OBJECTIVE: To evaluate the early effectiveness of local infiltration anesthesia (LIA) with compound betamethasone in total knee arthroplasty (TKA). METHODS: The clinical data of 102 patients with knee osteoarthritis who were treated by TKA and met the selection criteria between May 2022 and March 2023 were retrospectively analyzed. They were divided into control group and study group according to whether LIA preparation was added with compound betamethasone, with 51 cases in each group. There was no significant difference of baseline data, such as age, gender, body mass index, operative side, preoperative range of motion (ROM), Knee Society Score (KSS), white blood cell (WBC), and hematocrit between the two groups ( P>0.05). The intraoperative total blood loss and hidden blood loss were recorded, and WBC was recorded on the 1st, 2nd, and 3rd days after operation. Pain was assessed by visual analogue scale (VAS) score on the 1st, 2nd, and 3rd days after operation and morphine intake milligrames equivalent within 48 hours after operation. Passive ROM, maximum extension and flexion angles of knee joint were measured on the 3rd day after operation; the early postoperative complications were recorded. RESULTS: There was no significant difference in total blood loss and hidden blood loss between the two groups ( P>0.05). The postoperative pain levels in both groups were relatively mild, and there was no significant difference in VAS scores in the first 3 days after operation and in morphine intake milligrams equivalent within 48 hours after operation between the two groups ( P>0.05). The WBC in the first 3 days after operation was significantly improved in both groups ( P<0.05). The WBC in the study group was significantly higher than that in the control group on the 1st and 2nd days after operation ( P<0.05), but there was no significant difference between the two groups on the 3rd day after operation ( P>0.05). On the 3rd day after operation, the maximum extension angle of knee joint in the study group was smaller than that in the control group, while the maximum flexion angle and passive ROM of knee joint in the study group were larger than those in the control group, and the differences were significant ( P<0.05). There were 6 cases of fever and 17 cases of deep venous thrombosis in the control group, and 1 case and 14 cases in the study group, respectively. There was no poor wound healing and periprosthetic joint infection in the two groups, and there was no significant difference in the incidence of complications between the two groups ( P>0.05). CONCLUSION The application of compound betamethasone in LIA during TKA is a safe and optimal strategy to promote the early postoperative rehabilitation of patients.
Humans ; Arthroplasty, Replacement, Knee ; Anesthesia, Local ; Retrospective Studies ; Treatment Outcome ; Knee Joint/surgery* ; Osteoarthritis, Knee/surgery* ; Blood Loss, Surgical ; Morphine

The chronic use of morphine and other opioids is associated with opioid-induced hypersensitivity (OIH) and analgesic tolerance. Among the different forms of OIH and tolerance, the opioid receptors and cell types mediating opioid-induced mechanical allodynia and anti-allodynic tolerance remain unresolved. Here we demonstrated that the loss of peripheral μ-opioid receptors (MORs) or MOR-expressing neurons attenuated thermal tolerance, but did not affect the expression and maintenance of morphine-induced mechanical allodynia and anti-allodynic tolerance. To confirm this result, we made dorsal root ganglia-dorsal roots-sagittal spinal cord slice preparations and recorded low-threshold Aβ-fiber stimulation-evoked inputs and outputs in superficial dorsal horn neurons. Consistent with the behavioral results, peripheral MOR loss did not prevent the opening of Aβ mechanical allodynia pathways in the spinal dorsal horn. Therefore, the peripheral MOR signaling pathway may not be an optimal target for preventing mechanical OIH and analgesic tolerance. Future studies should focus more on central mechanisms.
Humans ; Morphine/pharmacology* ; Hyperalgesia/metabolism* ; Analgesics, Opioid/pharmacology* ; Neurons/metabolism* ; Signal Transduction

Opioid use disorder (OUD) has become a considerable global public health challenge; however, potential medications for the management of OUD that are effective, safe, and nonaddictive are not available. Accumulating preclinical evidence indicates that antagonists of the dopamine D₃ receptor (D₃R) have effects on addiction in different animal models. We have previously reported that YQA14, a D₃R antagonist, exhibits very high affinity and selectivity for D₃Rs over D₂Rs, and is able to inhibit cocaine- or methamphetamine-induced reinforcement and reinstatement in self-administration tests. In the present study, our results illustrated that YQA14 dose-dependently reduced infusions under the fixed-ratio 2 procedure and lowered the breakpoint under the progressive-ratio procedure in heroin self-administered rats, also attenuated heroin-induced reinstatement of drug-seeking behavior. On the other hand, YQA14 not only reduced morphine-induced expression of conditioned place preference but also facilitated the extinguishing process in mice. Moreover, we elucidated that YQA14 attenuated opioid-induced reward or reinforcement mainly by inhibiting morphine-induced up-regulation of dopaminergic neuron activity in the ventral tegmental area and decreasing dopamine release in the nucleus accumbens with a fiber photometry recording system. These findings suggest that D₃R might play a very important role in opioid addiction, and YQA14 may have pharmacotherapeutic potential in attenuating opioid-induced addictive behaviors dependent on the dopamine system.
Rats ; Mice ; Animals ; Analgesics, Opioid ; Dopamine ; Heroin/pharmacology* ; Dopamine Antagonists/pharmacology* ; Receptors, Dopamine D3/metabolism* ; Morphine/pharmacology* ; Behavior, Addictive/drug therapy* ; Self Administration

