Pycnogenol ameliorates motor function and gene expressions of NF-ƙB and Nrf2 in a 6-hydroxydopamine-induced experimental model of Parkinson's disease in male NMRI mice.

We investigated the effect of Pycnogenol as an antioxidant on improving motor function, depression, and the expression of NF-ƙB and Nrf2 genes in the experimental model of Parkinson's disease. Forty adult male NMRI mice weighing about 30 g were randomly divided into five groups of eight. Saline group: received 3 µl of saline, as 6-hydroxydopamine (6-OHDA) solvent, unilaterally in the left striatum, treatment groups: first received 3 µl 6-OHDA unilaterally inside the ipsilateral striatum and then divided into subgroup A: received distilled water, Pycnogenol solvent, by gavage for 7 days (lesion group), and subgroup B: received Pycnogenol at doses of 10, 20, and 30 mg/kg by gavage for 7 days. Seven days after Parkinson's model induction, the apomorphine test, the degree of catalepsy by bar test, the duration of immobility (depression) by forced swimming test (FST) were measured. In addition, the expression of NF-ƙB and Nrf2 genes was measured using the real-time PCR technique. The total number of rotations in the apomorphine test decreased significantly in the groups receiving Pycnogenol. Administration of Pycnogenol significantly reduced catalepsy. The study of depression in the group receiving Pycnogenol showed a significant reduction. Also, Pycnogenol increased the expression of the Nrf2 anti-inflammatory gene, but it had no significant difference in the expression of NF-ƙB gene. Pycnogenol, presumably with its antioxidative and genomic effects, improves the expression of the anti-inflammatory gene and found that neuroprotection effect in the brain.

Complementary effects of coenzyme Q10 and Lepidium sativum supplementation on the reproductive function of mice: An experimental study.

BACKGROUND: Coenzyme Q10 (CoQ10) and Lepidium sativum (LS) have therapeutic effects on infertility. OBJECTIVE: To evaluate the combined effects of LS and CoQ10 on reproductive function in adult male NMRI mice. MATERIALS AND METHODS: Eighty three-months-old male mice (35-40 gr) were divided into four groups (n = 10/each): control (treated with water), CoQ10-treated (200, 300, and 400 mg/kg/body weight), LS-treated (200, 400, 600 mg/kg/body weight), and co-treated (LS [600 mg/kg/body weight] + CoQ10 [200 mg/kg/body weight]) groups. Serum testosterone, luteinizing hormone, follicle-stimulating hormone, and gonadotropin realizing hormone (GnRH) levels were measured using ELISA method. The sperm quality was assessed using Sperm Class AnalyzerⓇ (SCA) CASA system and GnRH mRNA expression levels were evaluated by real-time polymerase chain reaction. RESULTS: The number of sniffing and following behavior was significantly higher in LS-treated (400 and 600 mg/ml/body weight) groups than the control group (p = 0.0007 and p = 0.0010, respectively). The number of mounting and coupling behaviors was significantly higher in the CoQ10 (300 and 400 mg/ml/body weight)-treated animals than the control group (p = 0.0170 and p = 0.0006, respectively). Co-treatment of CoQ10 (200 mg/ml/body weight) and LS (600 mg/ml/body weight) significantly increased all aspects of sexual behaviors as well as the levels of serum testosterone (p = 0.0011), luteinizing hormone (p = 0.0062), and follicle-stimulating hormone (p = 0.0001); sperm viability (p = 0.0300) and motility (p = 0.0010); and GnRH mRNA levels (p = 0.0016) compared to the control group. CONCLUSION: The coadministration of CoQ10 and LS significantly improves the activity of the hypothalamic-pituitary-gonadal axis and enhances the reproductive parameters in adult male mice.

Prenatally traumatized mice reveal hippocampal methylation and expression changes of the stress-related genes Crhr1 and Fkbp5.

