Dual-energy computed tomography for predicting cervical lymph node metastasis in laryngeal squamous cell carcinoma.

Rationale and objectives: We constructed a dual-energy computed tomography (DECT)-based model to assess cervical lymph node metastasis (LNM) in patients with laryngeal squamous cell carcinoma (LSCC). Materials and methods: We retrospectively analysed 164 patients with LSCC who underwent preoperative DECT from May 2019 to May 2023. The patients were randomly divided into training (n = 115) and validation (n = 49) cohorts. Quantitative DECT parameters of the primary tumours and their clinical characteristics were collected. A logistic regression model was used to determine independent predictors of LNM, and a nomogram was constructed along with a corresponding online model. Model performance was assessed using the area under the curve (AUC) and the calibration curve, and the clinical value was evaluated using decision curve analysis (DCA). Results: In total, 64/164 (39.0 %) patients with LSCC had cervical LNM. Independent predictors of LNM included normalized iodine concentration in the arterial phase (odds ratio [OR]: 8.332, 95 % confidence interval [CI]: 2.813-24.678, P < 0.001), normalized effective atomic number in the arterial phase (OR: 5.518, 95 % CI: 1.095-27.818, P = 0.002), clinical T3-4 stage (OR: 5.684, 95 % CI: 1.701-18.989, P = 0.005), and poor histological grade (OR: 5.011, 95 % CI: 1.003-25.026, P = 0.049). These predictors were incorporated into the DECT-based nomogram and the corresponding online model, showing good calibration and favourable performance (training AUC: 0.910, validation AUC: 0.918). The DCA indicated a significant clinical benefit of the nomogram for estimating LNM. Conclusions: DECT parameters may be useful independent predictors of LNM in patients with LSCC, and a DECT-based nomogram may be helpful in clinical decision-making.

SPI1 exacerbates iron accumulation and promotes osteoclast formation through inhibiting the expression of Hepcidin.

BACKGROUND: Osteoporosis (OP) can be caused by an overactive osteoclastic function. Anti-osteoporosis considerable therapeutic effects in tissue repair and regeneration because bone resorption is a unique osteoclast function. In this study, we mainly explored the underlying mechanisms of osteoclasts' effects on osteoporosis. METHODS: RAW264.7 cells were used and induced toward osteoclast and iron accumulation by M-CSF and RANKL administration. We investigated Hepcidin and divalent metal transporter 1 (DMT1) on iron accumulation and osteoclast formation in an ovariectomy (OVX)-induced osteoporosis. Osteoporosis was induced in mice by OVX, and treated with Hepcidin (10, 20, 40, 80 mg/kg, respectively) and overexpression of DMT1 by tail vein injection. Hepcidin, SPI1, and DMT1 were detected by immunohistochemical staining, western blot and RT-PCR. The bioinformatics assays, luciferase assays, and Chromatin Immunoprecipitation (ChIP) verified that Hepcidin was a direct SPI1 transcriptional target. Iron accumulation was detected by laser scanning confocal microscopy, Perl's iron staining and iron content assay. The formation of osteoclasts was assessed using tartrate-resistant acid phosphatase (TRAP) staining. RESULTS: We found that RAW264.7 cells differentiated into osteoclasts when exposed to M-CSF and RANKL, which increased the protein levels of osteoclastogenesis-related genes, including c-Fos, MMP9, and Acp5. We also observed higher concentration of iron accumulation when M-CSF and RANKL were administered. However, Hepcidin inhibited the osteoclast differentiation cells and decreased intracellular iron concentration primary osteoclasts derived from RAW264.7. Spi-1 proto-oncogene (SPI1) transcriptionally repressed the expression of Hepcidin, increased DMT1, facilitated the differentiation and iron accumulation of mouse osteoclasts. Overexpression of SPI1 significantly declined luciferase activity of HAMP promoter and increased the enrichment of HAMP promoter. Furthermore, our results showed that Hepcidin inhibited osteoclast differentiation and iron accumulation in mouse osteoclasts and OVX mice. CONCLUSION: Therefore, the study revealed that SPI1 could inhibit Hepcidin expression contribute to iron accumulation and osteoclast formation via DMT1 signaling activation in mouse with OVX.

