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Activation of the apoptotic pathway has been associated with promoting neuronal cell death in the pathophysiology of Parkinson disease (PD). Nonetheless, the mechanisms by which it may occurs remain unclear. It has been suggested that stress-induced oxidation and potentially apoptosis may play a major role in the progression of PD. Thus, in this study, we aimed to investigate the effect of subchronic restraint stress on striatal dopaminergic activity, iron, p53, caspase-3, and plasmatic acetylcholinesterase (AChE) levels in an animal model of PD induced by administration of 6-hydroxydopamine(6-OHDA) in the medial forebrain bundle (MFB). The obtained results showed that restraint stress exacerbates motor coordination deficits and anxiety in animals treated with 6-OHDA in comparison to animals receiving saline, and it had no effect on object recognition memory. On another hand, 6-OHDA decreased dopamine(DA) levels, increased iron accumulation, and induced overexpression of the pro-apoptotic factors caspase-3, p53, and AChE. More interestingly, post-lesion restraint stress exacerbated the expression of caspase-3 and AChE without affecting p53 expression. These findings suggest that subchronic stress may accentuate apoptosis and may contribute to DA neuronal loss in the striatal regions and possibly exacerbate the progression of PD.

This article presents the development of a “small contraction” sensor fabricated using 3D printing and intended for practical works of biology; with the aim to replace the traditionally used system. This fabricated sensor is then integrated into a Computer Assisted Experiment (CAE) environment. CAE is a teaching technology that allows the students to carry out the acquisition and the processing of their data on computer (saving, adding comments, amplification…). The combination of these two technologies (CAE and 3D printing) has made it possible to equip low-cost multipurpose labs requiring minimal maintenance and where the work space is standardized. The result of a survey conducted with the students at the end of the lab sessions shows that 79.1% of them prefer the use of the new system, given the advantages it offers in terms of better understanding of the practical works objectives, time saving and the data processing functionalities it provides.

Cerebral metabolic abnormalities are common in neurodegenerative diseases. Previous studies have shown that mitochondrial damage alters ATP production and increases Reactive Oxygen Species (ROS) release which may contribute to neurodegeneration. In the present study, we investigated the neuroprotective effects of cannabidiol (CBD), a non-psychoactive component derived from marijuana (Cannabis sativa L.), on astrocytic bioenergetic balance; in a primary cell culture model of lipopolysaccharide (LPS)-induced neurotoxicity. Astrocytic metabolic profiling using an extracellular flux analyzer demonstrated that CBD decreases mitochondrial proton leak, increased spare respiratory capacity and coupling efficiency in LPS-stimulated astrocytes. Simultaneously CBD increased astrocytic glycolytic capacity and glycolysis reserve in a cannabinoid receptor type 1 (CB1) dependent manner. CBD-restored metabolic changes were correlated with a significant decrease in the pro-inflammatory cytokines tumor necrosis factor (TNF) and interleukin-6 (IL-6) concentration, and a reduction of ROS production in LPS-stimulated astrocytes. These results suggest that CBD may inhibit LPS-induced metabolic impairments and inflammation by enhancing astrocytic metabolic glycolysis versus oxidative phosphorylation through its action on CB1 receptors. The present findings suggest CBD as a potential anti-inflammatory treatment in metabolic pathologies and highlight a possible role for the cannabinoidergic system in the modulation of mitochondrial oxidative stress.