BACKGROUND: Patients commonly develop postoperative pain after total knee arthroplasty (TKA). Acupuncture-related techniques and low-level laser therapy could be beneficial for pain management for older individuals. OBJECTIVE: To examine the effect of low-level laser acupuncture (LA) in reducing postoperative pain, pain-related interference in daily life, morphine consumption, and morphine-related side effects in older patients with knee osteoarthritis who underwent TKA. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: A single-blind randomized placebo-controlled trial was conducted. Patients (N = 82) were recruited and randomly assigned via a computer-generated list to the LA group or a placebo group. The LA group received low-level laser therapy at Sanyinjiao (SP6), Taixi (KI3), Kunlun (BL60), Fengshi (GB31), Futu (ST32) and Neiguan (PC6) after TKA, while the placebo acupuncture group received the same treatment procedure without laser energy output. MAIN OUTCOME MEASURES: The primary outcome was postoperative pain intensity, and it was measured at baseline and hours 2, 6, 10, 24, 48 and 72 after TKA. The secondary outcomes, including relative pain, postoperative pain-related interference in daily life and morphine consumption, were measured at hours 24, 48 and 72 after TKA. RESULTS: Generalized estimating equations revealed significant between-group differences in pain intensity (P = 0.01), and trend differences in pain intensity for the LA group starting at hours 10 to 72 (P < 0.05) and morphine consumption at hours 48 and 72 (P < 0.05). The changes in pain-related interference in daily life were significant (P < 0.05) at 72 h, with the exception of the parameters for worst pain, mood, and sleep. Nausea and vomiting side effects from morphine had significant between-group differences at hours 10 and 24 (P < 0.05). CONCLUSION: Low-level LA gradually reduced older patients' postoperative pain intensity and morphine consumption within the first 72 h after their TKA for osteoarthritis. Low-level LA may have benefits as an adjuvant pain management technique for clinical care. TRIAL REGISTRATION ClinicalTrials.gov registration number NCT03995446.
Acupuncture Therapy ; Aged ; Analgesics, Opioid/therapeutic use* ; Arthroplasty, Replacement, Knee/adverse effects* ; Double-Blind Method ; Humans ; Morphine/therapeutic use* ; Pain, Postoperative/drug therapy* ; Single-Blind Method

Background Ultrasound-guided continuous thoracic paravertebral block can provide pain-relieving and opioid-sparing effects in patients receiving open hepatectomy. We hypothesize that these effects may improve the quality of recovery (QoR) after open hepatectomy. Methods Seventy-six patients undergoing open hepatectomy were randomized to receive a continuous thoracic paravertebral block with ropivacaine (CTPVB group) or normal saline (control group). All patients received patient-controlled intravenous analgesia with morphine postoperatively for 48 hours. The primary outcome was the global Chinese 15-item Quality of Recovery score on postoperative day 7, which was statistically analyzed using Student's t-test. Results Thirty-six patients in the CTPVB group and 37 in the control group completed the study. Compared to the control group, the CTPVB group had significantly increased global Chinese 15-item Quality of Recovery scores (133.14 ± 12.97 vs. 122.62 ± 14.89, P = 0.002) on postoperative day 7. Postoperative pain scores and cumulative morphine consumption were significantly lower for up to 8 and 48 hours (P < 0.05; P = 0.002), respectively, in the CTPVB group. Conclusion Perioperative CTPVB markably promotes patient's QoR after open hepatectomy with a profound analgesic effect in the early postoperative period.
Anesthetics, Local/therapeutic use* ; Double-Blind Method ; Hepatectomy/adverse effects* ; Humans ; Morphine/therapeutic use* ; Pain Measurement ; Pain, Postoperative/etiology* ; Ultrasonography, Interventional

