Acute sleep deprivation (ASD) and cardioprotection: Impact of ASD on oxytocin-mediated sympathetic nervous activation preceding myocardial infarction

INTRODUCTION

This study explored how acute sleep deprivation (ASD) before myocardial ischemia influences oxytocin release from paraventricular (PVN) neurons and its correlation with sympathetic nervous system (SNS) activity post-acute sleep loss, impacting subsequent left ventricular (LV) remodeling following myocardial infarction (MI).

METHODS

The study was conducted in two phases: induction of ASD, inducing MI, blood sampling, euthanizing animals and collecting their heart and brain for histological and gene expression evaluations. The animals in first and second phase were euthanized 24 h and 14 days after MI, respectively.

RESULTS

Pre-MI ASD, accompanied by increased serum epinephrine levels within 24 h of MI, upregulated oxytocin and cFos expression in the PVN. Also, pre-MI ASD resulted in decreased serum PAB levels 14 days post-MI (P < 0.001). While notable echocardiographic changes were seen in MI versus sham groups, ASD demonstrated protective effects. This was evidenced by reduced infarct size, elevated TIMP1, MMP2, and MMP9 in the LV of SD + MI animals versus MI alone (P < 0.05). Additionally, histological analysis showed reduced LV fibrosis in pre-MI ASD subjects (P < 0.05).

CONCLUSION

Our study supports the notion that activation of oxytocin neurons within the PVN subsequent to ASD interacts with autonomic centers in the central nervous system. This enhanced sympathetic outflow to the heart prior to MI triggers a preconditioning response, thereby mediating cardioprotection through decreased oxidative stress biomarkers and regulated extracellular matrix (ECM) turnover.

The effect of heart rate variability biofeedback in patients with acute coronary syndrome: A protocol for systematic review and meta-analysis

BACKGROUND

Acute coronary syndrome (ACS), the acute manifestation of ischemic heart disease, remains a major cause of morbidity and mortality worldwide. Soon after ACS, autonomic imbalance acts to preserve the proper functioning of the cardiovascular system and consequently of the whole body. In this study, we perform a protocol for systematic review and meta-analysis to evaluate the efficacy of heart rate variability biofeedback in improving the prognosis in patients with ACS.

METHODS

The protocol of this review was registered in PROSPERO (CRD42022379184). Meanwhile, it will be reported follow the guidelines of the preferred reporting items for systematic reviews and meta-analyses protocol. We will search 3 foreign electronic databases (Cochrane Library, Embase, Pubmed) and 4 Chinese electronic databases (China National Knowledge Infrastructure, WangFang Database, Chinese Biomedical Literature Database and Chinese Scientific Journal Database) to collect potential studies from their inceptions to December 2022. Risk of bias will be assessed according to the Cochrane Risk of Bias Tool. Data synthesis and statistical analysis will be performed using the RevMan 5.3 (The Nordic Cochrane Centre, The Cochrane Collaboration, Denmark) software.

RESULTS

The results of this systematic review will be published in a peer-reviewed journal.

CONCLUSION

This systematic review will provide high quality evidence to assess the efficacy of heart rate variability biofeedback in patients with ACS.

Therapeutic target and clinical impact of day-to-day blood pressure variability in hypertensive patients with covid-19

Blood pressure variability (BPV) is essential in hypertensive patients and is frequently associated with organ damage. As of today, hypertension is still the most common comorbidity in COVID-19, but the impact of BPV and the therapeutic target of BPV on outcomes in COVID-19 patients with hypertension remain unclear. Therefore, this study investigated the relationship between BPV and severity of COVID-19, in-hospital mortality, hypertensive status, and efficacy of antihypertensives in suppressing hypertensive covid-19 patient BPV. This cohort retrospective study enrolled 351 patients hospitalized with COVID-19. Subjects were classified according to the severity of COVID-19, the presence of hypertension, and their BPV status. During hospitalization, mean arterial pressure (MAP) was measured at 6 a.m. and 6 p.m., and BPV was calculated as the coefficient of variation of MAP (MAPCV). MAPCV values above the median were defined as high BPV. In addition, we compared the hypertensive status, COVID-19 severity, in-hospital mortality, and antihypertensive agents between the BPV groups. The mean age was 53.85 ± 18.84 years old. Hypertension was significantly associated with high BPV with prevalence ratio (PR) = 1.38 (95% CI = 1.13-1.70; p = 0.003) or severe COVID-19 (PR = 1.39; 95% CI = 1.09-1.76; p = 0.005). In laboratory findings, high BPV group had lower Albumin, higher WBC, serum Cr, CRP, and creatinine to albumin ratio. High BPV status also significantly increased risk of mortality (HR = 2.30; 95% CI = 1.73-3.86; p < 0.001). Patients with a combination of severe COVID-19 status, hypertension, and high BPV status had the highest risk of in-hospital mortality (HR = 3.51; 95% CI = 2.32-4.97; p < 0.001) compared to other combination status groups. In COVID-19 patients with hypertension, combination therapy with calcium channel blockers (CCB) as well as CCB monotherapy significantly develop low BPV (PR = 2.002; 95 CI% = 1.33-3.07; p = 0.004) and low mortality (HR = 0.17; 95% CI = 0.05-0.56; p = 0.004). Hypertensive status and severe COVID-19 were significantly associated with high BPV, and these factors increased in-hospital mortality. CCBs might be antihypertensive agents that potentially effectively suppressing BPV and mortality in COVID-19 patients.

