Antinociceptive Effects of Heterotopic Electroacupuncture in Formalin-Induced Pain

2006 ◽  
Vol 34 (04) ◽  
pp. 565-574 ◽  
Author(s):  
Jae Hyo Kim ◽  
Young Seob Gwak ◽  
Inhyung Lee ◽  
In Churl Sohn ◽  
Min Sun Kim ◽  
...  
Keyword(s):  
Inflammatory Pain ◽  
Spinal Dorsal Horn ◽  
Late Phase ◽  
Antinociceptive Effect ◽  
Formalin Injection ◽  
Spinal Dorsal ◽  
Antinociceptive Effects ◽  
C Fiber ◽  
The Right ◽  
Lumbar Spinal

This study examined the antinociceptive effect of electroacupuncture (EA) to heterotopic acupoints on formalin-induced pain in rats. EA (2 ms, 10 Hz, and 3 mA) was delivered to heterotopic acupoints HE7 and PE7, or non-acupoints at the right fore limb, for 30 min and was immediately followed by subcutaneous formalin injection into the left hind paw, respectively. The quantified pain score, electromyogram (EMG) response of the C-fiber reflex, and cFos immunoreactivity were assessed, respectively. EA to heterotopic acupoints significantly reduced both early- and late-phase pain-like behaviors and significantly decreased the EMG responses of the C-fiber reflex after formalin injection. By contrast, EA to non-acupoints had no significant effects on pain-like behavior or the EMG response. In addition, EA to heterotopic acupoints decreased cFos immunoreactivity in the lumbar spinal dorsal horn. Therefore, EA induced pre-emptive antinociception via the extra-segmental inhibition of the formalin-induced pain, suggesting that EA to heterotopic acupoints is a useful treatment for inflammatory pain.

BDNF induces late-phase LTP of C-fiber evoked field potentials in rat spinal dorsal horn

2008 ◽  
Vol 212 (2) ◽  
pp. 507-514 ◽  
Author(s):  
Li-Jun Zhou ◽  
Yi Zhong ◽  
Wen-Jie Ren ◽  
Yong-Yong Li ◽  
Tong Zhang ◽  
...  
Keyword(s):  
Dorsal Horn ◽  
Spinal Dorsal Horn ◽  
Late Phase ◽  
Field Potentials ◽  
Spinal Dorsal ◽  
Evoked Field Potentials ◽  
C Fiber

Role of Prostaglandin Receptor EP1in the Spinal Dorsal Horn in Carrageenan-induced Inflammatory Pain

2002 ◽  
Vol 97 (5) ◽  
pp. 1254-1262 ◽  
Author(s):  
Yoshito Nakayama ◽  
Keiichi Omote ◽  
Akiyoshi Namiki
Keyword(s):  
Dorsal Horn ◽  
Inflammatory Pain ◽  
Early Phase ◽  
Spinal Dorsal Horn ◽  
Late Phase ◽  
Mechanical Hyperalgesia ◽  
Ion Concentration ◽  
Ipsilateral Side ◽  
Spinal Dorsal ◽  
Pge2 Concentration

Background Prostaglandin E2 (PGE2) and the receptor for PGE2 (EP receptor) are key factors contributing to the generation of hyperalgesia caused by inflammation. The current study was designed to investigate the roles of PGE2 and EP1 receptors in the spinal cord in the development and maintenance of inflammatory pain, using behavioral, microdialysis, and intracellular calcium ion concentration ([Ca2+]i) assays. Methods Inflammation was induced by an injection of carrageenan into the plantar surface of the rat hind paw. The effects of inflammation were evaluated at the time points of 3 h (early phase) and 15 h (late phase) after carrageenan injection. In behavioral assays, withdrawal thresholds to mechanical stimuli were evaluated. The effect of an intrathecally administered selective EP1 antagonist, ONO-8711, on the carrageenan-induced hyperalgesia was examined. Using a spinal microdialysis method, PGE2 concentration in the spinal dorsal horn was measured. In [Ca2+]i assays, we measured [Ca2+]i in the spinal dorsal horn in transverse spinal slices and examined the effects of pretreatment with ONO-8711. Sensitivities of the changes in [Ca2+]i to PGE2 perfusion were also assessed. Results Mechanical hyperalgesia and paw edema were observed in both the early and late phases. The hyperalgesia was inhibited by intrathecal ONO-8711 in the late, but not early, phase. The concentration of PGE2 in the spinal dorsal horn increased in the late phase. The [Ca2+]i in the dorsal horn increased on the ipsilateral side to the inflammation in the late, but not early phase. This increase was suppressed by the pretreatment with ONO-8711. Magnitude of the increase in [Ca2+]i on the ipsilateral side in response to PGE2 perfusion was greater in the late phase than in the early phase. Conclusion The results suggested that activation of spinal EP1 receptors was crucial in the carrageenan-induced mechanical hyperalgesia in the late phase. It seems that some of the mechanisms underlying inflammation-induced plastic changes are mediated by time-dependent increase in PGE2 concentration, activation of EP1 receptors, and increase in [Ca2+]i in the spinal dorsal horn.

