Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Objective To explore the mechanism of the therapy of promoting blood circulation and nourishing yin(PBCNY)in improving spermatogenesis in rats with varicocele based on Bcl-2/Bax pathway.Methods Thirty 8-week-old male SD rats were randomly divided into six groups(five rats per group):sham,model,levocarnitine(1.0 g/kg),and PBCNY low-dose(5.2 g/kg),PBCNY medium-dose(10.4 g/kg),and PBCNY high-dose(20.8 g/kg)groups.Apart from the sham group,all the groups were built a varicocele model by the classical Turner method.After 4 weeks,the sham group and model group were gavaged with normal saline,and the remaining groups were given with levocarnitine or different doses of PBCNY decoction once a day for 4 weeks.At the end of gavage,the sperm quality of rats in each group was detected by a computer-assisted sperm analyzer,and HE staining was used to observe the testicular tissue morphology of rats in each group and performed with Johnsen score.TUNEL method was used to detect apoptosis,RT-qPCR was used to detect Bcl-2 and Bax mRNA expression,and immunohistochemical method was used to detect cytochrome C protein expression.Results Compared to the sham group,sperm total count,motility rate and percentage of sperm with grade(a+b)motility were lower in the model group of rats(P<0.05).HE staining showed disturbed arrangement of seminiferous tubules in the testicular tissue with significant changes and decreased Johnsen score(P<0.05).The result of TUNEL assay showed that the apoptosis rate was increased in the model group(P<0.05).Bax mRNA expression was increased in testicular tissue(P<0.05).The result of immunohistochemistry showed that the positive expression of cytochrome C was increased in the model group(P<0.05).Compared with the model group,the rat sperm total count in the PBCNY medium-dose group,motility rate in the PBCNY low-and medium-dose groups,and percentage of sperm with grade(a+b)motility in the PBCNY low-dose group increased(P<0.05);the pathological structure of rat testis had different degrees of improvement,and Johnsen score increased in the PBCNY medium-dose group(P<0.05);the apoptosis rate of testicular cells decreased in the levocarnitine group and all doses of PBCNY groups(P<0.05);the expression of Bcl-2 mRNA increased in the PBCNY low-dose and high-dose groups(P<0.05),and the expression of Bax mRNA decreased in the levocarnitine group and the PBCNY medium-dose group(P<0.05);the positive expression of cytochrome C decreased in the PBCNY medium-dose group(P<0.05).Conclusion The therapy of PBCNY can improve sperm quality,repair damaged testicular tissue structure and improve spermatogenic function in rats with varicocele,and its mechanism of action may be related to the activation of Bcl-2/Bax pathway and inhibition of cell apoptosis.

Background China's automobile manufacture is a labor-intensive industry, and most of the welding tasks are manual operations. It is often necessary to observe the solder joints during operation, and there are many adverse health outcome-related factors involved in the work process. However, the research on the prevalence and risk factors of work-related musculoskeletal disorders (WMSDs) in the upper back of welders is still insufficient. Objective To explore the prevalence and risk factors of WMSDs in the upper back of welders from an automobile factory. Methods This was a cross-sectional study. A cluster random sampling method was used to select 972 electric welders from an automobile factory as the study subjects. The Musculoskeletal Disorders Questionnaire was used to estimate the prevalence of WMSDs in the upper back in the past year. Results The prevalence rate of WMSDs in the upper back in the welders was 42.2% (410/972). The positive rates of studied occupational risk factors were 72.5% (705/972) for maintaining same posture for a long time, 71.8% (698/972) for bending and twisting for a long time, and 64.7% (629/972) for repetitive trunk movements. The univariate analysis showed that the prevalence rates of WMSDs were significantly different among workers categorized by gender, working age, twisting and/or bending for a long time, working in the same position for a long time, lifting heavy objects in an uncomfortable position, repetitive trunk movements, being unable to exert energy due to discomfort, work involving cold or temperature changes, personnel shortage, no rest between work, working hours per week, and working in an uncomfortable position (P<0.05). The results of multiple logistic regression indicated that female, working in the same position for a long time, working in an uncomfortable position (frequently), lifting heavy objects in an uncomfortable position, and being unable to exert energy due to discomfort were associated with higher risks of reporting WMSDs in the upper back (OR=2.37, 1.46, 1.76, 1.44, and 1.50, respectively, P<0.05); the risk of reporting WMSDs in the upper back increased by 95%, 157%, and 196% for every 10 h increase in weekly working hours (41-50 h, 51-60 h, ≥61 h vs ≤40 h); adequate rest time was associated with a lower risk for WMSDs in the upper back (OR=0.70, 95%CI: 0.49-0.98). Conclusion The prevalence rate of WMSDs in the upper back of welders in the automobile factory is high, and many occupational risk factors are involved. Measures should be taken for intervention and prevention.

Objective To investigate the effect of esmolol pretreatment on Toll like receptor-4 (TLR4)/nuclear factor-kappa-B (NF-кB) pathway in rats with repeated cerebral ischemia/reperfusion (IR) injury. Methods Forty-eight adult male Sprague-Dawley rats were randomly allocated into sham-operated group, IR group and esmolol group (n=16). Rats in the IR group and esmolol group were injected intravenously with esmolol at a dose of 200 g/(kg?min) or normal saline for one h before surgery, and then, bilateral common carotid arteries were clipped to establish the repeated IR injury models. Bilateral common carotid arteries in rats of sham-operated group were only isolated but not clipped, and injected intravenously with normovolemic normal saline for one h. Learning and memory abilities of rats were measured by Morris water maze test before, and one, 3 and 7 d after surgery. Rats were euthanized and hippocampus tissues were excised. The wet to dry (W/D) ratio of the hippocampus was tested. The permeability of blood-brain barrier was determined by Evans blue (EB) method. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6 and IL-1β in the hippocampus were tested by enzyme linked immunosorbent assay (ELISA). The NF-кB p65 and TLR4 mRNA expressions in the hippocampus were determined by reverse transcription-polymerase chain reaction (RT-PCR). The NF-кB p65 and TLR4 protein expressions in hippocampus were detected by Western blotting. Results As compared with those in the sham-operated group, the escape latency was significantly prolonged and swimming distance was signficantly longer in rats of IR group one, 3 and 7 d after surgery (P<0.05), the W/D ratio of the hippocampus and the content of EB in brain tissues were significantly increased in the IR group (P<0.05), the levels of TNF-α, IL-6 and IL-1β in hippocampus were significantly increased in the IR group (P<0.05), and the NF-кB p65 or TLR4 mRNA and protein expressions in the hippocampus of IR group were statistically higher (P<0.05). As compared with IR group, the escape latency and swimming distance of rats in the esmolol group were significantly shortened one, 3 and 7 d after surgery (P<0.05), the W/D ratio of the hippocampus and content of EB in brain tissues of esmolol group were significantly decreased (P<0.05), the levels of TNF-α, IL-6 and IL-1β in the hippocampus of esmolol group were signficantly lower(P<0.05), and the NF-кB p65 or TLR4 mRNA and protein expressions in hippocampus of esmolol group were statistically lower in the esmolol group (P<0.05). Conclusion Esmolol preconditioning can alleviate cerebral injury and improve learning and memory abilities of rats with repeated cerebral IR injury, which may be involved in alleviating inflammation and suppressing TLR4/NF-кB pathway.