Effect of calcium chloride on the self-ignition behaviours of coal using hot-plate test

Fuel ◽  
2021 ◽  
Vol 304 ◽  
pp. 121451
Author(s):  
Bei Li ◽  
Hong-peng Lv ◽  
Jun Deng ◽  
Li-li Ye ◽  
Wei Gao ◽  
...  
2020 ◽  
Vol 15 (3) ◽  
pp. 205-214
Author(s):  
Manzumeh-Shamsi Meymandi ◽  
Gholamreza Sepehri ◽  
Amirhossein Moslemizadeh ◽  
Seyyed Sajjad Vakili Shahrbabaki

Background: Prenatal antiepileptic drug exposure could demonstrate both congenital malformations and behavioral impairments in offspring. Objective: This study was performed to assess the effects of prenatal exposure to pregabalin (PGB) on pain response, anxiety, motor activity and some behavior of adult offspring rats. Methods: Pregnant Wistar rats received PGB (7.5, 15 and 30 mg/kg/ip) during embryonic days 9.5- 15.5. The pain response, anxiety-like behaviors, locomotor activity, motor balance and coordination and anhedonia of adult offspring were examined by tail-flick and hot plate test, open field test, elevated plus maze (EPM), beam balance test and sucrose preference test in their 60th day of life, respectively. Results: Prenatal exposure to PGB revealed significant dose-dependent reduction in pain sensitivity (increase in pain latency response) in the hot plate test, especially in females, while anxiety-like behavior assessed in EPM and open field significantly reduced in males. In the open field, locomotor activity reduced significantly after exposure to PGB 30 mg/kg and motor coordination decreased dose-dependently, especially in males. Anhedonia, as an indication of sucrose preference or pleasure response, was not changed. Conclusion: These findings suggest that prenatal PGB exposure could be associated with significant changes in pain response, anxiety, locomotor activity and coordination in adult offspring rats.


2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Akinyinka O. Alabi ◽  
Abayomi M. Ajayi ◽  
Osarume Omorogbe ◽  
Solomon Umukoro

Abstract Background To investigate the antinociceptive and anti-inflammatory activities of aqueous extract of a blended mixture of dried leaves of Ocimum gratissimum and Psidium guajava, a traditional analgesic drug polyherbal (TADP) used as a remedy for pain-related conditions. Methods Antinociceptive activity of TADP (100, 200 and 400 mg/kg) was evaluated in the hot plate test and acetic acid-induced nociception in mice while the anti-inflammatory was evaluated in carrageenan-induced paw oedema in rats. Levels of nitrite, myeloperoxidase, glutathione and malondialdehyde were assayed in carrageenan-induced paw tissue. Results TADP (200 and 400 mg/kg) significantly prolong the latency time in the hot-plate test. TADP (100–400 mg/kg) produced a dose-dependent significant inhibition of the acetic-acid induced abdominal constriction. The antinociceptive activity of TADP in the presence of naloxone and atropine was not reversed whereas yohimbine and glibenclamide significantly reversed it. TADP (100, 200 and 400 mg/kg) significantly reduced the swelling in the carrageenan-induced oedema model and also produced a reduction in the nitrite and myeloperoxidase level. TADP (400 mg/kg) significantly reduced malondialdehyde concentration and increase glutathione level in the carrageenan-induced rat paw. TADP significantly decrease the number of cellular infiltrates in the histopathological assessment. Conclusion These results indicate that polyherbal product containing blended leaves of Ocimum gratissimum and Psidium guajava possess antinociceptive and anti-inflammatory properties, hence represents a promising alternative remedy in inflammation-induced pain.


2021 ◽  
Vol 17 ◽  
pp. 174480692199262
Author(s):  
Ken Iwata ◽  
Yukio Takamatsu ◽  
Nagafumi Doi ◽  
Kazutaka Ikeda