Activation of Spinal D1/D5 Receptors Induces Late-Phase LTP of C-Fiber–Evoked Field Potentials in Rat Spinal Dorsal Horn

2005 ◽  
Vol 94 (2) ◽  
pp. 961-967 ◽  
Author(s):  
Hong-Wei Yang ◽  
Li-Jun Zhou ◽  
Neng-Wei Hu ◽  
Wen-Jun Xin ◽  
Xian-Guo Liu
Keyword(s):  
Protein Synthesis ◽  
Dorsal Horn ◽  
Receptor Agonist ◽  
Spinal Dorsal Horn ◽  
Sch 23390 ◽  
Late Phase ◽  
Field Potentials ◽  
Spinal Dorsal ◽  
Evoked Field Potentials ◽  
C Fiber

Long-term potentiation (LTP) of C-fiber–evoked field potentials in spinal dorsal horn may be relevant to pathological pain. Our previous work has shown that the late phase of the spinal LTP is protein synthesis–dependent. Considerable evidence has accumulated that dopamine D1/D5 receptors are important for late-phase LTP in hippocampus. In this study, the role of D1/D5 receptors in LTP of C-fiber–evoked field potentials in spinal dorsal horn was evaluated in urethan-anesthetized Sprague-Dawley rats. We found the following. 1) Spinal application of SKF 38393, a D1/D5 receptor agonist, induced a slowly developed LTP of C-fiber–evoked field potentials, lasting for >10 h, and the effect was blocked by the D1/D5 antagonist SCH 23390, whereas a D2 receptor agonist (quinpirole) induced depression of C-fiber responses, lasting for 2 h. 2) The potentiation produced by D1/D5 receptor agonist occluded the late phase but not the early phase of the spinal LTP produced by tetanic stimulation. 3) SCH 23390 selectively depressed the late-phase LTP, when applied 40 min before tetanic stimulation. 4) The D1/D5 agonist-induced potentiation is blocked by the protein synthesis inhibitor anisomycin. 5) Activation of protein kinase A by spinal application of 8-Br-cAMP also induced spinal LTP, and the action occluded the potentiation induced by the D1/D5 receptor agonist. These results suggest that the spinal D1/D5 receptors participate in the protein synthesis–dependent late-phase LTP of C-fiber–evoked field potentials in spinal dorsal horn through the cAMP signaling pathway.

Protein Synthesis Inhibition Blocks the Late-Phase LTP of C-Fiber Evoked Field Potentials in Rat Spinal Dorsal Horn

2003 ◽  
Vol 89 (5) ◽  
pp. 2354-2359 ◽  
Author(s):  
Neng-Wei Hu ◽  
Hong-Mei Zhang ◽  
Xiao-Dong Hu ◽  
Ming-Tao Li ◽  
Tong Zhang ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Dorsal Horn ◽  
Spinal Dorsal Horn ◽  
Late Phase ◽  
Tetanic Stimulation ◽  
Field Potentials ◽  
Spinal Dorsal ◽  
Phase Maintenance ◽  
Evoked Field Potentials ◽  
C Fiber

Previous studies have demonstrated that in the hippocampus the maintenance of long-term potentiation (LTP) requires de novo protein synthesis. To investigate the role of protein synthesis in the maintenance of LTP of C-fiber evoked field potentials in spinal dorsal horn, which may be relevant to hyperalgesia, protein synthesis inhibitor (either cycloheximide or anisomycin) was applied locally to the recording segments of spinal cord in anesthetized rats, 30 min prior to tetanic stimulation to the sciatic nerve. We found that both cycloheximide and anisomycin selectively inhibited late-phase maintenance of the spinal LTP but affected neither LTP induction nor baseline responses of C-fiber evoked field potentials. In the presence of cycloheximide, LTP of C-fiber evoked field potentials was 281.5 ± 16.5% ( n = 6) of baseline 1 h after tetanic stimulation and the potentiation significantly decreased to 235.5 ± 18.5% at 145 min after tetanic stimulation ( P< 0.05). Afterward, LTP of C-fiber evoked field potentials decreased continuously and at 270 min after tetanic stimulation reached 130.8 ± 18.0%, which was no longer different from baseline ( P > 0.05). Spinal application of anisomycin at 30 min before tetanic stimulation yielded similar results ( n = 6). These results suggest that protein synthesis may be crucial for the late-phase maintenance of LTP of C-fiber evoked field potentials in spinal dorsal horn.

