Evaluation of the in vivo anti-inflammatory activity of a flavonoid glycoside from Boldoa purpurascens

The anti-inflammatory effect of 4′,5-dihydroxy-6,7-methylenedioxyflavonol 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranoside, a constituent of the leaves of Boldoa purpurascens Cav. (Nyctaginaceae), was evaluated for its anti-inflammatory activity in the dextran 1% induced rat paw oedema model (acute inflammation) and the cotton pellet induced granuloma rat model (chronic inflammation). Flavonoid glycoside at doses of 2.5, 5 and 10 mg/kg, indomethacin at a dose of 7 mg/kg and the vehicle were administered orally. The compound showed significant anti-inflammatory activity in the acute phase in a dose dependent manner, most notably at the highest test dose 10 mg/kg. Also in the cotton pellet induced granuloma model, the compound showed a dose-dependent anti-inflammatory activity, with the highest effect at 10 mg/kg. In both assays, the test compound was more active than indomethacin tested at 7 mg/kg.     

Synthesis and analgesic effects of novel β2-tryptophan hexapeptide analogs

Aiming to develop more potent analgesic substances a new series of hexapeptides containing β²-tryptophan analogues was synthesized. The Trp in position 4 and 5, respectively in Ac-Arg-Phe-Met-Trp-Met-Lys-NH₂ (opioid receptor antagonist) and Ac-Arg-Tyr-Tyr-Arg-Trp-Lys-NH₂ (highly potent and selective NOP-receptor agonist) was substituted by the (S)-2-(1-methyl-1H-indol-3-yl)propionic residue or the (S)-2-(5-methoxy-1H-indol-3-yl)propionic residue. The analgesic effect of the four newly synthesized compounds has been evaluated in male Wistar rats by PP- and HP tests and compared to the native templates. Further estimation of the mechanisms of action of each compound was achieved using specific antagonists—naloxone for opioid and JTC801 for the NOP receptor. Replacement of Trp with β²-tryptophan analogues in 4th position (Ac-Arg-Phe-Met-Trp-Met-Lys-NH₂) led to increased and longer lasting analgesic effect. The results obtained permit us to assume that both opioid and NOP receptors take part in the newly synthesized compounds analgesic effects.     

Design,synthesis, evaluation,and molecular docking of ursolic acid derivatives containing a nitrogen heterocycle as anti-inflammatory agents

Ursolic acid derivatives containing oxadiazole, triazolone, and piperazine moieties were synthesized in an attempt to develop potent anti-inflammatory agents. Structures of the synthesized compounds were elucidated by ¹H NMR, ¹³C NMR, and HRMS. Most of the synthesized compounds showed pronounced anti-inflammatory effects at 100?mg/kg. In particular, compound 11b, which displayed the most potent anti-inflammatory activity of all of the compounds prepared, with 69.76% inhibition after intraperitoneal administration, was more potent than the reference drugs indomethacin and ibuprofen. The cytotoxicity of the compounds was also assessed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and no compounds showed any appreciable cytotoxic activity (IC₅₀ >100?μmol/L). Furthermore, molecular docking studies of the synthesized compounds were performed to rationalize the obtained biological results. Overall, the results indicate that compound 11b could be a therapeutic candidate for the treatment of inflammation.     

Buprenorphine‐elicited alteration of adenylate cyclase activity in human embryonic kidney 293 cells coexpressing κ‐, μ‐opioid and nociceptin receptors

Buprenorphine, a maintenance drug for heroin addicts, exerts its pharmacological function via κ‐ (KOP), μ‐opioid (MOP) and nociceptin/opioid receptor‐like 1 (NOP) receptors. Previously, we investigated its effects in an in vitro model expressing human MOP and NOP receptors individually or simultaneously (MOP, NOP, and MOP+NOP) in human embryonic kidney 293 cells. Here, we expanded this cell model by expressing human KOP, MOP and NOP receptors individually or simultaneously (KOP, KOP+MOP, KOP+NOP and KOP+MOP+NOP). Radioligand binding with tritium‐labelled diprenorphine confirmed the expression of KOP receptors. Immunoblotting and immunocytochemistry indicated that the expressed KOP, MOP and NOP receptors are N‐linked glycoproteins and colocalized in cytoplasmic compartments. Acute application of the opioid receptor agonists— U‐69593, DAMGO and nociceptin— inhibited adenylate cyclase (AC) activity in cells expressing KOP, MOP and NOP receptors respectively. Buprenorphine, when applied acutely, inhibited AC activity to ~90% in cells expressing KOP+MOP+NOP receptors. Chronic exposure to buprenorphine induced concentration‐dependent AC superactivation in cells expressing KOP+NOP receptors, and the level of this superactivation was even higher in KOP+MOP+NOP‐expressing cells. Our study demonstrated that MOP receptor could enhance AC regulation in the presence of coexpressed KOP and NOP receptors, and NOP receptor is essential for concentration‐dependent AC superactivation elicited by chronic buprenorphine exposure.     