In our previous study, we found that prenatal trauma exposure leads to an anxiety phenotype in mouse pups, characterized by increased corticosterone levels and increased anxiety-like behavior. In order to understand the mechanisms by which aversive in utero experience leads to these long-lasting behavioral and neuroendocrine changes, we investigated stress reactivity of prenatally traumatized (PT) mice, as well as the expression and methylation levels of several key regulatory genes of the stress axis in the dorsal hippocampus (dHPC) of the PT embryo and adult mice. We detected increased corticotropin-releasing hormone receptor 1 (Crhr1) and decreased FK506 binding protein 5 (Fkbp5) mRNA levels in the left dHPC of adult PT mice. These alterations were accompanied by a decreased methylation status of the Crhr1 promoter and an increased methylation status of the Fkbp5 promoter, respectively. Interestingly, the changes in Fkbp5 and Crhr1 mRNA levels were not detected in the embryonic dHPC of PT mice. Together, our findings provide evidence that prenatal trauma has a long-term impact on stress axis function and anxiety phenotype associated with altered Crhr1 and Fkbp5 transcripts and promoter methylation.

αCaMKII autophosphorylation mediates neuronal activation in the hippocampal dentate gyrus after alcohol and cocaine in mice.

Psychoactive drug-induced cellular activation is a key mechanism to promote neuronal plasticity and addiction. Alpha Ca(2+)/calmodulin-dependent protein kinase II (αCaMKII) and its autophosphorylation play a key role in the development of drug use associated behaviours. It has been suggested that αCaMKII autophosphorylation is necessary for drug-induced neuronal activation in the mesolimbic system. Here, we show an alcohol- and cocaine-induced increase in c-fos expression in the hippocampal dentate gyrus, which is absent in αCaMKII(T286A) autophosphorylation deficient mice. These findings may suggest a role in hippocampal αCaMKII autophosphorylation in the acute neuroplastic effects of alcohol and cocaine.

Inverse effects of lipopolysaccharides on anxiety in pregnant mice and their offspring.

This study aimed to evaluate the effects of the bacterial lipopolysaccharide (LPS) exposure during early pregnancy on anxiety-related behaviour of both pregnant female mice and their male offspring. Pregnant NMRI mice were treated with subcutaneous injections of LPS (30, 60, 120, 240 and 480 µg/kg) on the tenth gestational day of pregnancy. Pro-inflammatory cytokines, such as TNF-α, IL-1ß, IL-6 and corticosterone levels, were measured in maternal serum 1.5h following the LPS injections. Baseline anxiety levels of pregnant mice (1.5h after LPS administration) and their male offspring (at postnatal days 60-70) were investigated with the elevated plus maze (EPM) test. In addition, anxiety levels in the offspring were measured after 2h restraint stress or TNF-α (10 µg/kg) administration. Our results demonstrate that LPS administration induces anxiety-like behaviour and a significant increase in cytokines and corticosterone levels in maternal serum. However, in male offspring, prenatal LPS administration has no significant effects on serum cytokines and corticosterone secretion with an exception of the lowest LPS dose that slightly reduced corticosterone levels. Interestingly, prenatal LPS treatment seemed to decrease the baseline anxiety levels, while pretreatment with restraint stress or TNF-α abolished this anxiolytic effects. In summary, our results suggest that prenatal exposure to LPS during early pregnancy may result in reduced baseline anxiety in adult male offspring.

αCaMKII autophosphorylation controls the establishment of alcohol drinking behavior.

The α-Ca(2+)/calmodulin-dependent protein kinase II (αCaMKII) is a crucial enzyme controlling plasticity in the brain. The autophosphorylation of αCaMKII works as a 'molecular memory' for a transient calcium activation, thereby accelerating learning. We investigated the role of αCaMKII autophosphorylation in the establishment of alcohol drinking as an addiction-related behavior in mice. We found that alcohol drinking was initially diminished in αCaMKII autophosphorylation-deficient αCaMKII(T286A) mice, but could be established at wild-type level after repeated withdrawals. The locomotor activating effects of a low-dose alcohol (2 g/kg) were absent in αCaMKII(T286A) mice, whereas the sedating effects of high-dose (3.5 g/kg) were preserved after acute and subchronic administration. The in vivo microdialysis revealed that αCaMKII(T286A) mice showed no dopamine (DA) response in the nucleus accumbens to acute or subchronic alcohol administration, but enhanced serotonin (5-HT) responses in the prefrontal cortex. The attenuated DA response in αCaMKII(T286A) mice was in line with altered c-Fos activation in the ventral tegmental area after acute and subchronic alcohol administration. In order to compare findings in mice with the human condition, we tested 23 single-nucleotide polymorphisms (SNPs) in the CAMK2A gene for their association with alcohol dependence in a population of 1333 male patients with severe alcohol dependence and 939 controls. We found seven significant associations between CAMK2A SNPs and alcohol dependence, one of which in an autophosphorylation-related area of the gene. Together, our data suggest αCaMKII autophosphorylation as a facilitating mechanism in the establishment of alcohol drinking behavior with changing the DA-5-HT balance as a putative mechanism.