Geniposide suppressed OX-LDL-induced osteoblast apoptosis by regulating the NRF2/NF-κB signaling pathway.

BACKGROUND: Osteoporosis (OP), due to microarchitectural alterations, is associated with decreased bone mass, declined strength, and increased fracture risk. Increased osteoblast apoptosis contributes to the progression of OP. Natural compounds from herbs provide a rich resource for drug screening. Our previous investigation showed that geniposide (GEN), an effective compound from Eucommia ulmoides, could protect against the pathological development of OP induced by cholesterol accumulation. METHODS: The rat OP models were duplicated. Dual-energy X-ray absorptiometry, hematoxylin and eosin staining, and immunohistochemistry were used to evaluate bone changes. TUNEL/DAPI staining assays were used for cell apoptosis detection. Protein expression was determined by western blotting assays. RESULTS: A high-fat diet promoted OP development in vivo, and OX-LDL stimulated osteoblast apoptosis in vitro. GEN exhibited protective activities against OX-LDL-induced osteoblast apoptosis by increasing the NRF2 pathway and decreasing the NF-κB pathway. PDTC, an NF-κB inhibitor, could further promote the biological functions of GEN. In contrast, ML385, an NRF2 inhibitor, might eliminate GEN's protection. CONCLUSION: GEN suppressed OX-LDL-induced osteoblast apoptosis by regulating the NRF2/NF-κB signaling pathway.

Structural Versus Nonstructural Bone Grafting Via the Posterior Approach in the Treatment of Thoracic and Lumbar Tuberculosis: A Systematic Review and Meta-Analysis.

BACKGROUND: Bone grafting is necessary in spinal tuberculosis surgery. Structural bone grafting is considered the gold standard treatment for spinal tuberculosis bone defects; however, nonstructural bone grafting via the posterior approach has recently gained attention. In this meta-analysis, we evaluated the clinical efficacy of structural versus nonstructural bone grafting via the posterior approach in the treatment of thoracic and lumbar tuberculosis. METHODS: Studies comparing the clinical efficacy of structural and nonstructural bone grafting via the posterior approach in spinal tuberculosis surgery were identified from 8 databases from inception to August 2022. Study selection, data extraction, and evaluation of the risk of bias were performed, and meta-analysis was conducted. RESULTS: Ten studies including 528 patients with spinal tuberculosis were enrolled. Meta-analysis revealed no between-group differences in fusion rate (P = 0.29), complications (P = 0.21), postoperative Cobb angle (P = 0.7), visual analog scale score (P = 0.66), erythrocyte sedimentation rate (P = 0.74), or C-reactive protein level (P = 0.14) at the final follow-up. Nonstructural bone grafting was associated with less intraoperative blood loss (P < 0.00001), shorter operation time (P < 0.0001), shorter fusion time (P < 0.01), and shorter hospital stay (P < 0.00001), while structural bone grafting was associated with lower Cobb angle loss (P = 0.002). CONCLUSIONS: Both techniques can achieve a satisfactory bony fusion rate for spinal tuberculosis. Nonstructural bone grafting has the advantages of less operative trauma, shorter fusion time, and shorter hospital stay, making it an attractive option for short-segment spinal tuberculosis. Nevertheless, structural bone grafting is superior for maintaining corrected kyphotic deformities.

The protective activity of natural flavonoids against osteoarthritis by targeting NF-κB signaling pathway.