Tracking peripheral vascular function for six months in young adults following SARS-CoV-2 infection

SARS-CoV-2 infection is known to instigate a range of physiologic perturbations, including vascular dysfunction. However, little work has concluded how long these effects may last, especially among young adults with mild symptoms. To determine potential recovery from acute vascular dysfunction in young adults (8 M/8F, 21 ± 1 yr, 23.5 ± 3.1 kg⋅m-2 ), we longitudinally tracked brachial artery flow-mediated dilation (FMD) and reactive hyperemia (RH) in the arm and hyperemic response to passive limb movement (PLM) in the leg, with Doppler ultrasound, as well as circulating biomarkers of inflammation (interleukin-6, C-reactive protein), oxidative stress (thiobarbituric acid reactive substances, protein carbonyl), antioxidant capacity (superoxide dismutase), and nitric oxide bioavailability (nitrite) monthly for a 6-month period post-SARS-CoV-2 infection. FMD, as a marker of macrovascular function, improved from month 1 (3.06 ± 1.39%) to month 6 (6.60 ± 2.07%; p < 0.001). FMD/Shear improved from month one (0.10 ± 0.06 AU) to month six (0.18 ± 0.70 AU; p = 0.002). RH in the arm and PLM in the leg, as markers of microvascular function, did not change during the 6 months (p > 0.05). Circulating markers of inflammation, oxidative stress, antioxidant capacity, and nitric oxide bioavailability did not change during the 6 months (p > 0.05). Together, these results suggest some improvements in macrovascular, but not microvascular function, over 6 months following SARS-CoV-2 infection. The data also suggest persistent ramifications for cardiovascular health among those recovering from mild illness and among young, otherwise healthy adults with SARS-CoV-2.

Bromocriptine-QR Therapy Reduces Sympathetic Tone and Ameliorates a Pro-Oxidative/Pro-Inflammatory Phenotype in Peripheral Blood Mononuclear Cells and Plasma of Type 2 Diabetes Subjects