Antinociceptive action of NOP and opioid receptor agonists in the mouse orofacial formalin test

Nociceptin/orphanin FQ (N/OFQ) modulates several biological functions, including pain transmission via selective activation of a specific receptor named NOP. The aim of this study was the investigation of the antinociceptive properties of NOP agonists and their interaction with opioids in the trigeminal territory. The orofacial formalin (OFF) test in mice was used to investigate the antinociceptive potential associated to the activation of NOP and opioid receptors. Mice subjected to OFF test displayed the typical biphasic nociceptive response and sensitivity to opioid and NSAID drugs. Mice knockout for the NOP gene displayed a robust pronociceptive phenotype. The NOP selective agonist Ro 65-6570 (0.1–1 mg kg⁻¹) and morphine (0.1–10 mg kg⁻¹) elicited dose dependent antinociceptive effects in the OFF with the alkaloid showing larger effects; the isobologram analysis of their actions demonstrated an additive type of interaction. The mixed NOP/opioid receptor agonist cebranopadol elicited potent (0.01–0.1 mg kg⁻¹) and robust antinociceptive effects. In the investigated dose range, all drugs did not modify the motor performance of the mice in the rotarod test. Collectively the results of this study demonstrated that selective NOP agonists and particularly mixed NOP/opioid agonists are worthy of development as innovative drugs to treat painful conditions of the trigeminal territory.     

Synthesis and pharmacological evaluation of 6-naltrexamine analogs for alcohol cessation

A series of substituted aryl amide derivatives of 6-naltrexamine, 3 designed to be metabolically stable were synthesized and used to characterize the structural requirements for their potency to binding and functional activity of human mu (μ), delta (δ) and kappa (κ) opioid and nociceptin (NOP) receptors. Binding assays showed that 4–10 had subnanomolar K_i values for μ and κ opioid receptors. Functional assays for stimulation of [³⁵S]GTPγS binding showed that several compounds acted as partial or inverse agonists and antagonists of the μ and δ, κ opioid or NOP receptors. The compounds showed considerable stability in the presence of rat, mouse or human liver preparations and NADPH. The inhibitory activity on the functional activity of human cytochrome P450s was examined to determine any potential inhibition by 4–9. Only modest inhibition of CYP3A4, CYP2C9 and CYP2C19 was observed for a few of the analogs. As a representative example, radiolabeled 6 was examined in vivo and showed reasonable brain penetration. The inhibition of ethanol self-administration in rats trained to self-administer a 10% (w/v) ethanol solution, utilizing operant techniques showed 5–8 to have very potent efficacy (ED₅₀ values 19–50 μg/kg).     

Arsenic(V) biosorption by charred orange peel in aqueous environments

Biosorption efficiency of natural orange peel (NOP) and charred orange peel (COP) was examined for the immobilization of arsenate (As(V)) in aqueous environments using batch sorption experiments. Sorption experiments were carried out as a function of pH, time, initial As(V) concentration and biosorbent dose, using NOP and COP (pretreated with sulfuric acid). Arsenate sorption was found to be maximum at pH 6.5, with higher As(V) removal percentage (98%) by COP than NOP (68%) at 4 g L^?1 optimum biosorbent dose. Sorption isotherm data exhibited a higher As(V) sorption (60.9 mg g^?1) for COP than NOP (32.7 mg g^?1). Langmuir model provided the best fit to describe As(V) sorption. Fourier transform infrared spectroscopy and scanning electron microscopy combined with energy dispersive X-ray spectroscopy analyses revealed that the –OH, –COOH, and –N-H surface functional groups were involved in As(V) biosorption and the meso- to micro-porous structure of COP sequestered significantly (2-times) higher As(V) than NOP, respectively. Arsenate desorption from COP was found to be lower (10%) than NOP (26%) up to the third regeneration cycle. The results highlight that this method has a great potential to produce unique ‘charred’ materials from the widely available biowastes, with enhanced As(V) sorption properties.     