Osteoarthritis (OA) is a typical joint disease associated with chronic inflammation. The nuclear factor-kappaB (NF-κB) pathway plays an important role in inflammatory activity and inhibiting NF-κB-mediated inflammation can be a potential strategy for treating OA. Flavonoids are a class of naturally occurring polyphenols with anti-inflammatory properties. Structurally, natural flavonoids can be divided into several sub-groups, including flavonols, flavones, flavanols/catechins, flavanones, anthocyanins, and isoflavones. Increasing evidence demonstrates that natural flavonoids exhibit protective activity against the pathological changes of OA by inhibiting the NF-κB signaling pathway. Potentially, natural flavonoids may suppress NF-κB signaling-mediated inflammatory responses, ECM degradation, and chondrocyte apoptosis. The different biological actions of natural flavonoids against the NF-κB signaling pathway in OA chondrocytes might be associated with the differentially substituted groups on the structures. In this review, the efficacy and action mechanism of natural flavonoids against the development of OA are discussed by targeting the NF-κB signaling pathway. Potentially, flavonoids could become useful inhibitors of the NF-κB signaling pathway for the therapeutic management of OA.

Isolated cryptococcal osteomyelitis of the sacrum in an immunocompetent patient: a case report and literature review.

BACKGROUND: Cryptococcus neoformans, an opportunistic fungal pathogen, seldom causes infection in immunocompetent people. Cryptococcal osteomyelitis is an uncommon condition in which Cryptococcus invades the bone. It usually occurs as part of a disseminated infection and rarely in isolation. The spine has been reported as the most common site of cryptococcal osteomyelitis; however, isolated case of sacrum involvement in immunocompetent patients has never been reported. CASE PRESENTATION: We report the case of a 37-year-old man without underlying disease who presented with progressive low back and sacrococcygeal pain. The patient was initially diagnosed with sacral tumour by a local doctor, and subsequently, after admission, was diagnosed with sacral tuberculosis. He was empirically treated with antitubercular drugs. The patient failed to respond to antitubercular drugs and complained of worsening low back pain. Additionally, he developed persistent radiating pain and numbness in his legs. For further diagnosis, we performed a computed tomography-guided puncture biopsy of the sacrum, which revealed granulomatous inflammation with massive macrophage infiltration and special staining revealed a fungal infection. We performed sacral debridement and drainage and obtained purulent specimens for pathological examination and microbial culture. Microbial identification and drug susceptibility tests revealed a Cryptococcus neoformans infection sensitive to fluconazole. Postoperatively, the persistent radiating pain and numbness in the legs resolved. After 12 consecutive weeks of antifungal therapy, all his symptoms resolved. The patient remained without any signs of recurrence at the 8-month follow-up. CONCLUSION: We reported a rare case of isolated sacrum cryptococcal osteomyelitis in an immunocompetent patient. Furthermore, we identified and reviewed 18 published cases of spine cryptococcal osteomyelitis. Immunocompetent individuals are also at risk for cryptococcal osteomyelitis. Clinical manifestation and imaging are insufficient to diagnose cryptococcal osteomyelitis of the spine, and invasive examinations, such as puncture biopsy and fungal examinations, are needed. Antifungal therapy yields satisfactory results for the treatment of cryptococcal osteomyelitis of the spine, however, if the infective lesion is large, especially when it compresses the spinal cord and nerves, a regimen combining aggressive surgery with antifungal therapy is indispensable.

Geniposide ameliorates glucocorticoid-induced osteoblast apoptosis by activating autophagy.

Long-term exposure to glucocorticoid (GC) contributes to the development of osteoporosis (OP), which is correlated with the risk of fracture. Pathologically, GC-induced bone loss is associated with osteoblast apoptosis. Geniposide (GEN), a natural occurring compound derived from Eucommia ulmoides, has been reported to ameliorate dexamethasone (DEX)-induced OP. Our previous study shows that GEN exhibits protective activity against DEX-induced OP by attenuating endoplasmic reticulum stress and decreasing apoptosis in osteoblasts. However, the molecular mechanisms of GEN in inhibiting DEX-induced osteoblast apoptosis still need further elucidation. In this article, a molecular target network of GEN against OP was screened. It was found that GEN might interact with OP by mediating PI3K/AKT pathway, which is the upstream factor in regulating autophagy. GEN exhibited protective activity against DEX-induced apoptosis by activating autophagy in vivo and in vitro. Blockage of autophagy, activation of PI3K/AKT/mTOR pathway, or inhibition of GLP-1R activity could eliminate the protective effects of GEN against DEX-induced apoptosis. Collectively, GEN ameliorated DEX-induced osteoblast apoptosis by activating autophagy through GLP-1R/PI3K/AKT/mTOR pathway.

