Objective To evaluate the role of calcium/calmodulin-dependent protein kinase Ⅱ (CaMK Ⅱ) in the up-regulation of expression of Cav3.2 T-type calcium channels in spinal cord in a rat model of neuropathic pain (NP).Methods Forty-eight male Sprague-Dawley rats,aged 3 months,weighing 220-250 g,were randomly divided into 6 groups (n =8 each)∶ sham operation group (group S),group NP,dimethyl sulfoxide group (group D) and different concentrations of a specific CaMK Ⅱ inhibitor KN93 groups (groups K1-3).NP was produced by chronic compression of dorsal root ganglion.The rats in groups D and K1-3 received a single intrathecal injection of dimethyl sulfoxide and KN93 15,30,60 nmol/L (10 μl),respectively,on 5th day after NP.Paw withdrawal threshold to von Frey filament stimulation (MWT) and paw withdrawal latency to thermal nociceptive stimulus (TWL) were measured before NP,before intrathecal injection on 5th day after NP,and at 30 and 60 min and 3,6 and 8 h after intrathecal injection on 5th day after NP (T1-7).The rats were sacrificed after the measurement of pain threshold at T7 and their lumbar enlargements were removed to detect the expression of Cav3.2 mRNA and protein using Western blot and RT-PCR.Results Compared with group S,MWT was significantly decreased,TWL was shortened and the expression of Cav3.2 mRNA and protein was up-regulated in NP,D and K1-3 groups (P ＜ 0.05).Compared with NP group,MWT was significantly increased,TWL was prolonged and the expression of Cav3.2 mRNA and protein was down-regulated in a concentration-dependent manner in K1-3 groups (P ＜ 0.05),and no significant change was found in the parameters mentioned above in group D (P ＞ 0.05).Conclusion CaMK Ⅱ is involved in the development and maintenance of chronic NP by up-regulating the expression of Cav3.2 T-type calcium channels in rat spinal cord.

OBJECTIVETo investigate the effect of KN93, a calmodulin-dependent protein kinase II (CaMK II) inhibitor, on SH-SY5Y cell injury induced by bupivacaine hydrochloride.

METHODSSH-SY5Y cells exposed for 24 h to 1 mmol/L KN93, 1 mmol/L bupivacaine hydrochloride, or both were examined for morphological changes and Cav3.1 protein expressions using Western blotting. The vitality and apoptosis rate of the cells at different time points during the exposures were assessed with MTT assay and flow cytometry, respectively.

RESULTSBupivacaine hydrochloride exposure caused obvious cell morphologial changes, reduced cell viability, increased cell apoptosis, and enhanced Cav3.1 protein expression. All these changes were partly reversed by treatment of the cells with 1 mmol/L KN93.

CONCLUSIONSCaMKII may play a role in bupivacaine hydrochloride-induced SH-SY5Y cells injury, which is related with upregulated Cav3.1 protein expression.

Apoptosis ; Bupivacaine ; adverse effects ; Calcium Channels, T-Type ; metabolism ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; antagonists & inhibitors ; metabolism ; Cell Line ; Cell Survival ; Humans ; Up-Regulation

Objective Evaluation of the efficacy of high-frequency repetitive transcranial magnetic stimulation for chronic disturbance of consciousness after severe craniocerebral injury based on magnetic resonance spectroscopy.Methods The clinical data of 106 patients with chronic disturbance of consciousness after severe craniocerebral injury from January 2018 to December 2022 were retrospectively analyzed,and they were divided into control group(conventional rehabilitation treatment)and observation group(high frequency repetitive transcranial magnetic stimulation treatment)by propensity score matching method(1∶1),with 53 cases in each group.Both groups were examined by magnetic resonance spectroscopy(MRS)before and after treatment.The brain metabolic indexes[N-acetyl aspartate(NAA)/creatine(Cr)value,choline complex(Cho)/Cr value],Glasgow coma scale(GCS)score,electroencephalogram(EEG)grading,coma recovery scale(CRS-R)score,brainstem auditory evoked potential(BAEP)grading,upper limb sensory evoked potential(SSEP)grading and Cerebral blood flow perfusion index[cerebral blood volume(CBV),mean transit time(MTT),cerebral blood flow(CBF)]were compared between the two groups.Results After treatment,the NAA/Cr values of the thalamus and brainstem in the two groups increased,while the Cho/Cr values decreased,and the levels of brain metabolic indexes in the observation group were signifi-cantly better than those in the control group(P<0.05).The two groups'GCS score and CRS-R score increased,and the improvement of the observation group was better than that of the control group(P<0.05).The BAEP grading,EEG grading,and SSEP grading of the two groups improved,and those of the observation group were better than the control group(P<0.05).The CBF and CBV of the two groups increased,and MTT decreased,and the level of cere-bral blood perfusion index in the observation group was better than that in the control group(P<0.05).Conclusion High frequency repetitive transcranial magnetic stimulation has a significant effect on the recovery of patients with chronic consciousness disorders after severe craniocerebral injury.The mechanism may be related to improving the blood flow velocity of brain tissue and metabolism in the brain.