Objective To investigate the potential role of estrogen in the formation of granulation tissue hyperplasia-induced tracheal stenosis in rats.Methods Twenty-four female SD rats were ran-domly divided into three groups(n=8)using a random number table method:sham group(n=8),ovariectomized(OVX)group(bilateral ovariectomy,n=8),and ovariectomized+estrogen(OVX+E2)group(bilateral ovariectomy followed by exogenous estrogen intervention,n=8).Four weeks af-ter establishment of the Sham and OVX rat models,a granulation tissue hyperplasia-induced tracheal stenosis model was constructed in all rats using the oral nylon brush scraping method.On the first day of modeling,rats in the OVX+E2 group were administered 17β-E2 at a dose of 300 μg/kg via intrap-eritonealinjection daily,while rats in the other two groups were given the same volume of normal saline.After 7 consecutive days of administration,tracheal specimens were obtained.Hematoxylin and eosin(HE)staining was used to observe the pathological changes of tracheal granulation tissue hyperplasia in each group and calculate the tracheal stenosis rate.Masson staining was employed to analyze the collagen fibers in the tracheal granulation tissue and calculate the relative collagen deposition area.Immunohistochemical(IHC)staining was used to detect the protein expression levels of transforming growth factor-beta 1(TGF-β 1),vascular endothelial growth factor(VEGF),alpha-smooth muscle actin(α-SMA),and collagen type Ⅰ(COL-Ⅰ)in the tracheal granulation tissue,and the average optical density(AOD)was calculated.Results HE staining revealed granulation tissue hyperplasi-a and tracheal lumen stenosis in the tracheal walls of all three groups.The stenosis rate was the highest in the OVX+E2 group,followed by the sham group,and the lowest in the OVX group,with statistically significant differences(P＜0.05).Masson staining showed that the collagen fibers in the sham group were thicker and denser with more collagen deposition compared to the OVX group.In contrast,the OVX+E2 group had even thicker and denser collagen fibers with more collagen dep-osition than the sham group.IHC staining demonstrated that the protein expression levels of COL-Ⅰ,TGF-β1,VEGF,and α-SMA in the tracheal granulation tissue were the lowest in the OVX group,fol-lowed by the sham group,and the highest in the OVX+E2 group.Conclusion Estrogen can acceler-ate tracheal granulation tissue hyperplasia by upregulating the protein expression levels of COL-Ⅰ,TGF-β1,and VEGF,as well as promoting fibroblast activation,leading to aggravated tracheal stenosis.

Objective:To explore the expression changes of nerve growth factor (NGF)/tropomyosin receptor kinase A (TrkA) signaling pathway of dorsal root ganglia (DRG) in incisional rat remifentanil-induced hyperalgesia and its effect on the expression of membrane delta opioid receptor (DOR).Methods:A total of 48 SPF male SD rats were randomly divided into 6 groups based on body weight matching, with 8 in each group, which were control group (infusion of 0.9% NaCl solution via the tail vein), incision pain group (incision pain model established using the Brennan method), remifentanil group (infusion of remifentanil via the tail vein), incision pain+ remifentanil model group (incision pain model established using the Brennan method, followed by infusion of remifentanil via the tail vein), NGF group and TrkA inhibitor group(established incision pain+ remifentanil model after intrathecal injection of NGF (0.06 μg/g) or K252a (0.3 μg/g, TrkA inhibitor)). Mechanical paw withdrawal threshold (PWT) was used to assess pain sensitivity in rats. Western blot was employed to measure the expression of NGF, TrkA, and the total DOR(tDOR) and the membrane DOR(mDOR) in DRG tissues. Immunoelectron microscopy was used to detect subcellular DOR expression in DRG. Data were processed using SPSS 24.0 software. Multiple comparisons among groups were conducted by repeated measures ANOVA or one-way ANOVA, and post-hoc comparisons were performed using the Bonferroni test.Results:(1) The results of pain behavior showed that there was a significant interaction effect between time and group in the comparison of PWT among the six groups of rats before and after intervention ( F=345.817, P<0.001). At each time point after intervention, the PWTs of the incision pain+ remifentanil group were lower than those of the incision pain group and remifentanil group, the PWTs of the NGF group were lower than those of the incision pain+ remifentanil group, and the PWTs of the TrkA inhibitor group were higher than those of the incision pain+ remifentanil group and NGF group (all P<0.05). (2)The Western blot results showed that there were statistically significant differences in the relative levels of NGF, TrkA, and mDOR in the DRG tissues of the six groups of