Chronic exposure to cocaine alters inflammatory signalling pathways in the brain, activates microglia and induces cognitive and motivational behavioural impairments. The endocannabinoid system may mediate cocaine’s effects. In the present study, we investigated the modulatory effects of the cannabinoid CB2 receptor agonist JWH-133 on cocaine-induced inflammation and motivational behavioural changes in vivo, and the possible effects of fractalkine (CX3CL1) on primary microglia metabolic activity and its subsequent contribution to cocaine-induced neurotoxicity. Our findings show that the CB2-specific receptor agonist, JWH-133, significantly attenuated the reinstatement of cocaine-induced CPP, increased Δ-FOSB expression in the nucleus accumbens (Nac), increased CX3CL1 levels in the ventral tegmental area (VTA) and prefrontal cortex (PFC), and decreased IL-1β in the PFC and NAc of cocaine treated animals. On the other hand, stimulation of the cortical primary microglial cells with CX3CL1 induced a biphasic effect. At a low concentration of 50 nM, CX3CL1 decreased mitochondrial oxidative metabolism vs glycolysis, and decreased the release of the proinflammatory cytokine, IL-1β, but did not affect TNFα. However, a dose of 100 nM of CX3CL1 increased mitochondrial oxidative metabolism, and both, IL-1β and TNFα release. These findings demonstrate that CB2 cannabinoid receptor modulation alters cocaine-induced reward-seeking behaviour and related neurobiological changes and highlights a potential role for CX3CL1 in the modulation of microglial metabolic and inflammatory-mediated activities.

Strawberry tree (Arbutus Unedo L.) is one of the evergreen trees that grow spontaneously in Moroccan forests. This tall shrub is traditionally used in grazing zones of some Moroccan areas, especially during the dry season, but its value in Morocco has still been underestimated. In this paper, the nutritional composition of A. unedo leaves sample collected from seven Moroccan regions has been assessed. For this, the leaves were dried, crushed, and chemically analyzed for their proximate composition, energetic value, total and reducing sugar, and mineral composition. Results of this study suggested that samples from BniAarouse (BA) region showed the highest contents of essential nutrients such as proteins, dietary fiber, ashes, and fat with average values of 7.53, 17.89, 4.14, and 8.05 g/ 100 g of dry weight, respectively, which positively influences its consumption by small ruminants. Cluster analysis based on surveyed parameters separated the strawberries individuals into four distinct groups, providing a high variability among and within studied locations. That could be related to the diversity of the edaphoclimatic conditions between regions and to the genetic effect. The results of the present study highlighted the potential use of leaves as livestock feed, with intermediate quality, and promotes their optimal cultivation and subsequent domestication in Morocco.

Background: Cancer is a multifactorial disease involving individual, behavioral and environmental factors that can contribute to its onset. More than 40% of cancers are estimated to be attributable to avoidable risk factors, particularly diet, physical activity, weight status, and alcohol consumption. Aim: To provide insight into the role of weight status, diet, and physical activity in cancer causation and prevention, and to highlight evidence-based recommendations. Material and methods: A literature review of published studies, particularly recent systematic reviews, meta-analyses, and large prospective studies was conducted using PubMed/Medline, ScienceDirect, and Google Scholar databases. Results: There is evidence that diets high in red and processed meats, fat and refined carbohydrates, and low in plant foods such as vegetables, fruits, and whole grains, high consumption of alcohol, overweight/obesity, and physical inactivity are associated with increased risk of tumor development and progression. Therefore, the current recommendations for cancer prevention are based on: (1) eating at least five portions (400g) of vegetables (3 portions) and fruits (2 portions); (2) limiting the consumption of alcohol and unhealthy foods such as red and processed meats, energy-dense foods, and trans-fatty acids; (3) maintaining a healthy weight status; and (4) being at least moderately physically active. Conclusion: While a balanced diet, as defined by the recommendations, can help reduce the risk of certain cancers, no single food can prevent the development of this pathology. The term "anticancer" associated with diet is therefore misleading. Several nutritional factors are associated with an increase or a decrease in the risk of certain cancers. Adopting a healthy and plant-based diets, avoiding overweight/obesity, and being physically active are considered as cornerstones of preventive strategies against cancer. Further studies are needed to elucidate the associations between dietary and lifestyle patterns and cancer. Keywords: Cancer, Diet, Weight status, Overweight, Obesity, Physical activity.