Design,synthesis, anti-inflammatory activity,and molecular docking studies of perimidine derivatives containing triazole

We report here the design, synthesis, and anti-inflammatory activities of a series of perimidine derivatives containing triazole (5a–s). The chemical structures of the synthesized compounds have been assigned on the basis of IR, ¹H NMR, ¹³C NMR, and HRMS spectral analyses. The anti-inflammatory properties of the synthesized perimidine derivatives were evaluated in a lipopolysaccharide (LPS)-stimulated inflammation model. Among the tested compounds, compound 7-(3-methylbenzyl)-7H-[1,2,4]triazolo[4,3-a]perimidine (hereafter referred to as 5h) and compound 7-(2-fluorobenzyl)-7H-[1,2,4]triazolo[4,3-a]perimidine (hereafter referred to as 5n) caused a reduction in the levels of the pro-inflammatory cytokines—tumor necrosis factor (TNF)-α and interleukin (IL)-6—in RAW264.7 cells. The anti-inflammatory potential of compounds 5h and 5n was also evaluated in vivo in a xylene-induced ear inflammation model. Compound 5n showed the most potent anti-inflammatory activity with an inhibition of 49.26% at a dose of 50 mg/kg. This activity is more potent than that of the reference drug ibuprofen (28.13%), and slightly less than that of indometacin (49.36%). To further elucidate the mechanisms underlying these inhibitory effects, LPS-induced nuclear factor-κB (NF-κB) activation and mitogen-activated protein kinase (MAPK) phosphorylation were studied. The results of western blotting showed that the extract obtained from compound 5n inhibited NF-κB (p65) activation and MAPK (extracellular signal-regulated kinase (ERK) and p38) phosphorylation in a dose-dependent manner. Moreover, the results of a docking study of compound 5n into the COX-2 binding site revealed that its mechanism was possibly similar to that of naproxen, a COX-2 inhibitor. The effect of compound 5n on COX-2 antibody was showed it could significantly inhibit COX-2 activity.     

Boron Affects Immune Function Through Modulation of Splenic T Lymphocyte Subsets,Cytokine Secretion,and Lymphocyte Proliferation and Apoptosis in Rats

This study demonstrated the mechanisms of boron effects in a rat model and provided a scientific basis for the rational of boron use. These findings were achieved by investigating the effects of boron (10, 20, 40, 80, 160, 320, and 640 mg/L in drinking water or 1.5, 3, 6, 12, 24, 48, and 96 mg/kg BW) on rat serum immunoglobulins (IgGs), splenic cytokines, lymphocyte subsets, as well as on lymphocyte proliferation and apoptosis. Addition of 20 (3) and 40 (6) mg/L (mg/kg BW) of boron to drinking water significantly increased rat serum IgG concentrations, splenic IFN-γ and IL-4 expression as well as the number of splenic CD3⁺, CD4⁺ and proliferating cell nuclear antigen (PCNA)⁺ cells. Supplementation of drinking water with 40 mg/L (6 mg/kg BW) boron also markedly increased splenic IL-2 expression and the CD4⁺/CD8⁺ cell ratio and reduced splenic CD8⁺ cell number. Supplementation with 80 mg/L (12 mg/kg BW) boron significantly increased CD3⁺ and PCNA⁺ cell numbers (P < 0.05) and decreased the IL-10 expression in the spleen. Addition of 320 (48) and 640 (96) mg/L (mg/kg BW) boron markedly reduced the serum IgG concentrations; splenic IL-2 and IL-10 expression; the number of CD3⁺, CD4⁺ and PCNA⁺ cells; and increased the number of splenic CD8⁺ and caspase-3⁺ cells and promoted caspase-3 expression in CD3⁺ cells. In conclusion, these findings suggest that the supplementation of rat drinking water with 20(3) and 40(6) mg/L (mg/kg BW) boron can markedly enhance humoral and cellular immune functions, while boron concentrations above 320 mg/L (48 mg/kg BW) can have an inhibitory effect or even toxicity on immune functions. These results exhibit a U-shaped response characteristic of low and high doses of boron supplementation on immune function and imply that proper boron supplementation in food for humans and animals could be used as an immunity regulator.     