Bromocriptine-QR is a sympatholytic dopamine D2 agonist for the treatment of type 2 diabetes that has demonstrated rapid (within 1 year) substantial reductions in adverse cardiovascular events in this population by as yet incompletely delineated mechanisms. However, a chronic state of elevated sympathetic nervous system activity and central hypodopaminergic function has been demonstrated to potentiate an immune system pro-oxidative/pro-inflammatory condition and this immune phenotype is known to contribute significantly to the advancement of cardiovascular disease (CVD). Therefore, the possibility exists that bromocriptine-QR therapy may reduce adverse cardiovascular events in type 2 diabetes subjects via attenuation of this underlying chronic pro-oxidative/pro-inflammatory state. The present study was undertaken to assess the impact of bromocriptine-QR on a wide range of immune pro-oxidative/pro-inflammatory biochemical pathways and genes known to be operative in the genesis and progression of CVD. Inflammatory peripheral blood mononuclear cell biology is both a significant contributor to cardiovascular disease and also a marker of the body’s systemic pro-inflammatory status. Therefore, this study investigated the effects of 4-month circadian-timed (within 2 h of waking in the morning) bromocriptine-QR therapy (3.2 mg/day) in type 2 diabetes subjects whose glycemia was not optimally controlled on the glucagon-like peptide 1 receptor agonist on (i) gene expression status (via qPCR) of a wide array of mononuclear cell pro-oxidative/pro-inflammatory genes known to participate in the genesis and progression of CVD (OXR1, NRF2, NQO1, SOD1, SOD2, CAT, GSR, GPX1, GPX4, GCH1, HMOX1, BiP, EIF2α, ATF4, PERK, XBP1, ATF6, CHOP, GSK3β, NFkB, TXNIP, PIN1, BECN1, TLR2, TLR4, TLR10, MAPK8, NLRP3, CCR2, GCR, L-selectin, VCAM1, ICAM1) and (ii) humoral measures of sympathetic tone (norepinephrine and normetanephrine), whole-body oxidative stress (nitrotyrosine, TBARS), and pro-inflammatory factors (IL-1β, IL-6, IL-18, MCP-1, prolactin, C-reactive protein [CRP]). Relative to pre-treatment status, 4 months of bromocriptine-QR therapy resulted in significant reductions of mRNA levels in PBMC endoplasmic reticulum stress-unfolded protein response effectors [GRP78/BiP (34%), EIF2α (32%), ATF4 (29%), XBP1 (25%), PIN1 (14%), BECN1 (23%)], oxidative stress response proteins [OXR1 (31%), NRF2 (32%), NQO1 (39%), SOD1 (52%), CAT (26%), GPX1 (33%), GPX4 (31%), GCH1 (30%), HMOX1 (40%)], mRNA levels of TLR pro-inflammatory pathway proteins [TLR2 (46%), TLR4 (20%), GSK3β (19%), NFkB (33%), TXNIP (18%), NLRP3 (32%), CCR2 (24%), GCR (28%)], mRNA levels of pro-inflammatory cellular receptor proteins CCR2 and GCR by 24% and 28%, and adhesion molecule proteins L-selectin (35%) and VCAM1 (24%). Relative to baseline, bromocriptine-QR therapy also significantly reduced plasma levels of norepinephrine and normetanephrine by 33% and 22%, respectively, plasma pro-oxidative markers nitrotyrosine and TBARS by 13% and 10%, respectively, and pro-inflammatory factors IL-18, MCP1, IL-1β, prolactin, and CRP by 21%,13%, 12%, 42%, and 45%, respectively. These findings suggest a unique role for circadian-timed bromocriptine-QR sympatholytic dopamine agonist therapy in reducing systemic low-grade sterile inflammation to thereby reduce cardiovascular disease risk.

Predictive Value of Increased Perioperative Heart Rate for All-Cause Mortality After Cardiac Surgery: A Systematic Review and Meta-Analysis

Background: Accumulated studies have revealed that heart rates are associated with all-cause mortality in cardiac surgery patients, but the results remain controversial. This meta-analysis aimed to evaluate the predictive value of increased perioperative heart rate for all-cause mortality after cardiac surgery. Methods: We searched PubMed, Embase, Web of Science, and Cumulative Index of Nursing and Allied Health Literature (CINAHL) databases for studies from inception to October 11, 2021. Two researchers independently screened the studies. Titles, authors, publication years, and hazard ratios were extracted. We used a random-effects model to combine the HRs and 95% confidence intervals. Several subgroup analyses were conducted. Statistical significance was set at p < .05. Results: Eleven studies were included in the meta-analysis of 33,849 patients and 3166 (9.4%) deaths. The HR of higher perioperative heart rates was 2.09 (95% CI 1.53-2.86, p < .001, I² = 81%). The HR with a 10-bpm increase in preoperative heart rate was 1.19 (95% CI 1.11-1.26, p < .001, I² = 51%). Subgroup analysis showed patients with higher preoperative heart rates had an HR of 1.88 (95% CI 1.51-2.34, p < .001, I² = 0%), and patients with a higher postoperative heart rate had an HR of 2.29 (95% CI 1.28- 4.09, p < .0001, I² = 91%) compared to patients with lower postoperative heart rates. Conclusion: Increased perioperative heart rate is associated with all-cause mortality in patients undergoing cardiac surgery.