Long non-coding RNA-small nucleolar RNA host gene 7 regulates inflammatory responses following spinal cord injury by regulating the microRNA-449a/TNF-α-induced protein 3-interacting protein 2 axis.

The current study aimed to explore the anti-inflammatory effects of long non-coding RNA-small nucleolar RNA host gene 7 (lncRNA-SNHG7) and its mechanism in spinal cord injury (SCI) models. SCI models were established both in vivo and in vitro. Reverse transcription-quantitative PCR was performed to determine the expression levels of lncRNA-SNHG7 in SCI models. Bioinformatics analysis and dual-luciferase reporter assays were carried out to confirm the interaction between lncRNA-SNHG7 with microRNA (miR)-499a and TNF-α-induced protein 3-interacting protein 2 (TNIP2). In addition, cell viability, apoptosis, and the secretion of inflammatory cytokines were assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, flow cytometric analysis, and enzyme linked immunosorbent assay (ELISA), respectively. The results showed that lncRNA-SNHG7 was markedly downregulated in the SCI model group. LncRNA-SNHG7 directly bound to miR-499a, which in turn directly targeted TNIP2. In addition, TNIP2 was significantly decreased in SCI rats and lipopolysaccharide (LPS)-treated PC-12 cells. The in vitro results in PC-12 cells revealed that lncRNA-SNHG7 overexpression attenuated neuronal cell death and SCI-mediated inflammatory responses by regulating miR-449a expression. Furthermore, miR-499a knockdown inhibited LPS-induced PC-12 cell injury by targeting TNIP2. In conclusion, lncRNA-SNHG7 modulates the apoptosis and inflammation of PC-12 cells by regulating the miR-449a/TNIP2/NF-κB signaling pathway.

Misdiagnosis of brown tumour caused by primary hyperparathyroidism: a case report with literature review.

BACKGROUND: Brown tumour is a rare tumour-like lesion of the bone, which is considered as an end-stage lesion of abnormal bone metabolism caused by persistently high parathyroid hormone (PTH) levels. Brown tumour can be found in any part of the skeleton; in some cases, it can occur in multiple bones and can be easily misdiagnosed as a metastatic tumour. CASE PRESENTATION: We report the case of a 44-year-old man who presented to the Department of Oncology in our hospital with a 2-month history of local pain in his left shoulder joint. The initial diagnosis was an aneurysmal bone cyst by biopsy, for which the patient underwent tumour resection surgery. The diagnosis of a malignant tumour was made again following postoperative pathological examination. The pathological sections and all clinical data were sent to the Department of Pathology of the First Affiliated Hospital of Sun Yat-sen University; the diagnosis made there was brown tumour. His blood PTH level was 577 pg/ml (15-65 pg/ml). Colour Doppler ultrasonography of the parathyroid gland suggested a parathyroid adenoma. For further treatment, the left parathyroid adenoma was removed by axillary endoscopic resection. Postoperatively, a pathologic examination was performed, and the diagnosis of a parathyroid adenoma was confirmed. One year after the surgery, the left humerus was completely healed, and the left shoulder joint had a good range of movement. CONCLUSIONS: In summary, histopathological diagnosis is not sufficient for the diagnosis of brown tumours. A comprehensive analysis combining clinical symptoms with findings of imaging and laboratory tests is also required. Generally, the treatment of brown tumour includes only partial or complete resection of the parathyroid glands. However, when the tumour is large, especially when it involves the joint, surgery is indispensable.

Long non-coding RNA HOTAIRincreased mechanical stimulation-induced apoptosis by regulating microRNA-221/BBC3 axis in C28/I2 cells.