Activation of GABAA receptors in the medial prefrontal cortex produces an anxiolytic-like response.

OBJECTIVES: There has been increasing evidence that the γ-aminobutyric acid (GABA)ergic system is involved in the neurobiology of anxiety. The present study aimed to investigate the role of GABAergic systems in the modulation of anxiety in the medial prefrontal cortex (mPFC) of rats using the elevated plus maze test. METHODS: Rats were anaesthetised with a mixture of ketamine and xylazine, and then special cannulae were inserted stereotaxically into the mPFC. After 5-7 days of recovery, the effects of intra-mPFC administration of GABAergic agents were studied. RESULTS: Bilateral injection of the GABAA receptor agonist muscimol (0.25, 0.5 and 1 µg/rat) produces an anxiolytic-like effect, shown by significant increases in the percentage of open-arm time (%OAT) and percentage of open-arm entries (%OAE). Intra-mPFC administration of the GABAA receptor antagonist bicuculline (0.25, 0.5 and 1 µg/rat) produces significant anxiogenic-like behaviour. However, intra-mPFC injection of the GABAB receptor agonist baclofen (0.05, 0.1 and 0.2 µg/rat) and the GABAB receptor antagonist CGP35348 (5, 10 and 15 µg/rat) did not alter %OAT and %OAE significantly. CONCLUSION: The results of the present study demonstrate that the GABAergic system of the mPFC modulates anxiety-related behaviours of rats through GABAA receptors.

Using experimental autoimmune encephalomyelitis as a model to study the effect of prenatal stress on fetal programming.

OBJECTIVES: There is a growing evidence to suggest that the antecedents of some adult diseases can be traced back to their fetal origins. Despite extensive research on such diseases, to our knowledge, there has been no research investigating the relationship between the origins of multiple sclerosis (MS) disease and maternal infections. The aim of this study was to examine the role of prenatal exposure to endotoxin in fetal programming with respect to induction of susceptibility/vulnerability to MS. METHODS: The pregnant dams were administered a single intraperitoneal injection of lipopolysaccharide in gestational day 10. The male offspring were weighed and examined for clinical signs of experimental autoimmune encephalomyelitis in a blinded fashion within 36 days after immunization (postnatal day 63-98). RESULTS: Our data provide the evidence showing prenatal exposures to higher doses of Lipopolysaccharide resulted in an earlier onset of the disease, an augmentation of its clinical signs, and lower body weight in the prenatally Lipopolysaccharide -treated C57BL/6 mice after the immunization. DISCUSSION: Therefore, the present research can provide evidence that prenatal stress may play a role in enhancing the clinical symptoms of experimental autoimmune encephalomyelitis/MS.

Possible Modulation of the Anexiogenic Effects of Vitex Agnus-castus by the Serotonergic System.

OBJECTIVES: There is well documented evidence for the increase in widespread use of complementary and alternative medicine in the treatment of physical and psychiatric symptoms and disorders within the populations. In the present study, we investigated the influence of V itex agnus-castus (vitex) on anxiety-like behaviors of rats. MATERIALS AND METHODS: Elevated plus maze which is one of the methods used for testing anxiety is used in our present study. Rats were orally administrated with vitex for two week. The anxiety test was carried out after two weeks of oral administration of vitex. For evaluating interaction of vitex and serotonergic systems, rats were anaesthetized with ketamine and special cannulas were inserted stereotaxically into the third ventricle (TV) of brain. After 1 week recovery, the effects of serotonegic agents on anxiety were studied. RESULTS: Oral administration of vitex (100, 200, 300 mg/kg) for two weeks induced an anxiogenic-like effect which was shown through specific decreases in the percentages of open arm time (OAT %) and open arm entries (OAE %). Intra - TV infusion of 5HT1A receptor agonist, 8-OH-DPAT (5, 10 and 25 ng/rat) increased OAT% and OAE%, indicating anxiolytic-like behavior. However, injection of 5HT1A receptor antagonist NAN190 (0.25, 0.5 and 1 µg/rat) produced anxiogenic-like behavior. The most effective dose of 8-OH-DPAT (10 ng/rat), when co-administered with vitex (100, 200, 300 mg/kg), attenuated the anxiogenic-like effects of vitex significantly. Injection of the less effective dose of NAN190 (0.5 µg/rat), in combination with vitex (100, 200, 300 mg/kg), potentiate anxiogenic effects of vitex. CONCLUSIONS: These results illustrate that 5HT1A receptor is involved in the anxiogenic effects of vitex.