Almond oil, a rich source of macronutrients and micronutrients, is extracted for food flavorings and the cosmetics industry. In recent years, the need for high-quality and high-quantity production of almond oil for human consumption has been increased. The present review examines the chemical composition of almond oil, storage conditions, and clinical evidence supporting the health benefits of almond oil. From the reviewed studies, it appears that almond oil contains a significant proportion of poly and monounsaturated fatty acids, with oleic acid as the main compound, and an important amount of tocopherol and phytosterol content. Some variations in almond oil composition can be found depending on the kernel's origin and the extraction system used. Some new technologies such as ultrasonic-assisted extraction, supercritical fluid extraction, subcritical fluid extraction, and salt-assisted aqueous extraction have emerged as the most promising extraction techniques that allow eco-friendly and effective recovery of almond oil. This safe oil was reported by several clinical studies to have potential roles in cardiovascular risk management, glucose homeostasis, oxidative stress reduction, neuroprotection, and many dermatologic and cosmetic applications. However, the anticarcinogenic and fertility benefits of almond oil have yet to be experimentally verified.

The Culex pipiens mosquito (Diptera: Culicidae) is highly suspected to be the vector responsible for the spread of several parasitic and viral diseases. The use of synthetic insecticides is generally the preferred method of controlling these mosquitoes’ proliferation. However, it has led to resistance problems in target mosquitoes and environmental damage. Hence, diverse plant extracts could be considered as an alternative and potential source as mosquito control agents. In this study, essential oils of Lavandula angustifolia subsp. angustifolia and Lavandula dentata spp. dentata that are growing in Morocco were examined for their insecticidal effects on Culex pipiens larvae. The bioassay was performed according to a methodology inspired by the standard protocol of the World Health Organization. The mortality rate was determined after 24 hours of exposure, and probit regression analysis was used to calculate LC50 and LC90. The chemical analysis revealed that the principal compounds of L. angustifolia subsp. essential oils include linalool, linalyl acetate, geraniol, lavandulyl acetate, camphor, β-caryophyllene, terpinen-4-ol, β-myrcene, and 1,8-cineole, while the essential oil of L. dentata spp. was mainly composed of 1,8-cineole, camphor, α-pinene, trans-pinocarveol, linalool, and borneol. These volatile compounds have shown a toxic effect against Culex pipiens larvae, with lethal concentrations LC50 and LC90 being, respectively, 140 µg/ml and 450 µg/ml, for the L. angustifolia subsp. essential oil. Meanwhile, they were estimated at 2670 µg/ml and 7400 µg/ml, respectively, for the L. dentata spp. essential oil. These results suggest using essential oils of two species of Lavandula to control the Culex pipiens mosquito. It could be useful for the study of new natural larvicidal compounds.

Background: Cancer is a multifactorial disease involving individual, behavioral and environmental factors that can contribute to its onset. More than 40% of cancers are estimated to be attributable to avoidable risk factors, particularly diet, physical activity, weight status, and alcohol consumption. Aim: To provide insight into the role of weight status, diet, and physical activity in cancer causation and prevention, and to highlight evidence-based recommendations. Material and methods: A literature review of published studies, particularly recent systematic reviews, meta-analyses, and large prospective studies was conducted using PubMed/Medline, ScienceDirect, and Google Scholar databases. Results: There is evidence that diets high in red and processed meats, fat and refined carbohydrates, and low in plant foods such as vegetables, fruits, and whole grains, high consumption of alcohol, overweight/obesity, and physical inactivity are associated with increased risk of tumor development and progression. Therefore, the current recommendations for cancer prevention are based on: (1) eating at least five portions (400g) of vegetables (3 portions) and fruits (2 portions); (2) limiting the consumption of alcohol and unhealthy foods such as red and processed meats, energy-dense foods, and trans-fatty acids; (3) maintaining a healthy weight status; and (4) being at least moderately physically active. Conclusion: While a balanced diet, as defined by the recommendations, can help reduce the risk of certain cancers, no single food can prevent the development of this pathology. The term "anticancer" associated with diet is therefore misleading. Several nutritional factors are associated with an increase or a decrease in the risk of certain cancers. Adopting a healthy and plant-based diets, avoiding overweight/obesity, and being physically active are considered as cornerstones of preventive strategies against cancer. Further studies are needed to elucidate the associations between dietary and lifestyle patterns and cancer.

