Effect of ibudilast-microinjected into nucleus accumbens on appendix pain threshold in morphine-addicted rats / 实用肿瘤学杂志

Objective The aim of this study was to investigate the effect of microinjection ibudilast on the appendix pain threshold in nucleus accumbens(NAC)of morphine-addicted rats. Methods Normal rats and morphine-addicted rats were injec-ted with ibudilast(5 μg/2 μL)or saline(2 μL)into NAC through glass microelectrode. The tail-flick period(TFL)was used as an in-dicator to observe the thermal pain threshold before and after ibuilast injection. Results After injected ibudilast 5 μg into the NAC of normal rats and morphine-added rats,the TFL was prolonged compared with that before injection,and the TFL prolongation of mor-phine-addicted rats was more significant than that of normal rats. There was no significant change in TFL after 2 μL of saline was in-jected into the NAC of normal rats and morphine-addicted rats. Conclusion Microinjection of ibudilast into NAC of normal rats and morphine-added rats can cause analgesic effect,and the analgesic effect of morphine-addicted rats is more significant.

Analgesic activity of allopurinol and febuxostat in experimental animals

Background: Currently, two classes of analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs) and opioid analgesics are used to manage pain in different clinical situations. Chronic uses of these drugs have various adverse effects like gastric ulceration/bleeding, analgesic nephropathy and respiratory depression, physical dependence, addiction, respectively. Xanthine oxidase inhibitors, used for chronic gout, might have a role in alleviation of pain, as per literature survey. Hence, the present study was carried out to evaluate the potential analgesic activity of allopurinol and febuxostat in different experimental models.Methods: The analgesic activity of allopurinol and febuxostat was assessed by employing two different experimental pain models-tail flick latency model in rats for central analgesia and acetic acid induced writhing model in mice for peripheral analgesia and was compared with tramadol and aspirin.Results: Allopurinol and febuxostat produced significant central and peripheral analgesic effects as is evident from increase in reaction time in tail flick test and inhibition in number of writhes in acetic acid induced writhing test.Conclusions: The results of the present study demonstrate marked analgesic effect of allopurinol and febuxostat.

Tiopental altera a resposta nociceptiva de ratos jovens em longo prazo / Thiopental alters long term nociceptive response of young rats

The objective of this study was to evaluate the long term nociceptive response determined by use of two general anesthetics, one intravenous and the other inhalatory, in young animals. In the first experiment, the animals of 21 days of age were divided into control (saline) and thiopental (35 mg/kg, i.p.) groups. In the second experiment, rats of the same age were divided in two groups ­ halothane (2%) and control. In experiment 1, there was difference between groups ­ reduction of tail-flick latency in the group thiopental (P< 0.05). In experiment 2, there were no differences between groups or interaction between time versus group (F(1,19)=0.11 for groups, P>0.05; F(1,19)=0.032 for the interaction, P>0.05). The results obtained in this study showed that halothane did not alter the nociceptive response in young animals. However, the thiopental induced hyperalgesic response in rats. (AU)

O objetivo desse estudo foi avaliar a resposta nociceptiva a longo prazo relacionada ao uso de dois anestésicos gerais ­ um intravenoso e outro inalatório, em animais jovens. No primeiro experimento, os animais de 21 dias de idade foram divididos nos grupos controle (solução salina) e tiopental sódico (35 mg/kg, i.p.). No segundo experimento, animais de mesma idade foram divididos em dois grupos ­ halotano (2%) e controle. No Experimento 1, houve redução da latência de retirada da cauda no grupo tiopental (P<0,05). No Experimento 2, não houve diferença entre os grupos ou interação entre grupo x tempo (F(1,19)=0,11 para grupos, P>0,05; F(1,19)=0,032 para a interação, P>0,05). Os resultados obtidos nesse estudo demonstraram que o halotano não altera a resposta nociceptiva em animais jovens. Entretanto, o tiopental induziu resposta hiperalgésica nestes ratos.(AU)

Attenuating effect of seeds of Adenanthera pavonina aqueous extract in neuropathic pain in streptozotocin-induced diabetic rats: an evidence of neuroprotective effects

The aim of present study was to investigate the attenuating effects of Adenanthera pavonina L., Leguminosae-Mimosaceae seeds aqueous extract (APSAE), in streptozotocin (STZ)-induced diabetic neuropathy in rats. APSAE (50, 100 and 200 mg/kg per day) was given to diabetic rats for twelve weeks. Cold and hot water tail immersion tests, photoactometer and Rota-rod tests were performed to assess degree of colder, thermal, spontaneous motor activity and motor co-ordination changes respectively at different time intervals i.e., week 0, 4, 8 and 12. Tissue superoxide anion and total calcium levels were determined after twelve weeks to assess biochemical alterations. Histopathological evaluations of sciatic nerve were also performed to assess nerve damage. APSAE treatment increased tail flick latency significantly in diabetic rats. APSAE also reduced superoxide anion and total calcium levels. These results suggested that APSAE has attenuated development of diabetic neuropathy in streptozotocin-induced diabetic rats when compared with pregabalin (10 mg/kg, p.o.) and could be beneficial in preventing the progression of diabetic nephropathy.

Evaluation of antiinflammatory and analgesic activities of alcoholic extract of kaempferia galanga in rats.

Alcoholic extract of Kaempferia galanga was tested for analgesic and antiinflammatory activities in animal models. Three doses, 300 mg/kg, 600 mg/kg and 1200 mg/kg of the plant extract prepared as a suspension in 2 ml of 2% gum acacia were used. Acute and sub acute inflammatory activities were studied in rats by carrageenan induced paw edema and cotton pellet induced granuloma models respectively. In both models, the standard drug used was aspirin 100 mg/kg. Two doses 600 mg/kg and 1200 mg/kg of plant extract exhibited significant (P<0.001) antiinflammatory activity in carrageenan model and cotton pellet granuloma model in comparison to control. Analgesic activity was studied in rats using hot plate and tail-flick models. Codeine 5 mg/kg and vehicle served as standard and control respectively. The two doses of plant extract exhibited significant analgesic activity in tail flick model (P<0.001) and hot plate model (P<0.001) in comparison to control. In conclusion K. galanga possesses antiinflammatory and analgesic activities.