rats ( F=156.2, 163.8, 421.2, all P<0.001). The levels of NGF, TrkA, and mDOR proteins in the incision pain+ remifentanil group (1.45±0.07, 1.46±0.04, 3.01±0.20) were higher than those in the incision pain group (1.25±0.05, 1.24±0.04, 1.84±0.05) and remifentanil group (1.24±0.04, 1.26±0.03, 1.84±0.04) (all P<0.05). The levels of NGF, TrkA, and mDOR in the NGF group (1.57±0.03, 1.58±0.07, 3.74±0.25) were higher than those in the incision pain+ remifentanil group (all P<0.05). The relative expression levels of TrkA, and mDOR in the TrkA inhibitor group (1.25±0.04, 1.68±0.07) were lower than those in the incision pain+ remifentanil group and the NGF group (all P<0.05). (3)The results of immunoelectron microscopy showed that there were statistically significant differences in the localization of DOR in the cell membrane, subcellular sites of synthesis pathways, and subcellular localization of degradation pathways among the six groups of rat DRG tissues ( F=140.3, 60.63, 60.28, all P<0.01). The DOR of the synthesis pathway of incision pain+ remifentanil group was higher than that of the incision pain group and remifentanil group, while the DOR of the synthesis pathway of NGF was higher than that of the incision pain+ remifentanil group.The DOR of the synthesis pathway of TrkA inhibitor group was lower than that of the incision pain+ remifentanil group and NGF group (both P<0.05). The DOR of the degradation pathway in the incision pain+ remifentanil group was lower than that in the incision pain group and remifentanil group, the DOR of the degradation pathway in the NGF group was lower than that in the incision pain+ remifentanil group, and the DOR of the degradation pathway in the TrkA inhibitor group was higher than that in the incision pain+ remifentanil group and NGF group (both P<0.05). Conclusion:The NGF/TrkA signaling pathway is involved in rat incisional pain-remifentanil hyperalgesia by upregulating the delta opioid receptor of the dorsal root ganglia.

Objective:To explore the expression changes of nerve growth factor (NGF)/tropomyosin receptor kinase A (TrkA) signaling pathway of dorsal root ganglia (DRG) in incisional rat remifentanil-induced hyperalgesia and its effect on the expression of membrane delta opioid receptor (DOR).Methods:A total of 48 SPF male SD rats were randomly divided into 6 groups based on body weight matching, with 8 in each group, which were control group (infusion of 0.9% NaCl solution via the tail vein), incision pain group (incision pain model established using the Brennan method), remifentanil group (infusion of remifentanil via the tail vein), incision pain+ remifentanil model group (incision pain model established using the Brennan method, followed by infusion of remifentanil via the tail vein), NGF group and TrkA inhibitor group(established incision pain+ remifentanil model after intrathecal injection of NGF (0.06 μg/g) or K252a (0.3 μg/g, TrkA inhibitor)). Mechanical paw withdrawal threshold (PWT) was used to assess pain sensitivity in rats. Western blot was employed to measure the expression of NGF, TrkA, and the total DOR(tDOR) and the membrane DOR(mDOR) in DRG tissues. Immunoelectron microscopy was used to detect subcellular DOR expression in DRG. Data were processed using SPSS 24.0 software. Multiple comparisons among groups were conducted by repeated measures ANOVA or one-way ANOVA, and post-hoc comparisons were performed using the Bonferroni test.Results:(1) The results of pain behavior showed that there was a significant interaction effect between time and group in the comparison of PWT among the six groups of rats before and after intervention ( F=345.817, P<0.001). At each time point after intervention, the PWTs of the incision pain+ remifentanil group were lower than those of the incision pain group and remifentanil group, the PWTs of the NGF group were lower than those of the incision pain+ remifentanil group, and the PWTs of the TrkA inhibitor group were higher than those of the incision pain+ remifentanil group and NGF group (all P<0.05). (2)The Western blot results showed that there were statistically significant differences in the relative levels of NGF, TrkA, and mDOR in the DRG tissues of the six groups of rats ( F=156.2, 163.8, 421.2, all P<0.001). The levels of NGF, TrkA, and mDOR proteins in the incision pain+ remifentanil group (1.45±0.07, 1.46±0.04, 3.01±0.20) were higher than those in the incision pain group (1.25±0.05, 1.24±0.04, 1.84±0.05) and remifentanil group (1.24±0.04, 1.26±0.03, 1.84±0.04) (all P<0.05). The levels of NGF, TrkA, and mDOR in the NGF group (1.57±0.03, 1.58±0.07, 3.74±0.25) were higher than those in the incision pain+ remifentanil group (all P<0.05). The relative expression levels of TrkA, and mDOR in the TrkA inhibitor group (1.25±0.04, 1.68±0.07) were lower than those