Aristolochia longa L. (Aristolochiaceae) is an herbaceous plant recognized in alternative medicine for its many therapeutic virtues. The aim of this study was to determine the pharmacotoxicological effects of this plant in order to ensure safe clinical use. The oral toxicity of the aqueous extract of A. longa roots was performed in vivo on Wistar rats at doses of 0.8, 1.25, 2, 2.5, and 5 g/kg/day for 21 days. Clinical signs were observed throughout the experimental period, followed by measurement of body weight change, while selected biochemical parameters, as well as relative organ weights and the histology of liver, kidney, and intestinal tissues, were evaluated after 6, 11, and 16 days and then at the end of 21 days of daily administration. At repeated doses for 21 days, the extract contributed to significant weight gain, in both control and treated rats. The global analysis of hepatic and renal biomarkers showed a significant increase between control and different doses of the extract, from the first to the third week of treatment, indicating the likely toxic effect of the extract on liver and kidney function. Organ toxicity was confirmed by histopathological examination, which revealed greater renal and hepatic parenchymal changes in animals treated with a high dose beyond the 16th day. At the end of the treatment, relatively small size of intestinal villi was also observed. It was concluded that ALAE has a low toxicity potential in nonprolonged oral administrations. However, at high chronic oral doses, A. longa appears to have significant toxicity on the organs tested.

Current therapeutic for the treatment of anxiety is associated with a wild variety of prominent side effects. The traditional use of plant extract to health care can indicate an important source of new pharmaceuticals. In Morocco traditional medicine, the use of Mercurialis annua is commonly recommended for relief of anxiety. Nevertheless, despite its popular use there are no studies related to its possible neuropharmacological effect. Here, we investigated the possible anxiolytic effect of the extract of M.annua after acute treatment in mice. The methanolic extract from the aerial parts of M.annua (100, 200 or 400 mg/kg) was orally administered, and its anxiolytic effect was evaluated in hole board test, the light–dark box test, and motor coordination with the rota rod test. Diazepam was employed as standard drug 1mg/kg. The methanolic extract of Ma 100 mg/kg increased the time spent in the brightly-lit chamber of the light/dark box, as well as in the number of times the animal crossed from one compartment to the other. Performance on the rota rod was unaffected. In the hole board test, the extract significantly increased head-dip counts. These results provides support for anxiolytic activity of Mercurialis annua, in line with its medicinal traditional use, and may also suggest a better side-effect profile of Mercurialis annua relative to diazepam.

The objective of this work was to investigate the cytotoxicological effect of the extracts (hexane, ethyl acetate, and n-butanol) of Cotula cinerea and Salvia verbenaca in addition to the essential oil of Cotula cinerea. These plants are widely used in the Moroccan traditional folk medicine. The cytotoxic effect was explored against two cancer cell lines, Vero and RD, using the colorimetric MTT assay. The obtained results showed that the cytotoxicity differed according to the used extract with an efficient effect of Cotula cinerea extracts compared to Salvia verbenaca. A potent cytotoxicity was thus observed for the Cotula cinerea hexane extract which inhibited the growth of RD cell line at the lowest IC50 value (57.21±3.43 µg/mL). This was followed by the ethyl acetate extract and the essential oil with moderate effects against RD cell line and showed IC50 values of 187.52±6.27 µg/mL and 173.05±4.46 µg/mL, respectively. On the other hand, different results were obtained and Cotula cinerea essential oil was the most cytotoxic with the lowest IC50 value (72.72±2.18 µg/mL) against Vero cell line. In the same conditions, higher concentrations were needed in the case of Salvia verbenaca extracts. The results of this study showed thus that Cotula cinerea essential oil and hexane extract showed significant cytotoxic effects against RD and Vero cell lines, respectively, and could be considered as novel source of antitumor agents. This study is expected to be beneficial for clinical and traditional applications for Cotula cinerea as a remedy against cancer and opens new perspectives for further investigations on other types of cancer cell lines.