Maternal infection during late pregnancy increases anxiety- and depression-like behaviors with increasing age in male offspring.

Scientific reports suggest that the exposure to long-term stressors throughout or during late gestation increase anxiety- and depression-like behaviors of offspring in their later life. Moreover, several studies concluded that increasing age correlates with increased anxiety behaviors in humans and rodents. In the present study, we assessed the effects of prenatally administration of equal lipopolysaccharide (LPS) doses in various points of late gestation (days 15, 16, and 17) period, on neuroendocrine and immunological responses of pregnant mice, and subsequent long-lasting consequences of anxiety and depression with increasing age in male offspring at postnatal days (PD) 40 and 80. Four hours after the LPS injection, levels of corticosterone (COR) and pro-inflammatory cytokines (PIC) in pregnant mice, as compared to the control dams, were increased significantly. Furthermore, maternal inflammation raised the levels of COR, anxiety- and depression-like behaviors with increasing age in male offspring in comparison with saline male offspring. These data support other studies demonstrating that maternal stress increases the levels of anxiety and depression in offspring. Additionally, our data confirm other findings indicating that increasing age correlates with increased anxiety or depression behaviors in humans and rodents. Findings of this study suggest that time course of an inflammation response or stressor application during various stages of gestation and ages of offspring are important factors for assessing neuropsychiatric disorders.

Effects of prenatal lipopolysaccharide exposure on reproductive activities and serum concentrations of pituitary-gonadal hormones in mice offspring.

BACKGROUND: Maternal infection during pregnancy is a risk factor for some behavioral problems with neurodevelopmental origin. This study aimed to evaluate the effects of exposure of pregnant mice to the bacterial lipopolysaccharide (LPS) on sexual behaviour and serum level of pituitary-gonadal hormones of offspring in adulthood. MATERIALS AND METHODS: In this Expremental study, pregnant NMRI mice (n=7/group) were treated with intra-peritoneal administration of LPS (1, 5 and 10 µg/kg) at day 10 of gestation. Induction of the pro-inflammatory cytokines, Tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1ß) and interleukin-6 (IL-6) were measured in maternal serum 2 hours following the maternal LPS challenge. Behavior in the adult male offspring reproductive activity was investigated using receptive female mice. Concentrations of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in adult offspring serum were measured using the enzyme-linked immunosorbent assay (ELISA) method (at postnatal day 60, n=10/group). RESULTS: One-way ANOVA showed that LPS administration induces a significant increase in TNF-α, IL-1ß and IL-6 levels of maternal serum. Prenatal LPS exposure reduces sexual behavior and serum concentration of LH and testosterone in adult male offspring. CONCLUSION: The overall results suggest that prenatal exposure to LPS increases pro- inflammatory cytokine levels, affects development of neuroendocrine systems and results in the inhibition of reproductive behaviors and reactivity of hypothalamic-pituitary-gonadal (HPG) axis in adult male offspring.

Role of serotonergic system on modulation of depressogenic-like effects of silymarine.