Role of pertussis toxin-sensitive G-protein, K+ channels, and voltage-gated Ca2+ channels in the antinociceptive effect of inosine

Inosine is the first metabolite of adenosine. It exerts an antinociceptive effect by activating the adenosine A₁ and A_2A receptors. We have previously demonstrated that inosine exhibits antinociceptive properties in acute and chronic mice models of nociception. The aim of this study was to investigate the involvement of pertussis toxin-sensitive G-protein-coupled receptors, as well as K⁺ and Ca²⁺ channels, in the antinociception promoted by inosine in the formalin test. Mice were pretreated with pertussis toxin (2.5 μg/site, i.t., an inactivator of G_i/0 protein); after 7 days, they received inosine (10 mg/kg, i.p.) or morphine (2.5 mg/kg, s.c., used as positive control) immediately before the formalin test. Another group of animals received tetraethylammonium (TEA) or 4-aminopyridine (4-AP) (1 μg/site, i.t., a non-specific voltage-gated K⁺ channel blockers), apamin (50 ng/site, i.t., a small conductance Ca²⁺-activated K⁺ channel blocker), charybdotoxin (250 pg/site, i.t., a large-conductance Ca²⁺-activated K⁺ channel blocker), glibenclamide (100 μg/site, i.t., an ATP-sensitive K⁺ channel blocker) or CaCl₂ (200 nmol/site, i.t.). Afterwards, the mice received inosine (10 mg/kg, i.p.), diclofenac (10 mg/kg, i.p., a positive control), or morphine (2.5 mg/kg, s.c., a positive control) immediately before the formalin test. The antinociceptive effect of inosine was reversed by the pre-administration of pertussis toxin (2.5 μg/site, i.t.), TEA, 4-aminopyridine, charybdotoxin, glibenclamide, and CaCl₂, but not apamin. Further, all K⁺ channel blockers and CaCl₂ reversed the antinociception induced by diclofenac and morphine, respectively. Taken together, these data suggest that the antinociceptive effect of inosine is mediated, in part, by pertussis toxin-sensitive G-protein coupled receptors and the subsequent activation of voltage gated K⁺ channel, large conductance Ca²⁺-activated and ATP-sensitive K⁺ channels or inactivation of voltage-gated Ca²⁺ channels. Finally, small conductance Ca²⁺-activated K⁺ channels are not involved in the antinociceptive effect of inosine.     

Effect of novel nociceptin/orphanin FQ-NOP receptor ligands on ethanol drinking in alcohol-preferring msP rats

Activation of the NOP receptor by the endogenous ligand nociceptin/orphanin FQ (N/OFQ) reduces alcohol consumption in genetically selected alcohol-preferring Marchigian Sardinian (msP) rats. The present study evaluated the effect of three newly synthesized peptidergic and one brain-penetrating heterocyclic NOP receptor agonists on alcohol drinking in the two bottle choice paradigm. MsP rats were intracerebroventricularly (ICV) injected with the NOP receptor agonists OS-462 (0.5 and 1.0 μg), UFP-102 (0.25 and 1.0 μg) or UFP-112 (0.01 and 0.05 μg), or with Ro 64-6198 (0.3 and 1.0 mg/kg) given intraperitoneally (i.p.) and tested for 10% alcohol consumption. Results showed decreased alcohol consumption after treatment with all three peptidergic NOP receptor agonists (OS-462, UFP-102 and UFP-112). OS-462 (at the 1.0 μg dose) and UFP-102 (at the 0.25 μg dose) induced a significant increase in food intake as well. Surprisingly, Ro 64-6198 was ineffective at the 0.3 mg/kg dose, whereas it increased ethanol and food consumption at the 1.0 mg/kg dose. Pre-treatment with the selective μ-receptor antagonist naloxone (0.5 mg/kg, i.p.) reduced these effects of 1.0 mg/kg of Ro 64-6198. These findings confirm that activation of brain NOP receptors reduces alcohol drinking in msP rats and demonstrate that OS-462, UFP-102 and UFP-112 act as potent NOP receptor agonists. On the other hand, Ro 64-6198 increased alcohol drinking, an effect probably induced by a residual agonist activity of this compound at μ-opioid receptors. Overall, the results indicate that OS-462, UFP-102 and UFP-112 may represent valuable pharmacological tools to investigate the functional role of the brain N/OFQ system.     