Chronic cannabinoid exposure during adolescence in male rats induces chronic cognitive and emotional impairments. However, the impact of this form of exposure on offspring vulnerability to stress is unknown. The aim of this study was to evaluate the behavioural and epigenetic effects of stress in the offspring of male rats whose fathers were exposed to cannabinoids during adolescence. Male adolescent offspring of Win55,212-2 (1.2 mg/kg) treated rats were exposed during one week to variable stressors and subjected to behavioural tests of anxiety and episodic-like memory, followed by an assessment of global DNA methylation and expression of DNA methyltransferases enzymes DNMT1 and DNMT3a mRNA in the prefrontal cortex. Stress exposure induced a significant anxiogenic-like effect but did not affect the episodic-like memory in the offspring of Win55,212-2 exposed fathers in comparison to the offspring of non-exposed fathers. These behavioural changes were subsequent to a significant increase in global DNA methylation and DNMT1 and DNMTa3 transcription in the prefrontal cortex. These data suggest that the deleterious effect of chronic exposure to cannabinoids during adolescence are not limited to the exposed individuals but may increase the vulnerability to stress-induced anxiety in the offspring and alter their epigenetic programming.

The objective of our work is to make a pharmacological study of molecules derived from 4-phenyl-1,5-benzodiazepin-2-one carrying long chains so that they have a structure similar to surfactants, with the benzodiazepine as a hydrophilic head and a carbon chain as a hydrophobic tail. First, we studied the acute toxicity of the above mentioned 4-phenyl-1,5-benzodiazepin-2-one derivatives. This study was conducted according to OECD 423 guidelines in female mice and revealed that these compounds are nontoxic. We then assessed the psychotropic effects of our products on the central nervous system (CNS). The results obtained show that 4-phenyl-1,5-benzodiazepin-2-one has no sedative effect at therapeutic doses of 100 and 200 mg/kg. On the other hand, its long-chain derivatives possess them. Moreover, all these products have no cataleptic and hypnotic effects at the doses studied. But at 100 mg/kg, these compounds all have the ability to significantly prolong the hypnotic effect of thiopental sodium.

Background: Anxiety is an unpleasant state of inner turmoil often accompanied by cognitive, somatic, emotional, and behavioral components. There is some evidence in traditional medicine for the effectiveness of Urtica urens in the treatment of anxiety in humans. The present study was designed to study anxiolytic property of aqueous extracts of Urtica urens; an important and commonly used for its medicinal properties belongs to urticaceae family. Methods: The anxiolytic activity was evaluated with the adult mice by hole board test, and the light-dark box test, and motor coordination with the rota rod test. The efficacy of the plant extract (100–400 mg/kg) was compared with the standard anxiolytic drug diazepam (1 mg/kg i.p.). Results: The extract increased the time spent in the brightly-lit chamber of the light/dark box, as well as in the number of times the animal crossed from one compartment to the other. Performance on the rota rod was unaffected. In the hole board test, the extract significantly increased both head-dip counts and head-dip duration. Urtica urens, in contrast to diazepam, had no effect on locomotion. Conclusions: These results provides support for anxiolytic activity of Urtica urens, in line with its medicinal traditional use, and may also suggest a better side-effect profile of Urtica urens relative to diazepam.