Electroconvulsive therapy (ECT) has been applied for chronic pain for decades. The amounts of opioids to treat pain are sometimes reduced after a series of ECT. The effect of ECT on morphine-induced analgesia and its mechanism underlying the reduction of morphine requirement has yet to be clarified. Therefore, we administered electroconvulsive shocks (ECS) to mice and investigated the antinociceptive effect of morphine in a hot plate test. We examined the expression level of µ-opioid receptor in the thalami of mice 25 h after administration of ECS compared to the thalami of mice without ECS administration using western blotting. ECS disturbed the development of a decrease in the percentage of maximal possible effect (%MPE), which was observed 24 h after a morphine injection, when ECS was applied 25, 23, 21, and 12 h before the second administration of morphine. We also examined the effect of ECS on the dose-response curve of %MPE to morphine-antinociception. Twenty-five hours after ECS, the dose-response curve was shifted to the left, and the EC50 of morphine given to ECS-pretreated mice decreased by 30.1% compared to the mice that were not pretreated with ECS. We also found that the expression level of µ-opioid receptors was significantly increased after ECS administration. These results confirm previous clinical reports showing that ECT decreased the required dose of opioids in neuropathic pain patients and suggest the hypothesis that this effect of ECT works through the thalamus.


2018 ◽  
Vol 3 (2) ◽  
pp. 13 ◽  
Author(s):  
AA Spasov ◽  
OY Grechko ◽  
DM Shtareva ◽  
AI Raschenko ◽  
Natalia Eliseeva ◽  
...  

Introduction: Opioid analgesics are the most efficient and widely used drugs for the management of moderate to severe pain. However, side effects associated with mu receptor activation, such as respiratory depression, tolerance and physical dependence severely limit their clinical application. Currently, the kappa-opioid system is the most attractive in terms of the clinical problem of pain, because kappa-agonists do not cause euphoria and physical dependence. The purpose of this study was to evaluate the antinociceptive effect of the novel compound - RU-1205. Methods: The analgesic activity of RU-1205 was studied on nociceptive models that characterize the central and peripheral pathways of pain sensitivity (hot plate test, electrically induced vocalisation, formalin test, writhing test). Results: RU-1205 exhibited highly potent antinociceptive effects in rodent models of acute pain with ED50 values of 0.002 - 0.49 mg /kg. Pretreatment with the κ-opioid receptor antagonist norBinaltorphimine significantly attenuated the analgesic activity of investigated substance in a hot plate test. Conclusions: It was established that the compound shows a significant dose-dependent central and peripheral analgesic effect. It was assumed kappa-opioidergic mechanism of analgesic effect of RU-1205.


2010 ◽  
Vol 9 (3) ◽  
pp. 28
Author(s):  
Sh. M. Al-khazrji , and I. K. Khalil

The present study was aimed to investigate the analgesic effects of the aqueous extract of Artemisia herba alba Arial part in rats and mice ( AEAHA ). The AEAHA (400- 700 mg/kg; p.o.) was evaluated for its analgesic activity by employing acetic acid-induced writhing test, hot plate test and tail immersion tests i.e. in hot and cold water. AEAHA (400- 700 mg/kg; p.o.) showed significant (P<0.01) reduction in the number of writhing induced by acetic acid,increased reaction time in hot plate test and elevated pain threshold in hot and cold water tests. AEAHA exhibited the dose-dependent analgesic effects


Author(s):  
Jitendra Kumar Chaudhary ◽  
Alok Pal Jain ◽  
O. P. Tiwari

The goal of the study was to develop, synthesise, and characterise a novel 1,3,5-trisubstituted-2-pyrazolines derivative, as well as to assess its analgesic potential. The reaction of chalcone derivatives with 4-hydrazinylbenzene sulfonamide hydrochloride and phenyl hydrazine hydrochloride yielded 1,3,5-tri-substituted-2-pyrazolines derivatives. The IR, 1HNMR, and mass spectrum analyses were used to characterise a total of sixteen substances. Analgesic activity of the proposed substances has been tested. The analgesic effect of the produced compounds was tested using two methods: the hot plate test technique and acetic acid induced writhing in mice. To compare the effectiveness, pentazocine and acetyl acetic acid were utilised as reference drugs. The hot plate test technique and acetic acid induced writhing in mice were used to assess the analgesic effect of the 16 produced chemical series A1-A8, and B1-B8. The evaluation's outcomes were viewed using Pentazocine and acetyl acetic acid as the standard drugs. In a 90-minute hot plate test, compounds A2 (10.30 s), A4 (9.45 s), A7 (11.65 s), and A8 (11.26 s) showed a delay in paw withdrawal latency time. Compounds B2 (9.10 s) and B7 (10.42 s) prolong the paw withdrawal latency time after 90 minutes in series B1-B8, reduce the pain feeling, and inhibit pain induced by heat methods. Compounds A2, A5, A6, A7, and A8 from Series A1-A8 showed 83.00, 76.01, 80.34, 86.99, 88.15 percent inhibition, substantially (p0.05 and p0.001, respectively), and decreased the number of wriths caused by 0.6 percent acetic acid at a dosage of 10 mg/kg. Acetylsalicylic acid (10 mg/kg) appears to be more successful in lowering the number of wriths, with a 99.0% reduction in the number of wriths (p0.001). B1, B3, and B4 have the least amount of active activity. These all finding suggest that these synthesized compounds have the potential as analgesic agent.