The association between 24-h blood pressure variability and major adverse cardiac events (MACE) in hospitalized patients with acute myocardial infarction: a retrospective cohort study

BACKGROUND

Acute myocardial infarction (AMI) is major cardiovascular disease that causes high morbidity and mortality. In AMI, ischemia and necrosis affected some cardiomyocytes leading to a decrease in myocardial contractility which is followed by an acute proinflammation reaction and increased sympathetic tone. Meanwhile, high blood pressure variability (BPV) causing an increased left ventricular workload, heart rate, myocardial oxygen demand and induces proinflamations and endothelial dysfunction. Therefore a high BPV and its associated pathological effects are likely to aggravate the physiological function of the heart and affect the emergence of acute cardiac complications in AMI patients. This study aims to investigate the association's between short-term BPV and major adverse cardiac events (MACE) in AMI patients. This retrospective cohort study used simple random sampling to identify AMI patients who were hospitalized at Cipto Mangunkusumo National Hospital between January 2018 and December 2019. Mann Withney was performed to investigate the association between BPV and MACE.

RESULTS

The average systolic BPV value which was calculated as standard deviation (SD) and average real variability (ARV) was higher in the MACE group than in the non-MACE group. Systolic SD and systolic ARV in the MACE group were 13.28 ± 5.41 mmHg and 9.88 ± 3.81 mmHg respectively. In the non-MACE group, systolic SD and systolic ARV were 10.76 (4.59-26.17) mmHg and 8.65 (3.22-19.35) mmHg respectively. There was no significant association between BPV and MACE. However, there were significant differences between systolic SD and systolic ARV in patients with hypertension who experienced MACE and patients without hypertension who experienced MACE.

CONCLUSIONS

The BPV of AMI patients who experience MACE was higher than that of non-MACE AMI patients. There was no significant association between BPV ​​and MACE during the acute phase of AMI.

COVID-19 is getting on our nerves: sympathetic neural activity and haemodynamics in young adults recovering from SARS-CoV-2

KEY POINTS

The impact of SARS-CoV-2 infection on autonomic and cardiovascular function in otherwise healthy individuals is unknown. For the first time it is shown that young adults recovering from SARS-CoV-2 have elevated resting sympathetic activity, but similar heart rate and blood pressure, compared with control subjects. Survivors of SARS-CoV-2 also exhibit similar sympathetic nerve activity and haemodynamics, but decreased pain perception, during a cold pressor test compared with healthy controls. Further, these individuals display higher sympathetic nerve activity throughout an orthostatic challenge, as well as an exaggerated heart rate response to orthostasis. If similar autonomic dysregulation, like that found here in young individuals, is present in older adults following SARS-CoV-2 infection, there may be substantial adverse implications for cardiovascular health.

ABSTRACT

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can elicit systemic adverse physiological effects. However, the impact of SARS-CoV-2 on autonomic and cardiovascular function in otherwise healthy individuals remains unclear. Young adults who tested positive for SARS-CoV-2 (COV+; n = 16, 8 F) visited the laboratory 35 ± 16 days following diagnosis. Muscle sympathetic nerve activity (MSNA), systolic (SBP) and diastolic (DBP) blood pressure, and heart rate (HR) were measured in participants at rest and during a 2 min cold pressor test (CPT) and 5 min each at 30° and 60° head-up tilt (HUT). Data were compared with age-matched healthy controls (CON; n = 14, 9 F). COV+ participants (18.2 ± 6.6 bursts min-1 ) had higher resting MSNA burst frequency compared with CON (12.7 ± 3.4 bursts min-1 ) (P = 0.020), as well as higher MSNA burst incidence and total activity. Resting HR, SBP and DBP were not different. During CPT, there were no differences in MSNA, HR, SBP or DBP between groups. COV+ participants reported less pain during the CPT compared with CON (5.7 ± 1.8 vs. 7.2 ± 1.9 a.u., P = 0.036). MSNA was higher in COV+ compared with CON during HUT. There was a group-by-position interaction in MSNA burst incidence, as well as HR, in response to HUT. These results indicate resting sympathetic activity, but not HR or BP, may be elevated following SARS-CoV-2 infection. Further, cardiovascular and perceptual responses to physiological stress may be altered, including both exaggerated (orthostasis) and suppressed (pain perception) responses, compared with healthy young adults.

COVID-19 is getting on our nerves: sympathetic neural activity and haemodynamics in young adults recovering from SARS-CoV-2

Key points

The impact of SARS‐CoV‐2 infection on autonomic and cardiovascular function in otherwise healthy individuals is unknown.

For the first time it is shown that young adults recovering from SARS‐CoV‐2 have elevated resting sympathetic activity, but similar heart rate and blood pressure, compared with control subjects.

Survivors of SARS‐CoV‐2 also exhibit similar sympathetic nerve activity and haemodynamics, but decreased pain perception, during a cold pressor test compared with healthy controls.