Introduction: Damage to the Septum or to the Prefrontal cortex impairs learning and the flexibility of the early attention-related stages of information porocessing. These brain regions are the goals, respectively, of the dopaminergic (DA) mesolimbic and mesocortical pathways emanating from the ventral tegmental A 10 nuclei (VTA). These areas are represented in the "convergent nodes" and "circuit systems" we have described as a basis for the functional influence of DA on integrative function, see Figure 1 and 2, and Oades and Halliday, 1987 Here we elaborate the use of the measurement of a search strategy (for 4 food-holes in a 16 hole board) in rodents as a measure of the influences affecting attention to cues and the establishment of a working memory: in particular we examined the effects of local VTA injections of a DA agonist and antagonist on the stability of the normally consistent sequence of hole visits, and concentrate on the mesolimbic system. We also present preliminary results of the effect of septal 6-OHDA lesions on the conditioned blocking measure of selective attention in a shuttle avoidance task. Methods: Animals were given 10 trials/session, 2 sessions/day for 5 days on a 16-hole board in a closed arena. A food pellet was placed in the same 4 holes on each occasion. Prior to session 4 and 7 the rats received either the DA D2 antagonist spiroperidol (2µg/0.5µl) or the DA agonist apomorphine (2 µg/0.5µl) or the vehicle (saline or pH adjusted tartarate) into the VTA. (Diffusion was restricted to within 1.5 mm.) It would be predicted that local neuroleptic treatment would block local, inhibitory autoreceptors and thus lead to increased DA activity in the terminal regions. Monoamines and their metabolites in the N. accumbens were measured with HPLC. Results: 1/ Neuroleptic, but not other VTA-treatments, increased rearing (3-4 fold), non-food-hole visits / errors (50-100%) and the number of switches away from the preferred hole-visit sequence established on the first 3 sessions. 2/ An increase of DA utilization in the nucleus accumbens was demonstrated in selected animals sacrificed after session 7. 3/ There was a significant correlation for increased DA utilization with the number of errors (of working- and reference-memory type), the amount of rearing, but not with switches away from the preferred search sequence. 4/ Septal-6-OHDA damage did not alter conditioned blocking considered across all test trials - but this masked an initial mild attenuation followed by exaggerated blocking at the end of testing (see Oades et al., 1987 for a full report). Conclusions: On the basis of the disruption of holeboard search by increased DA activity it is postulated that mesolimbic DA is important for the evaluation and temporal coordination of response feedback for the pursuance of task-solving strategies. The changeover from reduced to enhanced conditioned blocking after septal-6-OHDA treatment is discussed in the context of where septal damage induces 'changeovers' in other situations, and seen to be consistent with the interpretation that mesolimbic DA modulates the evaluation of attended stimuli and the formation of working memory templates. (The holeboard work started with investigation of hippocampal lesions and haloperidol treatment as an animal model for schizophrenia, Oades and Isaacson, 1978; Oades, 1981 and continued with studies of the role of the VTA A 10 DA system in Oades, 1981a, 1981b and 1982 ).

Introduction: The frequency of spontaneous alternation in a Y-maze (visiting each arm in turn at p>50%) depends on the influence of the attention given to intra- and extra-maze cues. We examined the observing responses shown by rats (collateral rearing and head-turning behaviour), the habituation to the novelty and alternation responses over 15 minutes/day, four days in a row - in a Y-maze under enhanced and reduced dopamine (DA) activity (amphetamine- and haloperidol treatment). Methods: Prior to placement in a Y-maze for 15 minutes observation on 4 successive days animals were treated with either amphetamine (0.5 or 2.5 mg/kg) or pre-treated with a low dose of haloperidol (0.08 mg/kg, ip). Results: 1/ Amphetamine treated animals chose the arms at random on day 1, but after the higher dose on day 2-4 they perseverated their choice. The controls maintained their alternation over this period. 2/ The amphetamine-induced effects on alternation were prevented by prior treatment with the neuroleptic haloperidol. 3/ Amphetamine treatment increased the frequency of rearing in the middle at the choice point of the Y-maze. Haloperidol pre-treatment blocked this increase at the midpoint on day 1, and blocked the rearing behavior at the end of an arm on day 2. 4/ Amphetamine also increased the frequency of head turning and "looking", - an effect that was also prevented by haloperidol. (day 2 onwards). 5/ Haloperidol increased the duration of" looking" and of rearing at the end of an arm later in testing. Conclusions: Two effects are postulated to have occurred. a) a conflict on day 1 between the novelty-controlled sensory or attentional effects, that leads to an alternation of arm-choice, and amphetamine-induced DA activity that facilitates an alternation of behavioural responses: -- the result was random choice and increased rearing at the choice point. b) On days 2-4 the drug-induced effects on switching motor responses came to control behaviour (cf. Oades, 1985 review on the role of DA activity in switching between alternative sources of information).