Effects of Pinus brutia bark extract and Pycnogenol® in a rat model of carrageenan induced inflammation

The present study was conducted to explore the anti-inflammatory activities of Pinus brutia bark extract and Pycnogenol^® in a rat model of carrageenan-induced inflammation. Firstly, the compositions of both samples were determined using HPLC. Then, carrageenan-induced paw edema was used to assess anti-inflammatory activity in mice. Paw volume was measured before and 1, 2, 3, 4, 5 and 6 h after the injection of carrageenan. Intraperitoneal administration of both the extract and Pycnogenol^® inhibited paw swelling dose-dependently at 2, 3, 4, 5 and 6 h after carrageenan injection. Both samples exhibited significant anti-inflammatory activities at doses of 75 and 100 mg/kg body wt. between 2 and 4 hours after administration (p<0.05), respectively. Additionally, P. brutia bark extract showed significantly better activity at doses of 75 and 100 mg/kg body wt. than indomethacine at the dose of 10 mg/kg body wt. (p<0.05). No acute toxicity was identified in intraplantar injection of the extract at a dose of 2000 mg/kg body wt.. Therefore, P. brutia bark extract possessing 3.3-fold more total catechins and 9.8-fold more taxifolin than Pycnogenol^® can be utilized as an anti-inflammatory agent.     

Anti-inflammatuar and anti-oxidative effects of Nigella sativa L.: 18FDG-PET imaging of inflammation

Inflammation has an important role in many diseases such as cystic fibrosis, allergies and cancer. The free radicals produced during inflammation, can induce gene mutations and posttranslational modifications of cancer related proteins. Nigella sativa L. (N. sativa) is herbaceous plant and commonly used as a natural food. It has many pharmacological effects including antibacterial, antifungal, antitumor, analgesic, antipyretic activity. The aim of this study was to investigate the anti-inflammatuar and anti-oxidant activity of N. sativa in acute inflammation. Thus we used the experimental lipopolysaccharides (LPS)-induced model. Intraperitoneal LPS 1 mg/kg was administered to groups. N. sativa (500 mg/kg) and essential oil (5 ml/kg) were given orally to treatment groups, after 24-h of intraperitoneal LPS-injection. To determine the lung inflammation, ¹⁸F-fluoro-deoxy-d-glucose (0.8 ml/kg) was administrated under the anesthesia before the 1 h of PET-scanning. After the FDG-PET, samples were collected. Lung and liver ¹⁸F-FDG-uptake was calculated. Serum AST, ALT, LDH and hcCRP levels were determined and liver, lung and erythrocyte SOD, MDA and CAT levels were measured. Liver and lung NO and DNA fragmentation levels were determined. MDA levels were decreased in treated inflammation groups whereas increased in untreated inflammation group. SOD and CAT activities in untreated inflammation group were significantly lower. According to the control group, increased AST and ALT levels were found in untreated inflammation group. ¹⁸F-FDG uptake of inflammation groups were increased when compare the control group. We found increased ¹⁸F-FDG uptake, DNA fragmentation and NO levels in LPS-induced inflammation groups. We conclude that, in LPS-induced inflammation, N. sativa have therapeutic and anti-oxidant effects.     

Quantitative study of [Tyr10]nociceptin/orphanin FQ (1-11) at NOP receptors in rat periaqueductal gray and expressed NOP receptors in HEK293 cells

AimThe nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor was reported to be functionally heterogeneous. We investigated if [Tyr¹⁰]N/OFQ(1-11), a peptide ligand reported to selectively bind to the high affinity site of ¹²⁵I-[Tyr¹⁴]N/OFQ in rodent brains, can be a tool for revealing the NOP receptor heterogeneity. We have previously founded an NOP receptor subset insensitive to Ro 64-6198 and (+)-5a Compound, two non-peptide NOP agonists, in rat ventrolateral periaqueductal gray (vlPAG) neurons. Here, we examined if [Tyr¹⁰]N/OFQ(1-11) differentiated (+)-5a Compound-sensitive and -insensitive vlPAG neurons. Certain mu-opioid (MOP) receptor ligands highly competing with [Tyr¹⁰]N/OFQ(1-11) in binding studies also showed high affinity at expressed heteromeric NOP–MOP receptors. We also examined if [Tyr¹⁰]N/OFQ(1-11) distinguished heteromeric NOP–MOP receptors from homomeric NOP receptors.Main methodsThe NOP receptor activity was evaluated by G-protein coupled inwardly rectifying potassium (GIRK) currents in rat vlPAG slices, and by inhibition of cAMP accumulation in HEK293 cells expressing NOP receptors or co-expressing NOP and MOP receptors.Key findingsIn vlPAG neurons, [Tyr¹⁰]N/OFQ(1-11), like N/OFQ, induced GIRK currents through NOP receptors. It was less potent (EC₅₀: 8.98 μM) but equi-efficacious as N/OFQ. [Tyr¹⁰]N/OFQ(1-11) displayed different pharmacological profiles as (+)-5a Compound, and was effective in both (+)-5a Compound-sensitive and -insensitive neurons. In NOP-expressing HEK293 cells and NOP- and MOP-co-expressing cells, [Tyr¹⁰]N/OFQ(1-11) displayed similar concentration–response curves in decreasing cAMP accumulation.Significance[Tyr¹⁰]N/OFQ(1-11) is an NOP full agonist and less potent than N/OFQ. However, it can neither reveal the functional heterogeneity of NOP receptors in vlPAG neurons nor differentiate heteromeric NOP–MOP and homomeric NOP receptors.     

