RESUMO
Objective To evaluate the changes in the expression of c-fos protein in the spinal cord in a rat model of oxycodone dependence or withdrawal response.Methods Thirty SPF adult male Sprague-Dawley rats,aged 6-8 weeks,weighing 180-220 g,were divided into 3 groups (n=10 each) using a random number table method:normal saline group (group NS),oxycodone dependence group (group OD),and oxycodone withdrawal group (group OW).In OD and OW groups,oxycodone was injected subcutaneously in back,5 days in total,with the dose of 2,3,4,5 and 6 mg/kg in turn,3 times a day (8:00/15:00/22:00).The equal volume of normal saline was given instead in group NS.The mechanical paw withdrawal threshold was measured at 3 days before administration and 30 min after the last administration every day.The oxycodone withdrawal was induced by intraperitoneal injection of naloxone 4 mg/kg at 8 h after the last administration of oxycodone on 5th day in group OW.The withdrawal response scores and range of weight changes were recorded within 15 min after giving naloxone or normal saline in NS and OW groups.Spinal cord tissues were collected at 1 h after the last administration on 5th day in group OD and at 1 h after giving normal saline or naloxone on 5th day in NS and OW groups for determination of the expression of c-fos protein by Western blot.Results Compared with group NS,the mechanical paw withdrawal threshold was significantly increased on 1 and 2 days after administration,and the expression of c-fos protein in the spinal cord was up-regulated in OD and OW groups,and withdrawal response scores were significantly increased,and the range of weight change was increased in group OW (P＜0.05).The expression of c-fos protein was significantly down-regulated in group OW as compared with group OD (P＜0.05).Conclusion Oxycodone dependence or withdrawal response may be related to the expression of c-fos protein in the spinal cord of rats,and the expression is up-regulated during oxycodone dependence,while down-regulated during oxycodone withdrawal.
RESUMO
Objective To compare the effects of different administration routes and dosages of tropisetron on cisplatin-induced kaolin intake in rats.Methods Ninety-six healthy adult male Wistar SPF rats were randomly divided into 8 groups(n =12 each):intrathecal (IT) control group (group TC) and 3 tropisetron groups receiving IT tropisetron 10,20 and 30 μg,the volume of each group was 30 μl (group T10,T20,T30),intravenous(Ⅳ) control group (group IC) and 3 tropisetron groups receiving Ⅳ tropisetron 0.3,0.5 and 0.7 mg/kg respectively (group I0.3,I0.5,I0.7).In group TC and IC,normal saline 30 μl and 0.5 ml were injected IT and Ⅳ,respectively.All rats received cisplatin 3mg/kg by intraperitoneal injection at the time point of thirty minutes after administration,each rat weight,the daily food and kaolin intakes were detected at the time point of 48 hours after cisplatin administration.Results Compared with group Tc,each rat weight loss,the kaolin intakes were significantly decreased (P ＜ 0.05),and food intake dose was significantly increased in group T20 (P ＜ 0.05).Compared with group IC,each rat weight loss,the kaolin intakes were significantly decreased (P ＜ 0.05),and food intake dose was significantly increased in group I0.5 and I0.7 (P ＜0.05).There was no significant difference between group I0.5,I0.7 and group T20.Conclusions The kaolin intakes and the rat weight loss can be decreased by IT tropisetron,and the food take dose was increased meanwhile,and IT tropisetron 20 μg has equivalent efficacy to IV tropisetron 0.5 or 0.7 mg/kg.IT could be the new administration route of tropisetron.
RESUMO
Objective To investigate the delayed alteration of hippocampus proteome after an-esthesia with isoflurane in aduh and aged rats. Methods Ten 8-month-old SD rats were randomly divided into group Caduh and group Iadult (5 in each group) , and another ten 22-month-old SD rats were randomly divided into group Caged and group Iaged (5 in each group). The rats in group Iadult and group Iaged received 2 h anesthesia with 1.2 % isoflurane. The rats in group Cadult and group Caged inhaled 40% oxygen for contrast. The hippocampal proteome of each rat was measured by 2-dimensional gel electrophoresis and mass spectrometry. Results The vital signs of the rats in group Iadult and group Iaged were stable. There were 878±34 protein spots in group Cadult, 864±49 protein spots in group Iadult, 834±47 in group Caged, and 819±24 in group Iaged. There were 12 (4/8)different protein spots between group Iadult and group Cadult. There were 11 (3/8) different protein spots between group Iaged and group Caged. All of the protein spots were identified by MALDI-TOF-MS. Most of the different proteins were related to metabolism, anti-oxidation, and signal conditioning of synapse. Conclusion Isoflurane may cause the alteration of hippocampal pro-teome in rats, which is age-related.