the atypical antipsychotic agents which has been widely employed to reverse the aforementioned behavioural changes in these usual models. In this particular study, locomotor sensitisation and prepulse inhibition deficit were induced under the same context by intermittent oral administration of S-(-)-cathinone or Catha Edulis Extract in rats. The rats were then challenged by administration of the atypical antipsychotic drug, clozapine and were finally challenged with psychostimulants after 2-week of withdrawal. Locomotor activity and PPI were assessed and later analyses of the neurotransmitter levels were made. The results of this experiment show that repeated oral administration of cathinone or C. Edulis Extract enhanced locomotor and exploratory activity and lead to a gradual deficit in prepulse inhibition. This locomotor sensitisation and PPI deficit could be reversed by administration of clozapine. A challenge with psychostimulant on day 40 (i.e., after 2-week of withdrawal) resulted in a response similar to the initial exposure (day 1). Neurotransmitter level analyses showed a significant increase in the level of dopamine in the prefrontal cortex (p < 0.05). There was also a significant decrease in the level of 5-hydroxytryptamine (5-HT) in the nucleus accumbens (p < 0.05) and its metabolite, 5-hydroxyindole acetic acid (5-HIAA) in the prefrontal cortex (p < 0.01). In the remaining regions (anterior and posterior striatum), there were no significant changes. In conclusion, this is the first study to demonstrate that repeated administration of C. Edulis Extract, or commercial cathinone, induces prepulse inhibition deficit and clozapine reverses both C. Edulis or cathinone-induced sensitised locomotion and prepulse inhibition deficit.
Albert W Nyongesa - One of the best experts on this subject based on the ideXlab platform.
-
effects of single daily khat Catha Edulis Extract on spatial learning and memory in cba mice
Behavioural Brain Research, 2008Co-Authors: Samuel Kimani, Albert W NyongesaAbstract:This study investigated the effects of fresh khat Extract on learning and memory in CBA mice. A total of 20 male CBA mice, weighing 20–30 g, 5–6 weeks old were administered intraperitoneally with a single daily dose of khat Extract for 5 days. The animals were divided into four groups, each comprising five animals. The first three groups were administered three doses (40, 120 and 360 mg/kg body weight) of khat Extract, respectively. The last group served as controls and was administered with 0.5 ml normal saline intraperitoneally. The animals were then subjected to Morris water maze (MWM) task performance. Moderate and high doses (120 and 360 mg/kg body weight) of khat Extract significantly impaired (P < 0.05) while low dose (40 mg/kg body weight) of khat Extract did not have a significant effect on CBA mice acquisition learning. The high dose of khat Extract significantly (P < 0.05) improved while moderate and low doses impaired accuracy for spatial memory of the platform location. This study has shown that khat Extract has selective effect on spatial learning and memory, with low dose having no effect on learning but impairing memory, whereas high dose impairs learning but improves memory.
-
in vitro study of the effects of khat Catha Edulis forsk Extract on isolated mouse interstitial cells
Journal of Ethnopharmacology, 2007Co-Authors: Albert W Nyongesa, D W Onyango, E O Wango, Nilesh Patel, H. OdongoAbstract:Abstract Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha Edulis) Extract (0.06 mg/ml, 0.6 mg/ml, 6 mg/ml, 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat Extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml, 0.6 mg/ml and 6 mg/ml) significantly stimulated (P
Markus Fendt - One of the best experts on this subject based on the ideXlab platform.
-
clozapine attenuates the locomotor sensitisation and the prepulse inhibition deficit induced by a repeated oral administration of Catha Edulis Extract and cathinone in rats
Behavioural Brain Research, 2005Co-Authors: Mehret Yerdaw Banjaw, Markus Fendt, Werner J SchmidtAbstract:Abstract Locomotor sensitisation and deficits in prepulse inhibition (PPI) induced by psychostimulants are two paradigms that have been widely studied as animal behavioural models of psychosis. Clozapine is one of the atypical antipsychotic agents which has been widely employed to reverse the aforementioned behavioural changes in these usual models. In this particular study, locomotor sensitisation and prepulse inhibition deficit were induced under the same context by intermittent oral administration of S -(−)-cathinone or Catha Edulis Extract in rats. The rats were then challenged by administration of the atypical antipsychotic drug, clozapine and were finally challenged with psychostimulants after 2-week of withdrawal. Locomotor activity and PPI were assessed and later analyses of the neurotransmitter levels were made. The results of this experiment show that repeated oral administration of cathinone or C. Edulis Extract enhanced locomotor and exploratory activity and lead to a gradual deficit in prepulse inhibition. This locomotor sensitisation and PPI deficit could be reversed by administration of clozapine. A challenge with psychostimulant on day 40 (i.e., after 2-week of withdrawal) resulted in a response similar to the initial exposure (day 1). Neurotransmitter level analyses showed a significant increase in the level of dopamine in the prefrontal cortex ( p p p C. Edulis Extract, or commercial cathinone, induces prepulse inhibition deficit and clozapine reverses both C. Edulis or cathinone-induced sensitised locomotion and prepulse inhibition deficit.