In the present study, we have investigated the effects of silymarine on depression and the possible role of serotonergic system in these effects. The rats were anesthetized intraperitoneally with ketamine hydrochloride and placed in a Stoelting stereotaxic instrument. A stainless steel guide cannula (22-gauge) was implanted in the third ventricular region. The third ventricular region was infused by means of an internal cannula (27-gauge), terminated 1 mm below the tip of the guide cannula. Forced swimming test was used for evaluating the depression. The results obtained from this study showed that oral administration of silymarin (35, 70, 140 and 280 mg/rat) for two weeks increased the immobility time in forced swimming test, indicating an increase in depression level of the treated rats. Intra-third-ventricle (Intra-TV) infusion of 5HT1A receptor agonist 8-OH-DPAT (25 and 10 ng/rat) decreased the immobility time indicating an anti-depression effect, while injection of 5HT1A receptor antagonist NAN190 (0.25, 0.5 and 1 µg/rat) had no significant effect on immobility time. An effective dose of 8-OH-DPAT (10 ng/rat) co-administered with silymarin (140 and 280 mg/rat) decreased the depressogenic effects of silymarin. These results showed that the depressogenic effects of silymarin may be modulated via 5HT1A receptor of serotonin.

5HT(1A) and 5HT(1B) receptors of medial prefrontal cortex modulate anxiogenic-like behaviors in rats.

Medial prefrontal cortex (MPFC) is one of the brain regions which play an important role in emotional behaviors. The purpose of the present study was to evaluate the role of 5HT(1A) and 5HT(1B) receptors of the MPFC in modulation of anxiety behaviors in rats. The elevated plus maze (EPM) which is a useful test to investigate the effects of anxiogenic or anxiolytic drugs in rodents, was used. Bilateral intra-MPFC administration of 5HT(1A) receptor agonist, 8-OH-DPAT (5, 10, and 50 ng/rat) decreased the percentages of open arm time (OAT%) and open arm entries (OAE%), indicating an anxiogenic response. Moreover, administration of 5HT(1A) receptor antagonist, NAN-190 (0.25, 0.5, and 1 µg/rat) significantly increased OAT% and OAE%. Pre-treatment administration of NAN-190 (0.5 µg/rat), which was injected into the MPFC, reversed the anxiogenic effects of 8-OH-DPAT (5, 10, and 50 ng/rat). Intra-MPFC microinjection of 5HT(1B) receptor agonist, CGS-12066A (0.25, 0.5, and 1 µg/rat) significantly decreased OAT% and OAE%, without any change in locomotor activity, indicating an anxiogenic effect. However, injection of 5HT(1B) receptor antagonist, SB-224289 (0.5, 1, and 2 µg/rat) into the MPFC showed no significant effect. In conclusion, these findings suggest that 5HT(1A) and 5HT(1B) receptors of the MPFC region modulate anxiogenic-like behaviors in rats.

Dorsal hippocampal N-methyl-D-aspartate glutamatergic and δ-opioidergic systems modulate anxiety behaviors in rats in a noninteractive manner.

The present study aimed to investigate the effects of N-methyl-d-aspartate (NMDA)-type glutamate receptor agonist, NMDA, on anxiety-like behavior induced by δ-opioid receptor agents in rats, using the elevated plus maze instrument. The dorsal hippocampus (CA1) is known to play an important role in anxiety formation and modulation. Bilateral administration of different doses of δ-opioid receptor agonist, [d-pen2,5] enkephalin acetate hydrate (1 µg/rat, 2 µg/rat, 5 µg/rat, and 10 µg/rat; 1 µL/rat; 0.5 µL/rat in each side), into CA1 area induced an anxiolytic-like effect, demonstrated by substantial increases in the percent of open arm time (OAT%) and percent of open arm entries (OAE%). Intra-CA1 injection of different doses of δ-opioid receptor antagonist, naltrindole hydrochloride (0.25 µg/rat, 0.5 µg/rat, 1 µg/rat, and 2 µg/rat), produced significant anxiogenic-like behavior. Furthermore, intra-CA1 administration of NMDA glutamate receptor agonist, NMDA (0.125 µg/rat, 0.25 µg/rat, 0.5 µg/rat, and 0.75 µg/rat), increased the OAT% and OAE%, indicating anxiolytic-like behavior. However, administration of different doses of NMDA glutamatergic antagonist, MK801 (0.125 µg/rat, 0.25 µg/rat, 0.5 µg/rat, and 1µg/rat), showed no significant effect on the OAT% but decreased the OAE% significantly. The ineffective dose of NMDA (0.125 µg/rat), when coadministered with enkephalin (1 µg/rat, 2 µg/rat, 5 µg/rat, and 10 µg/rat), did not decrease the anxiety behavior significantly. An effective dose of NMDA (0.5 µg/rat), in combination with different doses of naltrindole hydrochloride (0.25 µg/rat, 0.5 µg/rat, 1 µg/rat, and 2 µg/rat), demonstrated no significant interaction with the OAT%, OAE%, and locomotor activity. These results suggest that CA1 δ-opioid and NMDA glutamatergic systems modulate anxiety behaviors in a noninteractive manner.