Abnormal mechanical stimulation contributes to articular cartilage degeneration and osteoarthritis (OA) development. Many long noncoding RNAs (lncRNAs) are involved in mechanical force-induced cartilage degeneration. LncRNA HOTAIR (HOTAIR) has been demonstrated to increase osteoarthritis progression. However, the roles of HOTAIR in mechanical stimulation-treated chondrocytes are still unclear. In this study, we found that mechanical stimulation significantly induced apoptosis in C28/I2 cells. In addition, the expression of HOTAIR was up regulated and the expression of miR-221 was down regulated. Knockdown of HOTAIR effectively ameliorated cell apoptosis induced by mechanical stimulation. HOTAIR could interact with miR-221, which targeted to degrade BBC3. Overexpression of BBC3 could reverse the decreased apoptotic rates induced by HOTAIR knockdown. Collectively, HOTAIR promoted mechanical stimulation-induced apoptosis by regulating the miR-221/BBC3 axis in C28/I2 cells.

Giant cell tumors of the mobile spine with invasion of adjacent vertebrae: an unusual imaging finding.

BACKGROUND: Giant cell tumors of the mobile spine invasion of the adjacent vertebrae are an ignored imaging finding. METHODS: Nine patients with giant cell tumors of the mobile spine with invasion of the adjacent vertebrae confirmed by pathology were enrolled. Eight patients had pure giant cell tumors (GCTs), while one patient also had an aneurysmal bone cyst. All patients underwent conventional computed tomography, three-dimensional reconstruction, and conventional magnetic resonance imaging, while seven patients also underwent post-contrast magnetic resonance imaging. RESULTS: All patients showed GCTs of the mobile spine that arose from the vertebral body and extended to the vertebral arch. The tumors showed soft-tissue attenuation with no evidence of a mineralized matrix. Pathological fracture was seen in five patients. The margin of the original tumor showed partial sclerosis in four patients and involved an adjacent vertebral body with a sclerotic rim in two patients. The tumors showed a homogeneous and similar signal intensity to the normal spinal cord on T1WI (T1-weighted image) in five patients. The cystic area of the tumors was hyperintense on T2WI in the remaining four patients, while one patient showed hemorrhage that was hyperintense on T1WI. The solid components of the GCTs show marked enhancement in all cases, while the cystic area of the tumors was observed without enhancement on contrast-enhanced images in four patients. Bone destruction of the adjacent vertebral body showed a homogeneous signal on T1WI and T2WI and marked enhancement on contrast-enhanced images. CONCLUSIONS: Giant cell tumors of the mobile spine with invasion into adjacent vertebrae are an unusual imaging finding. Radiologists should be familiar with this imaging characteristic.

Single Posterior Approach versus Combined Anterior and Posterior Approach in the Treatment of Spinal Tuberculosis: A Meta-Analysis.

BACKGROUND: Spinal tuberculosis is the most common form of tuberculosis affecting bone and often needs surgical treatment. Single anterior, single posterior, and combined anterior and posterior approaches are the 3 most commonly used approaches in surgical treatment. Clinically, the choice of optimal surgical approach remains controversial. The purpose of this meta-analysis was to evaluate clinical efficacy of single posterior approach versus combined anterior and posterior approach. METHODS: Studies comparing surgical treatment of spinal tuberculosis by single posterior approach versus combined anterior and posterior approach were identified in a literature search conducted from study inception to July 2020. Selection of studies, extraction of data, and evaluation of bias risk of studies were performed independently by 2 authors, and meta-analysis was conducted using RevMan 5.3 software. RESULTS: The meta-analysis included 15 studies and 793 spinal tuberculosis cases. Single posterior approach was used in 397 patients, and combined anterior and posterior approach was used in 396 patients. There were no statistical differences in visual analog scale score (P = 0.51), correction of Cobb angle (P = 0.14), neurological improvement (P = 0.71), erythrocyte sedimentation rate (P = 0.32), C-reactive protein after operation (P = 0.81), and loss of correction at final follow-up (P = 0.44) between approaches. Single posterior approach was associated with less intraoperative hemorrhage (P < 0.00001), shorter operative time (P < 0.00001), shorter length of hospital stay (P < 0.00001), and fewer complications (P < 0.00001). Combined anterior and posterior approach was associated with shorter fusion time (P = 0.04). CONCLUSIONS: Both approaches can achieve satisfactory clinical outcomes. Posterior-only approach can safely and effectively achieve lesion débridement, decompression, and stability reconstruction and maintenance with advantages of less invasive surgery, less bleeding, shorter surgery time and hospital stay, and fewer complications and seems to be superior to combined posterior-anterior approach.