Further, these individuals display higher sympathetic nerve activity throughout an orthostatic challenge, as well as an exaggerated heart rate response to orthostasis.

If similar autonomic dysregulation, like that found here in young individuals, is present in older adults following SARS‐CoV‐2 infection, there may be substantial adverse implications for cardiovascular health.

Abstract

The novel severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) can elicit systemic adverse physiological effects. However, the impact of SARS‐CoV‐2 on autonomic and cardiovascular function in otherwise healthy individuals remains unclear. Young adults who tested positive for SARS‐CoV‐2 (COV+; n = 16, 8 F) visited the laboratory 35 ± 16 days following diagnosis. Muscle sympathetic nerve activity (MSNA), systolic (SBP) and diastolic (DBP) blood pressure, and heart rate (HR) were measured in participants at rest and during a 2 min cold pressor test (CPT) and 5 min each at 30° and 60° head‐up tilt (HUT). Data were compared with age‐matched healthy controls (CON; n = 14, 9 F). COV+ participants (18.2 ± 6.6 bursts min⁻¹) had higher resting MSNA burst frequency compared with CON (12.7 ± 3.4 bursts min⁻¹) (P = 0.020), as well as higher MSNA burst incidence and total activity. Resting HR, SBP and DBP were not different. During CPT, there were no differences in MSNA, HR, SBP or DBP between groups. COV+ participants reported less pain during the CPT compared with CON (5.7 ± 1.8 vs. 7.2 ± 1.9 a.u., P = 0.036). MSNA was higher in COV+ compared with CON during HUT. There was a group‐by‐position interaction in MSNA burst incidence, as well as HR, in response to HUT. These results indicate resting sympathetic activity, but not HR or BP, may be elevated following SARS‐CoV‐2 infection. Further, cardiovascular and perceptual responses to physiological stress may be altered, including both exaggerated (orthostasis) and suppressed (pain perception) responses, compared with healthy young adults.

The impact of SARS‐CoV‐2 infection on autonomic and cardiovascular function in otherwise healthy individuals is unknown.

For the first time it is shown that young adults recovering from SARS‐CoV‐2 have elevated resting sympathetic activity, but similar heart rate and blood pressure, compared with control subjects.

Survivors of SARS‐CoV‐2 also exhibit similar sympathetic nerve activity and haemodynamics, but decreased pain perception, during a cold pressor test compared with healthy controls.

Further, these individuals display higher sympathetic nerve activity throughout an orthostatic challenge, as well as an exaggerated heart rate response to orthostasis.

If similar autonomic dysregulation, like that found here in young individuals, is present in older adults following SARS‐CoV‐2 infection, there may be substantial adverse implications for cardiovascular health.

[11C]mHED PET follows a two-tissue compartment model in mouse myocardium with norepinephrine transporter (NET)-dependent uptake, while [18F]LMI1195 uptake is NET-independent

PURPOSE

Clinical positron emission tomography (PET) imaging of the presynaptic norepinephrine transporter (NET) function provides valuable diagnostic information on sympathetic outflow and neuronal status. As data on the NET-targeting PET tracers [¹¹C]meta-hydroxyephedrine ([¹¹C]mHED) and [¹⁸F]LMI1195 ([¹⁸F]flubrobenguane) in murine experimental models are scarce or lacking, we performed a detailed characterization of their myocardial uptake pattern and investigated [¹¹C]mHED uptake by kinetic modelling.

METHODS

[¹¹C]mHED and [¹⁸F]LMI1195 accumulation in the heart was studied by PET/CT in FVB/N mice. To test for specific uptake by NET, desipramine, a selective NET inhibitor, was administered by intraperitoneal injection. [¹¹C]mHED kinetic modelling with input function from an arteriovenous shunt was performed in three mice.

RESULTS

Both tracers accumulated in the mouse myocardium; however, only [¹¹C]mHED uptake was significantly reduced by excess amount of desipramine. Myocardial [¹¹C]mHED uptake was half-saturated at 88.3 nmol/kg of combined mHED and metaraminol residual. After [¹¹C]mHED injection, a radiometabolite was detected in plasma and urine, but not in the myocardium. [¹¹C]mHED kinetics followed serial two-tissue compartment models with desipramine-sensitive K₁.