in the incision pain+ remifentanil group and the NGF group (all P<0.05). (3)The results of immunoelectron microscopy showed that there were statistically significant differences in the localization of DOR in the cell membrane, subcellular sites of synthesis pathways, and subcellular localization of degradation pathways among the six groups of rat DRG tissues ( F=140.3, 60.63, 60.28, all P<0.01). The DOR of the synthesis pathway of incision pain+ remifentanil group was higher than that of the incision pain group and remifentanil group, while the DOR of the synthesis pathway of NGF was higher than that of the incision pain+ remifentanil group.The DOR of the synthesis pathway of TrkA inhibitor group was lower than that of the incision pain+ remifentanil group and NGF group (both P<0.05). The DOR of the degradation pathway in the incision pain+ remifentanil group was lower than that in the incision pain group and remifentanil group, the DOR of the degradation pathway in the NGF group was lower than that in the incision pain+ remifentanil group, and the DOR of the degradation pathway in the TrkA inhibitor group was higher than that in the incision pain+ remifentanil group and NGF group (both P<0.05). Conclusion:The NGF/TrkA signaling pathway is involved in rat incisional pain-remifentanil hyperalgesia by upregulating the delta opioid receptor of the dorsal root ganglia.

Objective:To evaluate the role of sphingosine-1-phospho-1 receptor 1 (S1PR1) in remifentanil-induced hyperalgesia in rats with incisional pain and the relationship with KCNQ2/3 potassium channels in the dorsal root ganglia (DRG).Methods:Forty-eight male Sprague-Dawley rats with successful caudal vein catheterization, aged 2-3 months, weighing 260-280 g, were divided into 6 groups ( n=8 each) using a random number table method: control group (group C), S1PR1 inhibitor group (FTY720) group (group F), remifentanil group (group R), remifentanil + S1PR1 inhibitor (FTY720) group (group RF), remifentanil + incision pain group (group RI) and remifentanil + incision pain + S1PR1 inhibitor (FTY720) group (group RIF). In group C, normal saline 0.1 ml· kg -1·min -1 was intravenously infused for 60 min. In group F, FTY720 3 nmol was intrathecally injected at 10 min before normal saline injection, and 0.1 ml · kg -1·min -1 normal saline was infused into the caudal vein for 60 min. Remifentanil 1.0 μg· kg -1·min -1 was infused for 60 min through the caudal vein in group R. In RF group, FTY720 (3 nmol) was intrathecally injected, and 10 min later remifentanil 1.0 μg· kg -1·min -1 was infused via the caudal vein for 60 min. The incisional pain model was established, and remifentanil 1.0 μg· kg -1·min -1 was infused via the caudal vein for 60 min in RI group. In RIF group, FTY720 3 nmol was intrathecally injected at 10 min before remifentanil infusion, then the incisional pain model was developed, and remifentanil 1.0 μg· kg -1·min -1 was infused via the caudal vein at the same time for 60 min. The mechanical paw withdraw threshold (MWT) and thermal paw withdraw latency (TWL) were measured at 24 h before remifentanil or normal saline infusion (T 0) and 2, 6, 24 and 48 h after remifentanil or normal saline infusion (T 1-4). The rats were sacrificed after the last measurement of pain threshold, and the L 4-6 segments of the DRG were taken for determination of the expression of S1PR1, KCNQ2 and KCNQ3 protein and mRNA in the DRG by Western blot and real-time polymerase chain reaction. Results:Compared with group C, the MWT was significantly decreased, and the TWL was shortened at T 1-4, the expression of S1PR1 protein and mRNA in the DRG was up-regulated, the expression of KCNQ2 and KCNQ3 protein and mRNA in the DRG was down-regulated ( P<0.05), and no significant change was found in each parameter in R and RI groups ( P>0.05). Compared with group R, the MWT was significantly decreased, and the TWL was shortened at T 1-4, the expression of S1PR1 protein and mRNA in the DRG was up-regulated, and the expression of KCNQ2 and KCNQ3 protein and mRNA in the DRG was down-regulated in group RI, and the MWT was significantly increased, and the TWL was prolonged at T 1-4, the expression of S1PR1 protein and mRNA in the DRG was down-regulated, and the expression of KCNQ2 and KCNQ3 protein and mRNA in the DRG was up-regulated in group RF ( P<0.05). Compared with group RI, the MWT was significantly increased, and the TWL was prolonged at T 1-4, the expression of S1PR1 protein and mRNA in the DRG was down-regulated, and the expression of KCNQ2 and KCNQ3 protein and mRNA in the DRG was up-regulated in group RIF ( P<0.05). Conclusions:S1PR1 is involved in the process of remifentanil-induced hyperalgesia in rats with incisional pain, which is related to the inhibition of KCNQ2/3 potassium channel expression in the DRG.