The periaqueductal gray (PAG) is a complex mesencephalic structure involved in the integration and execution of active and passive self-protective behaviors against imminent threats, such as immobility or flight from a predator. PAG activity is also associated with the integration of responses against physical discomfort (e.g., anxiety, fear, pain, and disgust) which occurs prior an imminent attack, but also during withdrawal from drugs such as morphine and cocaine. The PAG sends and receives projections to and from other well-documented nuclei linked to the phenomenon of drug addiction including: (i) the ventral tegmental area; (ii) extended amygdala; (iii) medial prefrontal cortex; (iv) pontine nucleus; (v) bed nucleus of the stria terminalis; and (vi) hypothalamus. Preclinical models have suggested that the PAG contributes to the modulation of anxiety, fear, and nociception (all of which may produce physical discomfort) linked with chronic exposure to drugs of abuse. Withdrawal produced by the major pharmacological classes of drugs of abuse is mediated through actions that include participation of the PAG. In support of this, there is evidence of functional, pharmacological, molecular. And/or genetic alterations in the PAG during the impulsive/compulsive intake or withdrawal from a drug. Due to its small size, it is difficult to assess the anatomical participation of the PAG when using classical neuroimaging techniques, so its physiopathology in drug addiction has been underestimated and poorly documented. In this theoretical review, we discuss the involvement of the PAG in drug addiction mainly via its role as an integrator of responses to the physical discomfort associated with drug withdrawal.
Amygdala ; Humans ; Morphine ; Nociception ; Periaqueductal Gray ; Substance-Related Disorders

OBJECTIVE: To observe the effect of early intervention of bone-nearby acupuncture (BNA) combined with electroacupuncture (EA) on the expression of histone deacetylase1(HDAC1), histone deacetylase 2 (HDAC2) andμ-opioid recepter (MOR) in dorsal root ganglia (DRG) of bone cancer pain-morphine tolerance (BCP-MT) rats, and to explore its possible mechanism. METHODS: A total of 35 SD rats were randomized into a sham BCP group (=6), a BCP group (=7), a MT group (=7), a BNA+EA group (=8) and a shame BNA group (=7). Except of the sham BCP group, cancer cell inoculation operation at left tibia was given in the other 4 groups to establish the bone cancer pain model. In the MT group, the BNA+EA group and the shame BNA group, intraperitoneal injection of morphine hydrochloride was given to establish the morphine tolerance model. After the operation, bone-nearby acupuncture combined with electroacupuncture was applied at "Zusanli" (ST 36) and "Kunlun" (BL 60) in the BNA+EA group, with dilatational wave, 2 Hz/100 Hz in frequency, 0.5 to 1.5 mA in intensity. Intervention in the shame BNA group was applied at the same time and acupoints as those in the BNA+EA group, the needles were pierced the skin without any electrical stimulation. The needles were retained for 30 min, once a day for continuous 7 days in both BNA+EA and shame BNA groups. Before and 10, 11, 15, 22 days after the operation, the left paw withdrawal threshold (PWT) was measured in the 5 groups. The levels of HDAC1, HDAC2 and MOR in DRG were detected by Western blot. RESULTS: Ten days after the cancer cell inoculation operation, the PWT of the BCP, MT, BNA+EA and sham BNA groups was decreased compared with the sham BCP group (<0.01). Eleven days after the operation, the PWT of the MT, BNA+EA and sham BNA groups was increased compared with the BCP group (<0.01). Twenty-two days after the operation, the difference was no significant between the BCP group and MT group (>0.05); the PWT of the BNA+EA group was increased compared with the MT and sham BNA group (<0.01). In the BCP group, the DRG levels of HDAC1 and HDCA2 were increased, while the level of MOR was decreased compared with the sham BCP group (<0.05, <0.01). In the MT group, the DRG level of HDAC1 was increased compared with the BCP group (<0.05). In the BNA+EA group, the DRG level of HDAC1 was decreased compared with the MT group and the sham BNA group (<0.01, <0.05), while the level of MOR was increased (<0.01). CONCLUSION Early intervention of bone-nearby acupuncture combined with electroacupuncture can relieve the morphine tolerance in bone cancer pain rats, it may relate to down-regulating the expression of HDAC1 and up-regulating the expression of MOR in the dorsal root ganglia.
Acupuncture Points ; Animals ; Bone Neoplasms ; complications ; Cancer Pain ; therapy ; Drug Tolerance ; Electroacupuncture ; Ganglia, Spinal ; metabolism ; Histone Deacetylases ; metabolism ; Morphine ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Opioid, mu ; metabolism