Folia Medica ◽  
2012 ◽  
Vol 54 (4) ◽  
pp. 69-77 ◽  
Author(s):  
Ilia D. Kostadinov ◽  
Delian P. Delev ◽  
Ivanka I. Kostadinova

Abstract INTRODUCTION: Tricyclic antidepressants are used in the treatment of various pain syndromes. The antidepressant clomipramine inhibits predominantly the reuptake of serotonin in the central nervous system. The mechanism of its analgesic effect is not fully understood. The AIM of the present study was to find experimentally any dose-effect dependence in the analgesic effect of clomipramine and the involvement of the 5-НТ2 and 5-НТ3 receptors in the mechanism of this effect. Material and methods: Fifty male Wistar rats were used in the study allocated to five groups (10 animals each): a saline treated control group, one positive control group treated with metamizole and three experimental groups treated with intraperitoneally administered clomipramine in doses of 5, 10 and 20 mg/kg bw, respectively. To study the role of 5-НТ2 and 5-НТ3 receptors in this effect we used another five groups (10 animals each): control, positive control and three experimental groups treated with clomipramine only, clomipramine and granisetrone and clomipramine and cyproheptadine, respectively. Three nociceptive tests were used: the hot plate test, analgesimeter and the acetic acid-induced writhing test. To gauge the antinociceptive action we used the increased latency in the hot plate test expressed as maximum possible effect % (%MPE), the increase in paw pressure to withdraw the hind paw in analgesimeter and decrease in the number of spinal cord writhes in the acetic acid test. RESULTS: Clomipramine in a dose of 20 mg/kg bw significantly increased the %MPE in hot plate test and the pressure to withdraw the hind paw in the analgesimeter when compared with the control. In the acetic acid test clomipramine decreased non-significantly the number of writhes compared with the controls. Granisetrone reduced non-significantly the antinociceptive effect of clomipramine in all tests. Cyproheptadine potentiated the analgesic effect of clomipramine in acetic acid test and decreased it significantly in the hot plate test. In analgesimeter cyproheptadine decreased significantly the paw pressure to withdraw the tested hind paw at 1 hour and non-significantly at 2 hours. CONCLUSION: Clomipramine in the dose of 20 mg/kg bw has a pronounced antinociceptive affect towards thermal and mechanical pain stimulation. The 5-HT2 and 5-HT3 receptor subtypes are very likely involved in the mechanism of this effect.


Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4584 ◽  
Author(s):  
Thais Biondino Sardella Giorno ◽  
Carlos Henrique Corrêa dos Santos ◽  
Mario Geraldo de Carvalho ◽  
Virgínia Cláudia da Silva ◽  
Paulo Teixeira de Sousa ◽  
...  

Infusions of roots of Siolmatra brasiliensis (Cogn.) Baill, (“taiuiá”, “cipó-tauá”) are used for toothache pain and ulcers. We aimed to study the antinociceptive effects and identify the possible mechanism of action of this plant and its isolated substances (cayaponoside A1, cayaponoside B4, cayaponoside D, and siolmatroside I). Hydroethanol extract (HE), ethyl acetate fraction (EtOAc), and isolated saponins were evaluated in chemical and thermal models of pain in mice. Animals were orally pretreated and evaluated in the capsaicin- or glutamate-induced licking and in the hot plate tests. The antinociceptive mechanism of action was evaluated using the hot plate test with the following pretreatments: Atropine (cholinergic antagonist), naloxone (opioid antagonist), or L-NAME (nitric oxide synthase inhibitor). All extracts and isolated saponins increased the area under the curve in the hot plate test. Tested substances induced a higher effect than the morphine-treated group. Our data suggest that stems of S. brasiliensis and their isolated substances present antinociceptive effects. Cholinergic and opioidergic pathways seem to be involved in their mechanism of action. Taken together our data corroborate the traditional use of the plant and expands the information regarding its use.


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