Synthesis and analgesic effects of new pyrrole derivatives of phencyclidine in mice.

Phencyclidine (1-(1-phenylcyclohexyl)piperidine, CAS 956-90-1, PCP, I) and many of its analogues have shown some pharmacological effects. In this study, new pyrrole derivatives of I (1-(1-phenylcyclohexyl)pyrrole, II and 1-[1-(4-methylphenyl)(cyclohexyl)]pyrrole, III) and their intermediates were synthesized and the acute and chronic pains were examined on mice using tail immersion (as a model of acute thermal pain) and formalin (as a model of acute and chronic chemical pain) tests and the results were compared with the PCP and control groups. The results indicated that III generated higher analgesic effects in the tail immersion test compared to the PCP and control (dimethyl sulfoxide, DMSO) groups, demonstrating a marked and significant increase in tail immersion latency, but this effect was not observed for II in the dose of 1 mg/kg. The formalin test showed that III was effective in acute chemical pain (phase I, 0-5 min after injection), but was not effective for II at the same dosage compared to the PCP and control groups. Also chronic pain will be significantly attenuated by III but II was not effective as compared to the other groups. It is concluded that substitution of the aromatic pyrrole ring instead of piperidine in the PCP molecule will not be effective alone in tail immersion and formalin tests but the addition of a methyl group (with high electron donating and dipole moments) on the phenyl group plus substitution of the aromatic pyrrole ring can be effective in acute and chronic pain compared to the PCP and control groups.

Prenatal exposure to LPS leads to long-lasting physiological consequences in male offspring.

Growing evidence suggests that early life events are critical determinants for disorders later in life. According to a comprehensive number of epidemiological/animal studies, exposure to lipopolysaccharide, causes alteration in pro-inflammatory cytokine levels, hypothalamic-pituitary-adrenal functioning and the hormonal system which may contribute to behavioral and neurological injuries. In this study we investigated the effects of lipopolysaccharide administration on physiological parameters in pregnant dams and their male offspring aged 9 weeks. In gestational Day 10, pregnant mice were injected intrapritoneally with Salmonella enterica lipopolysaccharide to model prenatal exposure to infection. The following results were obtained for offspring from dams stressed during pregnancy: (a) reduced anxiety-related behavior in the elevated plus maze; (b) reduced food and water intake; (c) reduced body weight from birth up to postnatal Day 40. The observed data provide experimental evidence showing that prenatal stress can have complex and long-lasting physiological/behavioral consequences in offspring.

Dorsal hippocampal opioidergic system modulates anxiety-like behaviors in adult male Wistar rats.

AIMS: In the present study, we investigated the possible influence of the opioidergic system of the dorsal hippocampus on anxiety-like behaviors. METHODS: Elevated plus-maze, which is one of the methods used for testing anxiety, was used in the present study. Rats were anesthetized with ketamine and xylazine and special cannulas were inserted stereotaxically into the CA1 region of the dorsal hippocampus. After 1 week of recovery, the effects of intra-CA1 administration of morphine (0.25, 0.5, 1 and 2 µg/rat; 1 µl/rat; 0.5 µl/in each side), naloxone (2, 4, 6 and 8 µg/rat), enkephalin (1, 2, 5 and 10 µg/rat) and naltrindole (0.25, 0.5, 1 and 2 µg/rat) on percentage open arm time (%OAT) and percentage open arm entries (%OAE) were determined. RESULTS: Bilateral administration of morphine into CA1 decreases %OAT and %OAE, indicating an anxiogenic-like effect. Intra-CA1 injection of naloxone, an opioid receptor antagonist, increased both %OAT and %OAE, parameters of anxiolytic-like behavior. Bilateral administration of δ-opioid receptor agonist, [D-Pen(2,5) ]-enkephalin acetate hydrate into the CA1, induced an anxiolytic-like effect. Furthermore, intra-CA1 injection of δ-opioid receptor antagonist, naltrindole hydrochloride, increased anxiety-related behaviors. CONCLUSIONS: The results of the present study demonstrate that activation of µ-opioid receptors in this area produce an anxiogenic response while activation of δ-opioid receptors produces an anxiolytic response.