-
clozapine attenuates the locomotor sensitisation and the prepulse inhibition deficit induced by a repeated oral administration of Catha Edulis Extract and cathinone in rats
Behavioural Brain Research, 2005Co-Authors: Mehret Yerdaw Banjaw, Markus Fendt, Werner J SchmidtAbstract:Locomotor sensitisation and deficits in prepulse inhibition (PPI) induced by psychostimulants are two paradigms that have been widely studied as animal behavioural models of psychosis. Clozapine is one of the atypical antipsychotic agents which has been widely employed to reverse the aforementioned behavioural changes in these usual models. In this particular study, locomotor sensitisation and prepulse inhibition deficit were induced under the same context by intermittent oral administration of S-(-)-cathinone or Catha Edulis Extract in rats. The rats were then challenged by administration of the atypical antipsychotic drug, clozapine and were finally challenged with psychostimulants after 2-week of withdrawal. Locomotor activity and PPI were assessed and later analyses of the neurotransmitter levels were made. The results of this experiment show that repeated oral administration of cathinone or C. Edulis Extract enhanced locomotor and exploratory activity and lead to a gradual deficit in prepulse inhibition. This locomotor sensitisation and PPI deficit could be reversed by administration of clozapine. A challenge with psychostimulant on day 40 (i.e., after 2-week of withdrawal) resulted in a response similar to the initial exposure (day 1). Neurotransmitter level analyses showed a significant increase in the level of dopamine in the prefrontal cortex (p < 0.05). There was also a significant decrease in the level of 5-hydroxytryptamine (5-HT) in the nucleus accumbens (p < 0.05) and its metabolite, 5-hydroxyindole acetic acid (5-HIAA) in the prefrontal cortex (p < 0.01). In the remaining regions (anterior and posterior striatum), there were no significant changes. In conclusion, this is the first study to demonstrate that repeated administration of C. Edulis Extract, or commercial cathinone, induces prepulse inhibition deficit and clozapine reverses both C. Edulis or cathinone-induced sensitised locomotion and prepulse inhibition deficit.
Samuel Kimani - One of the best experts on this subject based on the ideXlab platform.
-
effects of single daily khat Catha Edulis Extract on spatial learning and memory in cba mice
Behavioural Brain Research, 2008Co-Authors: Samuel Kimani, Albert W NyongesaAbstract:This study investigated the effects of fresh khat Extract on learning and memory in CBA mice. A total of 20 male CBA mice, weighing 20–30 g, 5–6 weeks old were administered intraperitoneally with a single daily dose of khat Extract for 5 days. The animals were divided into four groups, each comprising five animals. The first three groups were administered three doses (40, 120 and 360 mg/kg body weight) of khat Extract, respectively. The last group served as controls and was administered with 0.5 ml normal saline intraperitoneally. The animals were then subjected to Morris water maze (MWM) task performance. Moderate and high doses (120 and 360 mg/kg body weight) of khat Extract significantly impaired (P < 0.05) while low dose (40 mg/kg body weight) of khat Extract did not have a significant effect on CBA mice acquisition learning. The high dose of khat Extract significantly (P < 0.05) improved while moderate and low doses impaired accuracy for spatial memory of the platform location. This study has shown that khat Extract has selective effect on spatial learning and memory, with low dose having no effect on learning but impairing memory, whereas high dose impairs learning but improves memory.
-
effect of single and daily khat Catha Edulis Extract on locomotor behaviour in cba mice
2008Co-Authors: Samuel KimaniAbstract:It has been demonstrated that administration of cathinone is capable of increasing locomotor activity in animals. The present study was carried out with a psychostimulant Catha Edulis Extract. In this experiment, twenty CBA male mice, weighing 20 to 30 g, 5 to 6 weeks old were injected intraperitoneally with a single dose khat Extract. Thereafter, they were continued to be injected daily with single daily khat Extract for seventeen (17) days. The animals were divided into one controls group (injected 0.5 ml normal saline) and three experimental groups (injected 40, 120 and 360) mg/kg body weight khat Extract, respectively. The animals were then submitted to open field task performance. Line crossings, centre square and rearing frequency were observed at 5 min block interval for 55 min. Single high dose (360 mg/kg) body weight khat Extract significantly (P < 0.001) enhanced the line crossing in CBA mice. However, single low khat Extract (40 and 120 mg/kg body weight) dose had no effect on the line crossing. On the other hand, single khat Extract doses (40, 120 and 360 mg/kg) body weight significantly (P < 0.001) inhibited the centre square and rearing frequencies in CBA mice. Generally, single daily khat Extract (40, 120 and 360 mg/kg) body weight treated CBA mice had significantly (P < 0.001) higher line crossings than control and single dose treated animals. The centre square and rearing frequencies were significantly higher (P < 0.05) in CBA mice injected with single daily doses of khat than the single dose treated group. However, mice treated with single daily doses (40, 120 and 360) mg/kg body weight khat Extract had significantly (P < 0.05) lower rearing frequency than the control. Mice treated with 40 mg/kg b.wt single daily khat Extract had higher (P < 0.05) centre square frequency than the control and mice injected with 120 and 360 mg/kg body weight khat Extract. We demonstrate that repeated single daily khat causes behavioral sensitization, affecting both locomotor and anxiety behaviours.