CONCLUSION

PET with [¹¹C]mHED but not [¹⁸F]LMI1195 provides information on NET function in the mouse heart. [¹¹C]mHED PET is dose-independent in the mouse myocardium at < 10 nmol/kg of combined mHED and metaraminol. [¹¹C]mHED kinetics followed serial two-tissue compartment models with K₁ representing NET transport. Myocardial [¹¹C]mHED uptake obtained from PET images may be used to assess cardiac sympathetic integrity in mouse models of cardiovascular disease.

Elevated Lipoprotein-Associated Phospholipase A2 is Valuable in Prediction of Coronary Slow Flow in Non-ST-Segment Elevation Myocardial Infarction Patients

Background Coronary flow is a determinative factor of non-ST-segment elevation myocardial infarction (NSTEMI) patients. Lipoprotein-Associated Phospholipase A2(Lp-PLA2) as a vascular specific inflammatory cytokine might relate to coronary slow flow in these patients. Methods 105 NSTEMI patients and 83 UAP patients were enrolled. Another group division was made by Lp-PLA2 tertile data. Corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) was adopted to represent coronary flow condition. Correlation analysis was made between CTFC and other clinical indicators. Multivariable regression analysis was used to identify the influential factors of coronary flow in NSTEMI patients. ROC curve was used to determine the diagnostic value of Lp-PLA2 with coronary slow flow (CSF). Results High sensitive C reactive protein (hsCRP, P < 0.01), Lp-PLA2(P < 0.01), N-terminal pro-brain natriuretic peptide (NT-proBNP, P < 0.05), mean platelet volume (MPV, P<0.05), CTFC(P < 0.05) was higher in NSTEMI than UAP patients. hsCRP(P < 0.01), MPV(P < 0.01), NT-proBNP(P < 0.01) CTFC(P < 0.01) was higher in high-Lp-PLA2 group. Lp-PLA2 and hsCRP (r = 0.22, P < 0.01), MPV (r = 0.21, P < 0.05), CTFC (r = 0.69, P < 0.01) had a positive correlation in NSTEMI group. Multivariable regression analysis showed that Lp-PLA2 could explain most part changes of CTFC in NSTEMI patients, CTFC = 0.55*Lp-PLA2+0.03*hsCRP+0.005*NT-proBNP+15.843. Lp-PLA2 was specific and sensitive in diagnosis of CSF in NSTEMI group, AUC = 0.851(95% confidence interval (CI): 0.771-0.924, P < 0.01), Cutoff=196.96ng/ml, sensitivity = 84%, specificity = 81%. Conclusions Lp-PLA2 is closely correlated with coronary flow in NSTEMI patients. Lp-PLA2 over 196.96ng/ml could be used to predict CSF in NSTEMI patients.

Dexmedetomidine attenuates pancreatic injury and inflammatory response in mice with pancreatitis by possible reduction of NLRP3 activation and up-regulation of NET expression

OBJECTIVE

Previous studies have shown that acute inflammation is associated with increased sympathetic activity, which in turn increases the inflammatory response and leads to organ damage. The present study aimed to investigate whether dexmedetomidine administration during acute pancreatitis (AP) lessens pancreatic pathological and functional injury and the inflammatory response, and to explore the underlying mechanisms.

METHODS

Mild pancreatitis was induced in mice with caerulein, and severe pancreatitis was induced with caerulein plus lipopolysaccharide (LPS). After pancreatitis induction, dexmedetomidine at 10 or 20 μg/kg was injected via the tail vein. Pancreatic pathological and functional injury was assessed by histology and serum levels of amylase and lipase, respectively. The inflammatory response was evaluated by determining serum levels of inflammatory factors. The expression of myeloperoxidase (MPO) was examined by immunohistochemistry. The expression of norepinephrine transporter (NET), NLRP3, pro-IL-1β, and interleukin (IL)-1β in pancreatic tissue was detected by Western blot and real-time PCR.

RESULTS

Dexmedetomidine at 20 μg/kg significantly attenuated pancreatic pathological injury, reduced serum levels of amylase, lipase, IL-1β, IL-6, and tumor necrosis factor (TNF)-α, and decreased the expression of MPO in pancreatic tissue in both mouse models of pancreatitis. In addition, dexmedetomidine at 20 μg/kg significantly down-regulated the expression of NLRP3, pro-IL-1β, and IL-1β in pancreatic tissue, but up-regulated the expression of NET in both mouse models.

CONCLUSION

Dexmedetomidine attenuates pancreatic injury and inflammatory response in mice with pancreatitis possibly by reducing NLRP3 activation and up-regulating NET expression.