Objective:To investigate the reproductive toxicity of cadmium sulfide nanoparticles (Nano-CdS) with different particle sizes on male mice.Methods:In January 2019, 30 SPF grade male mice were randomly divided into a control group, an experimental group[CdS Ⅰ group (particle size approximately 5 nm), and a CdS Ⅱ group (particle size approximately 50 nm) ], with 10 mice in each group. The experimental group was orally gavaged with 100 mg/kg, once a day, while the control group was gavaged with an equal volume of physiological saline for 45 consecutive days. After 45 days, levels of cadmium accumulation in testis were determined directly by AAS, deformity and testicular histopathological changes were also observed. Serum testosterone levels were measured by enzyme-linked immunosorbentassay (ELISA), expression levels of P450scc, 17β-HSD and P450c17 mRNA were determined by real-time PCR. P450c17 protein was determinated by Western Blot.Results:The histopathological results showed that the testes of the experimental group mice showed varying degrees of damage; Ultrastructural observation showed that the ultrastructure of mouse testicular cells in each experimental group showed varying degrees of mitochondrial expansion and disappearance of cristae, as well as irregular nuclear membranes. The degree of damage in CdS Ⅰ group was milder than that in CdS Ⅱ group. Compared with the control group, the cadmium content in the testes of the CdS Ⅰ and CdS Ⅱ groups significantly increased ( P=0.001, 0.001), and the CdS Ⅱ group was higher than the CdS Ⅰ group ( P=0.001). Compared with the control group, the levels of testosterone in the CdS Ⅰ and CdS Ⅱ groups decreased with statistical significance ( P=0.001, 0.001). Real time fluorescence quantitative PCR results showed that compared with the control group, the experimental group's P450scc, 17β-HSD. The expression levels of 17β-HSD and P450c17 mRNA were significantly reduced, with statistically significant differences ( P=0.001, 0.001, 0.001), and CdS Ⅱ group 17β-HSD. The expression levels of 17β-HSD and P450c17 mRNA were significantly lower than those of CdS Ⅰ group ( P=0.001, 0.036). The Western Blot assay results showed that the expression levels of P450c17 protein in the testes of CdS Ⅰ and CdS Ⅱ groups of mice were significantly reduced, with statistical significance ( P=0.001, 0.001) ; And the CdS Ⅱ group was significantly lower than the CdS Ⅰ group ( P=0.001). According to Spearman correlation analysis, testosterone levels are correlated with P450scc, P450c17, 17β-HSD mRNA. There is a highly positive correlation between 17β-HSD mRNA levels, with statistically significant differences ( rs=0.88, 0.80, 0.70, P=0.001, 0.001, 0.004) . Conclusion:Nano cadmium sulfide may induce reproductive toxicity by reducing the expression levels of key enzyme genes and enzyme protein activity in testosterone and its synthesis in mice, and the CdS Ⅱ group has a stronger toxic effect.