Effects of Pinus brutia bark extract and Pycnogenol® in a rat model of carrageenan induced inflammation

The present study was conducted to explore the anti-inflammatory activities of Pinus brutia bark extract and Pycnogenol^® in a rat model of carrageenan-induced inflammation. Firstly, the compositions of both samples were determined using HPLC. Then, carrageenan-induced paw edema was used to assess anti-inflammatory activity in mice. Paw volume was measured before and 1, 2, 3, 4, 5 and 6 h after the injection of carrageenan. Intraperitoneal administration of both the extract and Pycnogenol^® inhibited paw swelling dose-dependently at 2, 3, 4, 5 and 6 h after carrageenan injection. Both samples exhibited significant anti-inflammatory activities at doses of 75 and 100 mg/kg body wt. between 2 and 4 hours after administration (p<0.05), respectively. Additionally, P. brutia bark extract showed significantly better activity at doses of 75 and 100 mg/kg body wt. than indomethacine at the dose of 10 mg/kg body wt. (p<0.05). No acute toxicity was identified in intraplantar injection of the extract at a dose of 2000 mg/kg body wt.. Therefore, P. brutia bark extract possessing 3.3-fold more total catechins and 9.8-fold more taxifolin than Pycnogenol^® can be utilized as an anti-inflammatory agent.     

Toxicity of Chemically Spiked Sediment to the Carpet Shell Clam Ruditapes decussatus Embryos and Larvae

The objective of this research was to assess the toxicity of sediment contaminated with cadmium, DDT, chlorpyrifos, and fluoranthene to embryos and larvae of the European clam Ruditapes decussatus, exposed to two sediment fractions, the whole sediment and elutriate. The percentages of abnormal D-shaped larvae and larval mortality have been investigated. The median effective concentration (EC50) values, reducing 50% of the percentage of D-shaped larvae, in whole sediments and elutriates were, respectively, 1.17 mg/kg and 417.1 μgl^?1 (3.71 μM) for cadmium, 1.66 mg/kg and 97.8 μgl^?1 (0.48 μM) for fluoranthene, 1.71 mg/kg and 384.8 μgl^?1 (1.08 μM) for DDT, and 0.96 mg/kg and 339.5 μgl^?1 (0.96 μM) for chlorpyrifos. The 96h-median lethal concentrations (LC50) reducing larval survival by 50% were 4.04 mg/kg 654.3 μgl^?1 (5.82 μM) for cadmium, 17.41 mg/kg 8666.6 μgl^?1 (42.84 μM) for fluoranthene, 3.93 mg/kg and 457.4 μgl^?1 (1.29 μM) for DDT, and 2.53 mg/kg and 308.06 μgl^?1 (0.87 μM) for chlorpyrifos. Based on EC₅₀ and LC₅₀ comparisons to toxicity data for other marine species, these findings suggest that the R. decussatus embryotoxicity and larvae mortality bioassay were among the most sensitive tools for sediment quality assessment.     