Dynesys system vs posterior decompression and fusion for the treatment of lumbar degenerative diseases.

BACKGROUND: The Dynesys dynamic stabilization system is an alternative to rigid instrumentation and fusion for the treatment of lumbar degenerative disease. The purpose of this study is to evaluate the clinical efficacy between Dynesys and posterior decompression and fusion for lumbar degenerative diseases. METHODS: The computer was used to retrieve the Cochrane library, Medline, Embase, CNKI, Wanfang database and Chinese biomedical literature database; and the references and main Chinese and English Department of orthopedics journals were manually searched. All the prospective or retrospective comparative studies on the clinical efficacy and safety of Dynesys and posterior decompression and fusion were collected, so as to evaluate the methodological quality of the study and to extract the data. The RevMan 5.2 software was used for data analysis. RESULTS: A total of 17 studies were included in the meta-analysis. There were no significant differences in Oswestry disability index and visual analogue score for leg pain, visual analogue score for back pain, L2-S1 ROM between Dynesys and fusion group. Operation time, blood loss, length of stay and complications in the Dynesys group were significantly less than that in the fusion group. Adjacent-segment degeneration in the fusion group was significantly higher than that in the Dynesys group. In addition, postoperative operated segment ROM was significantly less in the fusion group as compared to the Dynesys group. CONCLUSIONS: Our meta-analysis suggests that Dynesys system acquires comparable clinical outcomes compared to fusion in the treatment of lumbar degenerative diseases. Moreover, compared with fusion, Dynesys could remain ROM of surgical segments with less operation time, blood loss, length of stay, adjacent-segment degeneration, and lower complication. Further studies with large samples, long term follow up and well-designed are needed to assess the two procedures in the future.

Hirayama Disease Treated by Anterior Cervical Diskectomy and Fusion: Case Report and Literature Review.

OBJECTIVE: We present the case of a 19-year-old boy who had the classic radiologic and clinical presentations of Hirayama disease treated with anterior cervical diskectomy and fusion (ACDF). We also propose ACDF as promising surgery for the treatment of Hirayama disease. Hirayama disease is an initially progressive disease caused by cervical neck flexion compressing the anterior horns of the lower cervical spinal cord. CASE DESCRIPTION: Our patient presented with an insidious, progressive weakness in his right hand, which had been ongoing for 1 year. Physical examination revealed various degrees of right forearm and hand muscle wasting, and decreased right hand extend power with motor grade Ш. Cervical flexed magnetic resonance imaging showed a spinal cord was being compressed-most noticeably at the level of the fifth cervical vertebral body-and that the dorsal epidural space was abnormally expanding. The patient underwent ACDF at the C4-6 level. The pain and paresthesia improved immediately after the surgery. His motor grade improved immediately after the operation, and there were improvements of a modest reversal of muscle wasting at 1 year postoperatively. CONCLUSIONS: ACDF could be considered as an effective treatment option for the treatment of Hirayama disease. Our patient's finger function improved. Therefore we believe that anterior fusion might be the best choice of treatment.

Heat-air-moisture coupled model for radon migration in a porous media.