Objective:To investigate the reproductive toxicity of cadmium sulfide nanoparticles (Nano-CdS) with different particle sizes on male mice.Methods:In January 2019, 30 SPF grade male mice were randomly divided into a control group, an experimental group[CdS Ⅰ group (particle size approximately 5 nm), and a CdS Ⅱ group (particle size approximately 50 nm) ], with 10 mice in each group. The experimental group was orally gavaged with 100 mg/kg, once a day, while the control group was gavaged with an equal volume of physiological saline for 45 consecutive days. After 45 days, levels of cadmium accumulation in testis were determined directly by AAS, deformity and testicular histopathological changes were also observed. Serum testosterone levels were measured by enzyme-linked immunosorbentassay (ELISA), expression levels of P450scc, 17β-HSD and P450c17 mRNA were determined by real-time PCR. P450c17 protein was determinated by Western Blot.Results:The histopathological results showed that the testes of the experimental group mice showed varying degrees of damage; Ultrastructural observation showed that the ultrastructure of mouse testicular cells in each experimental group showed varying degrees of mitochondrial expansion and disappearance of cristae, as well as irregular nuclear membranes. The degree of damage in CdS Ⅰ group was milder than that in CdS Ⅱ group. Compared with the control group, the cadmium content in the testes of the CdS Ⅰ and CdS Ⅱ groups significantly increased ( P=0.001, 0.001), and the CdS Ⅱ group was higher than the CdS Ⅰ group ( P=0.001). Compared with the control group, the levels of testosterone in the CdS Ⅰ and CdS Ⅱ groups decreased with statistical significance ( P=0.001, 0.001). Real time fluorescence quantitative PCR results showed that compared with the control group, the experimental group's P450scc, 17β-HSD. The expression levels of 17β-HSD and P450c17 mRNA were significantly reduced, with statistically significant differences ( P=0.001, 0.001, 0.001), and CdS Ⅱ group 17β-HSD. The expression levels of 17β-HSD and P450c17 mRNA were significantly lower than those of CdS Ⅰ group ( P=0.001, 0.036). The Western Blot assay results showed that the expression levels of P450c17 protein in the testes of CdS Ⅰ and CdS Ⅱ groups of mice were significantly reduced, with statistical significance ( P=0.001, 0.001) ; And the CdS Ⅱ group was significantly lower than the CdS Ⅰ group ( P=0.001). According to Spearman correlation analysis, testosterone levels are correlated with P450scc, P450c17, 17β-HSD mRNA. There is a highly positive correlation between 17β-HSD mRNA levels, with statistically significant differences ( rs=0.88, 0.80, 0.70, P=0.001, 0.001, 0.004) . Conclusion:Nano cadmium sulfide may induce reproductive toxicity by reducing the expression levels of key enzyme genes and enzyme protein activity in testosterone and its synthesis in mice, and the CdS Ⅱ group has a stronger toxic effect.

Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic steatosis and insulin resistance and there are currently no approved drugs for its treatment. Hyperactivation of mTOR complex 1 (mTORC1) and subsequent impairment of the transcription factor EB (TFEB)-mediated autophagy-lysosomal pathway (ALP) are implicated in the development of NAFLD. Accordingly, agents that augment hepatic TFEB transcriptional activity may have therapeutic potential against NAFLD. The objective of this study was to investigate the effects of nuciferine, a major active component from lotus leaf, on NAFLD and its underlying mechanism of action. Here we show that nuciferine activated ALP and alleviated steatosis, insulin resistance in the livers of NAFLD mice and palmitic acid-challenged hepatocytes in a TFEB-dependent manner. Mechanistic investigation revealed that nuciferine interacts with the Ragulator subunit hepatitis B X-interacting protein and impairs the interaction of the Ragulator complex with Rag GTPases, thereby suppressing lysosomal localization and activity of mTORC1, which activates TFEB-mediated ALP and further ameliorates hepatic steatosis and insulin resistance. Our present results indicate that nuciferine may be a potential agent for treating NAFLD and that regulation of the mTORC1-TFEB-ALP axis could represent a novel pharmacological strategy to combat NAFLD.