The study and the method: The locomotor activity of adult male Sprague-Dawley was automatically recorded in a circular corridor - circadian changes are described as well as the response to the novel situation and its habituation over three hours. Four groups of animals were compared, - those with sham/vehicle operations and those with 6-OHDA dopamine (DA) depleting lesions in - the frontal cortex, the limbic septum, and the ventral tegmental area (VTA - A10). Results: 1/ Lesions of the VTA resulted in increased dark-phase activity, - and a large response to an apomorphine challenge in comparison to other lesion and control groups: 2/ Septal 6-OHDA lesions did not alter locomotion: 3/ After frontal DA depletion there was a small increase of locomotion after the apomorphine challenge, that might reflect increased receptor sensitivity in cortical or sub-cortical areas: (Table 1: HPLC measures of NA, DA and DOPAC for each group in the prefrontal cortex, septum and N. accumbens) Figure 1 illustrates the cumulative photocell counts per hour over 24 hours for the 4 groups:. Figure 2 illustrates the cumulative photocell counts every 10 minutes over 90 minutes post-apomorphine treatment - maximal at 20-30 minutes and habituating over 60 minutes (90 minutes for the VTA group): overall activity VTA >> Frontal > Septal > Controls. Conclusions: Along with correlations found for motor activity with cortical levels of DA and NA, these results are interpreted to support a role for DA, NA and the region of the frontal cortex in modulating locomotion that is primarily mediated by mesolimbic VTA - accumbens - DA activity.

Introduction: The performance of rats on the conditioned blocking test (CB) of learned inattention was measured in a two-way shuttle avoidance task after sham and dopamine (DA) - depleting lesions of the frontal cortex, the limbic septum, and the ventral tegmental area (VTA - A10). Methods: Animals were trained on two sessions with tone and / or light as conditioned stimuli. One group was trained with both stimuli on both sessions. A second group was trained on the first session with one stimulus and on the second with both stimuli. The blocking of conditioning to the added stimulus (b) was tested by presenting the stimuli (a and b) separately and measuring the blocking ration (avoidance to b/a + b) and response latencies. Results: 1/ No deficits were recorded on tests of sensory and motor ability; 2/ The VTA group alone showed a hyperlocomotor response to apomorphine treatment, - and did not acquire the avoidance response (i.e. did not learn the active avoidance task); 3/ The appearance of blocking in the septally lesioned group was delayed until the end of the 20-trial test session - then it was exaggerated; 4/ Blocking was mildly attenuated in the frontally lesioned group. 5/ Dopamine (DA) levels were depleted by about 80% and noradrenaline (NA) levels by, respectively, 20% and 50% in the frontal and septal regions. Figure 2 illustrates a) the CB impairment in the frontal group relative to sham controls, and b) the late development of "supr-blocking" in septally-damage animals. Figure 3 illustrates the results of the HPLC analysis for NA, DA and DOPAC in frontal cortex, septum, N. accumbens and striatum after 6-OHDA lesions (& vehicle treatment) in the frontal, septal, and VTA areas. Conclusions: The results show that the levels of DA activity, or rather the balance between the activity of DA and NA in frontal and limbic regions can contribute to efficient associative conditioning and / or the normal ability of rats not to attend to a redundant stimulus.

Background The present study was designed to study anxiolytic property of methanolic extracts of Urtica urens; an important and commonly used for its medicinal properties belongs to urticaceae family. Methods The anxiolytic activity was evaluated with the adult mice by hole board test, and the light–dark box test, and motor coordination with the rota rod test. The efficacy of the plant extract (100–400 mg/kg) was compared with the standard anxiolytic drug diazepam (1 mg/kg i.p.) Results The extract increased the time spent in the brightly-lit chamber of the light/dark box, as well as in the number of times the animal crossed from one compartment to the other. Performance on the rota rod was unaffected. In the hole board test, the extract significantly increased both head-dip counts and head-dip duration. Urtica urens, in contrast to diazepam, had no effect on locomotion. Conclusions These results provides support for anxiolytic activity of Urtica urens, in line with its medicinal traditional use, and may also suggest a better side-effect profile of Urtica urens relative to diazepam.