Design,synthesis and evaluation of [3H]PF-7191, a highly specific nociceptin opioid peptide (NOP) receptor radiotracer for in vivo receptor occupancy (RO) studies

Herein we report the identification of (+)-N-(2-((1H-pyrazol-1-yl)methyl)-3-((1R,3r,5S)-6′-fluoro-8-azaspiro[bicyclo[3.2.1]octane-3,1′-isochroman]-8-yl)propyl)-N-[³H]-methylacetamide {[³H]PF-7191 [(+)-11]} as a promising radiotracer for the nociceptin opioid peptide (NOP) receptor. (+)-11 demonstrated high NOP binding affinity (K_i = 0.1 nM), excellent selectivity over other opioid receptors (>1000×) and good brain permeability in rats (C_b,u/C_p,u = 0.29). Subsequent characterization of [³H](+)-11 showed a high level of specific binding and a brain bio-distribution pattern consistent with known NOP receptor expression. Furthermore, the in vivo brain binding of [³H](+)-11 in rats was inhibited by a selective NOP receptor antagonist in a dose–responsive manner. This overall favorable profile indicated that [³H](+)-11 is a robust radiotracer for pre-clinical in vivo receptor occupancy (RO) measurements and a possible substrate for carbon-11 labeling for positron emission tomography (PET) imaging in higher species.     

Effectiveness of prostaglandin F2α in restoration of HMG-HCG induced ovulation in indomethacin-treated rhesus monkeys

Six mature female rhesus monkeys were treated with HMG-HCG in control cycles at doses adjusted to induce ovulation while avoiding superovulation. Occurrence of ovulation was determined by observation of fresh ovulation points at laparotomy 48 to 120 hours following HCG. In subsequent cycles animals were treated with indomethacin (treatment days 4 through 10) together with the established dose of HMG_HCG. In 8 cycles indomethacin 5 mg/kg was given i.m. once daily; in 9 cycles 10 mg/kg i.m. was administered in 2 divided doses. Following this, PGF_2^α (3 mg t.i.d. s.c.) was administered for 3 days together with indomethacin 10 mg/kg and HMG-HCG, beginning on the day prior to HCG. Determinations of progesterone were performed by RIA on treatment days 4, 7, 10, and 11. Eleven of the 13 control cycles were ovulatory. With indomethacin 5 mg/kg/day, 5 of 8 cycles were ovulatory but ovulation was delayed in 2 instances. Of 9 cycles using indomethacin 10 mg/kg/day only 1 was ovulatory. When PGF_2^α was administered in subsequent cycles along with indomethacin (10 mg/kg) and HMG-HCG, ovulation occurred in 13 of 19 cycles. These data suggest that local ovarian PGF_2^α may be essential in the mechanics of follicle rupture in gonadotropin-treated rhesus monkeys.     

The novel nociceptin/orphanin FQ receptor antagonist Trap‐101 alleviates experimental parkinsonism through inhibition of the nigro‐thalamic pathway: positive interaction with L‐DOPA

In this study we investigated whether the recently discovered antagonist of the nociceptin/orphanin FQ (N/OFQ) opioid peptide (NOP) receptor, 1‐[1‐(cyclooctylmethyl)‐1,2,3,6‐tetrahydro‐5‐(hydroxymethyl)‐4‐pyridinyl]‐3‐ethyl‐1,3‐dihydro‐2H‐benzimidazol‐2‐one (Trap‐101) changed motor activity in naïve rats and mice, and alleviated parkinsonism in 6‐hydroxydopamine hemilesioned rats. In naïve rats, Trap‐101 stimulated motor activity at 10 mg/Kg and inhibited it at 30 mg/Kg. Such dual action was also observed in wild‐type but not NOP receptor knockout mice suggesting specific involvement of NOP receptors. Trap‐101 alleviated akinesia/bradykinesia and improved overall gait ability in hemiparkinsonian rats, being effective starting at 1 mg/Kg and without worsening motor deficit at 30 mg/Kg. To investigate the circuitry involved in the Trap‐101 action, behavioral tests were performed in rats undergoing microdialysis. The anti‐akinetic/anti‐bradykinetic effects of Trap‐101, given systemically (10 mg/Kg) or perfused in substantia nigra reticulata (10 μM), were associated with reduced glutamate and enhanced GABA release in substantia nigra, and reduced GABA release in ipsilateral ventro‐medial thalamus. When combined with ineffective doses of l ‐DOPA (0.1 mg/Kg), Trap‐101 evoked larger neurochemical and behavioral responses. These data show that Trap‐101 is an effective NOP receptor antagonist in vivo and confirm that NOP receptor antagonists alleviate parkinsonism through blockade of nigral NOP receptors and impairment of nigro‐thalamic transmission.