Preclinical studies suggest that the GABA receptor is a potential target for treatment of substance use disorders. Baclofen (BLF), a prototypical GABA receptor agonist, is the only specific GABA receptor agonist available for application in clinical addiction treatment. The nucleus accumbens shell (AcbSh) is a key node in the circuit that controls reward-directed behavior. However, the relationship between GABA receptors in the AcbSh and memory reconsolidation was unclear. The aim of this study was to investigate the effect of intra-AcbSh injection of BLF on the reconsolidation of morphine reward memory. Male C57BL/6J mice were used to establish morphine conditioned place preference (CPP) model and carry out morphine reward memory retrieval and activation experiment. The effects of intra-AcbSh injection of BLF on morphine-induced CPP, reinstatement of CPP and locomotor activity were observed after environmental cues activating morphine reward memory. The results showed that intra-AcbSh injection of BLF (0.06 nmol/0.2 μL/side or 0.12 nmol/0.2 μL/side), rather than vehicle or BLF (0.01 nmol/0.2 μL/side), following morphine reward memory retrieval abolished morphine-induced CPP by disrupting its reconsolidation in mice. Moreover, this effect persisted for more than 14 days, which was not reversed by a morphine priming injection. Furthermore, intra-AcbSh injection of BLF without morphine reward memory retrieval had no effect on morphine-associated reward memory. Interestingly, administration of BLF into the AcbSh had no effect on the locomotor activity of mice during testing phase. Based on these results, we concluded that intra-AcbSh injection of BLF following morphine reward memory could erase morphine-induced CPP by disrupting its reconsolidation. Activating GABA receptor in AcbSh during drug memory reconsolidation may be a potential approach to prevent drug relapse.
Animals ; Baclofen ; administration & dosage ; Conditioning, Classical ; GABA-B Receptor Agonists ; administration & dosage ; Locomotion ; Male ; Memory ; Mice ; Mice, Inbred C57BL ; Morphine ; Nucleus Accumbens ; drug effects ; Opioid-Related Disorders ; Reward

INTRODUCTION: Intrathecal morphine, commonly administered at doses of 100 to 200 mcg, is a popular choice for post-cesarean analgesia; however, a trade-off between opioid analgesia and side effects exists. This study was conducted to determine the lowest dose of intrathecal morphine that will provide adequate analgesia with the least side effects among post-cesarean patients. METHODS: Sixty term parturients for cesarean delivery under spinal anesthesia were randomized into three treatment groups to receive 50, 100 or 150 mcg of intrathecal morphine with a standard multimodal pain regimen and intravenous tramadol as needed. Pain scores, demand for rescue analgesic, and incidence of adverse effects (nausea, vomiting, and pruritus) during the first 24 hours’ post-spinal anesthesia were recorded and compared between groups. RESULTS: Pain scores and demand for rescue doses of tramadol were higher for the 50-mcg group as compared to the other groups. There was no significant difference in pain scores between the 100 and 150-mcg groups. No rescue dose of tramadol was necessary in the 100 and 150-mcg groups. No significant difference was seen in the incidence and severity of nausea and vomiting across treatment groups. The incidence and severity of pruritus were significantly higher in the 150-mcg group. No significant difference was noted in the incidence and severity of pruritus between the 50 and 100-mcg groups. CONCLUSION A dose of 100 mcg of intrathecal morphine, in combination with a multimodal regimen, provides adequate analgesia with the least side effects.
pain management ; Pregnancy ; Female ; Cesarean Section ; Anesthesiology ; Analgesics, Opioid ; morphine

Microglia are important cells involved in the regulation of neuropathic pain (NPP) and morphine tolerance. Information on their plasticity and polarity has been elucidated after determining their physiological structure, but there is still much to learn about the role of this type of cell in NPP and morphine tolerance. Microglia mediate multiple functions in health and disease by controlling damage in the central nervous system (CNS) and endogenous immune responses to disease. Microglial activation can result in altered opioid system activity, and NPP is characterized by resistance to morphine. Here we investigate the regulatory mechanisms of microglia and review the potential of microglial inhibitors for modulating NPP and morphine tolerance. Targeted inhibition of glial activation is a clinically promising approach to the treatment of NPP and the prevention of morphine tolerance. Finally, we suggest directions for future research on microglial inhibitors.
Humans ; Calcitonin Gene-Related Peptide/antagonists & inhibitors* ; Drug Tolerance ; Hypoglycemic Agents/pharmacology* ; Microglia/physiology* ; MicroRNAs/physiology* ; Minocycline/pharmacology* ; Morphine/pharmacology* ; Neuralgia/etiology* ; Plant Extracts/pharmacology* ; Signal Transduction/physiology*