Synthesis and analgesic effects of 1-[1-(2-methylphenyl)(cyclohexyl)]-3-piperidinol as a new derivative of phencyclidine in mice.

Phencyclidine (1-(1-phenylcyclohexyl) piperidine, CAS 956-90-1, PCP, I) and its derivatives have shown many analgesic effects. In this research, a new derivative of PCP (1-[1-(2-methylphenyl) (cyclohexyl)l3-piperidinol, PD, II) was synthesized and its analgesic (acute and chronic pains) effects were examined on rats using tail immersion (as a model of acute thermal pain) and formalin (as a model of acute and chronic chemical pain) tests and the results are compared to PCP and control groups. The results indicated that II produces higher analgesic effects in the tail immersion test compared to the PCP and control groups, with a marked and significant increase in tail immersion latency for the doses 1, 5 and 10 mg/kg. The formalin test showed that PD (II) is not effective in acute chemical pain (phase I, 0-5 min after injection) in all doses but chronic pain (initial-phase II, 15-40 min after injection) is significantly attenuated by this compound compared to PCP and saline (control) in dosesof 5 and 10 mg/kg. It is concluded that II is effective in acute thermal (in all doses) and chronic (doses of 5 and 10 mg/kg) pains; however, it is not effective in acute chemical pain compared to PCP and control.

Antihyperglycemic and antihyperlipidemic effects of Ziziphus vulgaris L. on streptozocin-induced [corrected] diabetic adult male Wistar rats.

Herbal medicine and medical plants such as Ziziphus vulgaris L. are widely used for the treatment of diseases such as diabetes mellitus. We investigated the effects of water extracts of Ziziphus vulgaris L. fruit on serum glucose, triglycerides, LDL-cholesterol, HDL-cholesterol and activities of aminotransferase enzymes inreptozocin-induced diabetic adult male rats. Continuous supplementation of this water extract by gavage at doses of 0.25, 0.5, 1, 1.5 and 2 g/kg in 0.5 ml distilled water in diabetic rats resulted in a significant decrease of fasting blood glucose and LDL-cholesterol and triglyceride levels after 14 days. The levels of HDL-cholesterol and insulin, and activities of serum aminotransaminase enzymes, alanine aminotransferase and aspartate aminotransferase were not changed significantly in the extract-supplemented group compared to the control group.

Effect of intra-amygdala injection of nicotine and GABA receptor agents on anxiety-like behaviour in rats.

There is evidence that both cholinergic and GABAergic systems are involved in the neurobiology of anxiety. In the present study, we investigated the effects and interaction of nicotinic and GABAergic systems in the central amygdala of rats, using the elevated plus maze test of anxiety. Bilateral administration of nicotine (1 and 2 microg/rat; 1 microl/rat; 0.5 microl/rat in each side) into the central amygdala (intra-CeA) induced an anxiogenic-like effect, shown by specific decreases in the percentage of open-arm time (%OAT) and percentage of open arm entries (%OAE). Intra-CeA injection of mecamylamine, a selective nicotine acetylcholine receptor antagonist (20, 30 and 50 ng/rat; 1 microl/rat; 0.5 microl/rat in each side) produced significant anxiolytic-like behaviour. The intra-CeA injection of the GABAA receptor agonist muscimol (0.25, 0.5 and 0.75 microg/rat; 1 microl/rat; 0.5 microl/rat in each side) decreased %OAT and %OAE, indicating anxiogenic-like behaviour. However, intra-CeA administration of the GABAA receptor antagonist bicuculline (0.25, 0.5 and 1 microg/rat; 1 microl/rat; 0.5 microl/rat in each side) produced significant anxiolytic-like behaviour. Nicotine in a subeffective dose (0.25 microg/rat) when co-administered with muscimol did not significantly increase the anxiety behaviour. An effective dose of nicotine (2 microg/rat) in combination with bicuculline (0.25, 0.5 and 1 microg/rat) had no interaction on %OAT, %OAE and locomotor activity. It can be concluded that in the central amygdala, the GABAergic system is not involved in the anxiogenic response to nicotine.