Radon is one of the main causes of environmental pollution and lung cancer. The precipitation of radon from porous media is affected by the coupling of heat and moisture, which has not been considered in the existing knowledge. We present a model for predicting radon migration in porous media. This model combines the heat-air-moisture (HAM) coupling model of porous media with a radon migration model to establish three-dimensional partial differential equations for steady-state radon migration under HAM coupling conditions. The finite element method (FEM) was used to obtain a numerical solution. Experimental verification showed that the model had high calculation accuracy; the calculated maximum relative error did not exceed 15%. The results of the model were compared with the results of a conventional model that does consider the coupling of heat and humidity; the results showed significant differences in the radon concentrations and radon flux distribution curves for the two models. The newly developed model revealed that there is a significant coupling effect between migration and the distribution of the temperature field, the humidity field, and radon flux in unsaturated porous media. The radon exhalation rate on the surface of porous media increases linearly with the increase of permeability. The exhalation rate decreased exponentially with the increase in relative humidity. When the trend of the temperature gradient was consistent with the concentration gradient, the radon exhalation rate decreased linearly with the increase in temperature gradient. We establish a new model to study the radon migration in porous media under the coupling of heat and moisture. The model provides a theoretical basis for an effective and accurate analysis of the impact of radon exhalation on the environment.

[C/EBP homologous protein-mediated endoplasmic reticulum stress-related apoptosis pathway is involved in abdominal aortic constriction-induced myocardium hypertrophy in rats.].

Endoplasmic reticulum stress (ERS) is an adaptive process in response to circumstantial changes, but excessive and/or prolonged ERS can induce cell apoptosis. C/EBP homologous protein (CHOP) is a very important marker participating in ERS-associated cell apoptosis, while the role of the myocyte apoptosis induced by CHOP remains unclear in the development of hypertrophy. The present study aimed to investigate the effect of CHOP-mediated ERS-associated apoptosis on myocardial hypertrophy induced by abdominal aortic constriction in rats. Healthy male Wistar rats were randomly divided into model group (n=45) and control group (n=40). The rats in model group received abdominal aortic constriction. Hemodynamic changes, whole heart weight/body weight (HW/BW) and left ventricular weight/body weight (LVW/BW) were measured on 1 d, 3 d, 7 d, 14 d and 28 d after surgery, respectively. The mRNA expression of glucose-regulated protein 78 (GRP78), calreticulin (CRT) and CHOP, which are important markers of ERS, were detected by RT-PCR, and Western blot was used to assess the protein level of GRP78, CRT, CHOP, and apoptosis-associated proteins, Bax and Bcl-2. The results obtained were as follows. Compared with control group, the blood pressure, LVW/BW, and HW/BW of rats in model group increased significantly and cardiac function enhanced compensatively on 7 d after surgery, and increased progressively during the experiment. As early as 1 d after surgery, the mRNA level of CRT in model group increased by 136% (P< 0.01) compared with control, while the protein expression increased by 69.2% on 7 d after surgery (P<0.01). Both mRNA and protein expression of GRP78 increased by 20% and 186% (P<0.01) respectively on 7 d after surgery, and the expression sustained high level during the experiment afterwards. Correlation analysis indicated a positive correlation between +dp/dt(max) and CRT protein expression (r=0.780, P<0.01) as well as GRP78 protein expression (r=0.694, P<0.01). Prolonged ERS triggered myocyte apoptosis, as both the mRNA and protein level of CHOP in model group increased by 22.2% (P<0.01) and 76.0% (P<0.01) respectively compared with control on 7 d after hypertrophy (14 d after surgery), and meanwhile, the protein expression of pro-apoptotic Bax increased by 41.1% (P<0.01) and anti-apoptotic Bcl-2 protein expression decreased by 25.5% (P<0.01). Correlation analysis indicated a positive correlation between CHOP and Bax expression (r=0.654, P<0.01), and a negative correlation between CHOP and Bcl-2 expression (r=-0.671, P<0.01). These results suggest that abdominal aortic constriction induces a significant up-regulation in ER molecular chaperones at early stage of post-surgery, indicating that ERS response is activated in the rat heart; while prolonged ERS could lead to myocyte apoptosis, and CHOP-mediated ERS-associated apoptosis may contribute to myocardial hypertrophy. We speculate that cell apoptosis may take part in the regulation of myocardial hypertrophy and heart failure, and determine the progression of decompensated hypertrophy.