Objective: To explore the effect of distance education in the teaching mode of medical clinical skills, and to provide theoretical and practical basis for finding a better teaching mode to promote the combination of theory and practice. Methods: A total of 172 trainees of clinical skill training in the training center were divided into the control group and the observation group (the observation group was divided into pre-class long-distance group, in-class long-distance group, after-class long-distance group). There were 43 trainees in each group. The control group adopted traditional teaching methods in clinical basic skills courses, and the observation group adopted mixed teaching mode under long-distance education. The satisfaction of teachers and students under the two teaching modes were investigated, and the performance of each group of students in skills, human-computer dialogue, and team first aid comprehensive test were compared. Results: There were significant differences in teacher satisfaction between the control group and the pre-class and in-class distance groups (χ² = 15.315, P = 0.000). There were significant differences in student satisfaction between the control group and the pre-class and in-class distance groups in terms of interactive participation, liveliness, interesting training skills and teaching level (χ²=4.497-17.153, P = 0.000-0.034). The results of each group reached the expected teaching goals. There were significant differences between the skill test score control group and the pre-class and in-class remote groups (t=25.357, 14.712, all P =0.000). There were significant differences between the human-machine dialogue test control group and the three observation groups (t=14.561, 19.420, 3.821, all P =0.000). There were significant differences between the team emergency comprehensive test control group and the three observation groups (t=14.561, 19.420, 3.821, all P=0.000). Conclusions Distance education has flexible in the mixed teaching mode of clinical skills, especially in pre-class and in-class. It can rapidly improve the basic clinical skills, theoretical knowledge and team mobilization ability of students. It is one of the best bridges to communicate their clinical theory and practice.

Objective: To survey the conduction and evaluate the effectiveness of extracorporeal membrane oxygenation (ECMO) therapy in pediatric intensive care unit (PICU) in China mainland. Methods: In a questionnaire-based survey, we retrospectively reviewed the application of ECMO in children's hospital and general hospital in China mainland to summarize and analyze the categories of diseases and prognosis of children treated with ECMO therapy. Results: By December 31, 2017, a total of 23 hospitals using ECMO, including 22 tertiary referral hospitals and 1 secondary hospital, among which 16 were children′s hospitals and 7 were general hospitals. Thirty-seven ECMO equipment was available. A total of 518 patients treated with ECMO, within whom 323 (62.4%) successfully weaned from ECMO and 262 (50.6%) survived to discharge. Among 375 pediatric patients, 233 (62.1%) were successfully weaned from ECMO and 186 (49.6%) survived to discharge. Among 143 newborn patients, 90 (62.9%) successfully weaned from ECMO, 76 (53.1%) survived to discharge. ECMO was applied in veno-arterial (VA) mode to 501 (96.7%) patients, veno-venous (VV) mode to 14 (2.7%) patients, and VV-VA conversion mode to 3 (0.6%) patients. Sixty-nine patients required extracorporeal cardiopulmonary resuscitation (ECPR), including 20 newborn patients (29.0%) and 38 pediatric patients (71.0%), who were all with cardiovascular disease. Neonatal respiratory distress syndrome (26/61), persistent pulmonary hypertension of the newborn (PPHN) (12/61), and meconium aspiration syndrome (MAS) (11/61) are the most common pulmonary diseases in newborn patients; among whom, infants with PPHN had highest survival rate (10/12), followed by MAS (9/11). Among newborn patients with cardiovascular diseases, those who admitted were after surgery for congenital cardiac disease were the most common (54/82), while those with septic shock had the highest survival rate (2/3). In pediatric pulmonary diseases, acute respiratory distress syndrome was the most common (42/93), while plastic bronchitis was with the highest survival rate (4/4), followed by viral pneumonia (13/16). Among pediatric cardiovascular diseases, congenital cardiac defect was the most common (124/282), while fulminant myocarditis had the highest survival rate (54/77). Conclusion The application of ECMO as a rescue therapy for children with severe cardiopulmonary failure has dramatically developed in China mainland.

Objective To investigate the changing characteristics and rules of the different period of articular cartilage in rats after dorsal rhizotomy, and to verify the partial sensory disturbance can cause articular cartilage injury. Methods Thirty-three ten-month-old SPF male Wistar rats were randomly divided into experimental group ( n=18 ) and control group ( n=15) .The rats in the experimental group were sectioned the L3、L4 dorsal roots in the right.The rats in the control group were only incised the skin and paravertebral muscles.To observe the behavior changes in rats.At 2, 6 and 10 weeks, the specimens of the right hind lower end of femur were drawn out to make paraffin sections, then HE staining and Safranin O/Fast Green staining.The changes and characteristics of the morphology of the articular cartilage was observed.Results With the prolonging of period, the right hind limb of the experimental rats through the change process of transient paralysis, coordination of movement disorders and active movement.In the experimental group, the patellar surface of right hind femur gradually became shallow and wide.The articular cartilage underwent rough, cells disorganizated, cells decreased, and duplicated drifted and interrupted tide line. The ratios of ACC/TAC of the experimental group were gradually high(t=5.25~8.13,P <0.05).Conclusion Dorsal rhizotomy can cause injury and degenerative changes in articular cartilage.