scholarly journals Analgesic Effect of Combined Therapy with the Japanese Herbal Medicine “Yokukansan” and Electroacupuncture in Rats with Acute Inflammatory Pain

Medicines ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 31
Author(s):  
Nachi Ebihara ◽  
Hideshi Ikemoto ◽  
Naoki Adachi ◽  
Takayuki Okumo ◽  
Taro Kimura ◽  
...  
Keyword(s):  
Herbal Medicine ◽  
Inflammatory Pain ◽  
Analgesic Effect ◽  
Combined Therapy ◽  
Late Phase ◽  
Control Group ◽  
Formalin Injection ◽  
Japanese Herbal Medicine ◽  
Japanese Traditional Medicine ◽  
The Right

Background: Japanese herbal medicine, called Kampo medicine, and acupuncture are mainly used in Japanese traditional medicine. In this experiment, the analgesic effect of Yokukansan (YKS) alone and a combination of YKS and electroacupuncture (EA) on inflammatory pain induced by formalin injection were examined. Methods: Animals were divided into four groups: a control group, formalin injection group (formalin), YKS-treated formalin group (YKS), and YKS- and EA-treated formalin group (YKS + EA). The duration of pain-related behaviors and extracellular signal-regulated protein kinase (ERK) activation in the spinal cord after formalin injection in the right hind paw were determined. Results: The duration of pain-related behaviors was dramatically prolonged in the late phase (10–60 min) in the formalin group. The YKS treatment tended to reduce (p = 0.08), whereas YKS + EA significantly suppressed the pain-related behaviors (p < 0.01). Immunohistochemical and Western blot analyses revealed that the number of phosphorylated ERK1/2 (pERK1/2)-positive cells and the pERK expression level, which were increased by formalin injection, were significantly inhibited by YKS (p < 0.05) and YKS + EA (p < 0.01). Conclusions: The YKS + EA combination therapy elicited an analgesic effect on formalin-induced acute inflammatory pain.

SNAP25/syntaxin4/VAMP2/Munc18-1 Complexes in Spinal Dorsal Horn Contributed to Inflammatory Pain

Neuroscience ◽  
2020 ◽  
Vol 429 ◽  
pp. 203-212 ◽  
Author(s):  
Xing-Lian Duan ◽  
Zhen Guo ◽  
Yong-Tao He ◽  
Yin-Xia Li ◽  
Yan-Ni Liu ◽  
...  
Keyword(s):  
Dorsal Horn ◽  
Inflammatory Pain ◽  
Spinal Dorsal Horn ◽  
Spinal Dorsal

scholarly journals Clinical, behavioral and antinociceptive effects of crotalphine in horses

2015 ◽  
Vol 46 (4) ◽  
pp. 694-699
Author(s):  
Erica Cristina Bueno do Prado Guirro ◽  
João Henrique Perotta ◽  
Márcio de Paula ◽  
Yara Cury ◽  
Carlos Augusto Araújo Valadão
Keyword(s):  
Inflammatory Pain ◽  
Antinociceptive Effect ◽  
Behavioral Changes ◽  
Behavioral Effects ◽  
Phase Iii ◽  
Intact Skin ◽  
Kappa Opioid ◽  
Antinociceptive Effects ◽  
Analgesic Peptide ◽  
Scapular Region

ABSTRACT: Crotalphine is a novel analgesic peptide that acts on kappa opioid and delta receptors, causing powerful analgesia in rats submitted to inflammatory, neuropathic or oncologic models of pain. This study evaluated clinical, behavioral and antinociceptive effects caused by crotalphine in horses, employing 18 Arabian horses and it was divided in three phases. In Phase I, "clinical and behavioral effects", crotalphine did not change the latency to urinate and defecate; did not modify the values of cardiac or respiratory rates, intestinal motility and rectal temperature; and did not cause significant ataxia, head, eye and lip ptosis. In Phase II, "antinociceptive effect on intact skin at scapular or ischial region", crotalphine did not cause significant analgesia. In Phase III, "antinociceptive effect on incised skin at scapular or ischial region", crotalphine promoted effective antinociceptive effects for six hours and inhibited hyperalgesia state for three days in the ischial region of horses submitted to incisional model of inflammatory pain, but crotalphine did not evoke relevant analgesic effect on the scapular region. Concluding, intravenous injection of a single dose of crotalphine (3.8ngkg-1) did not cause important clinical or behavioral changes and promotes antinociceptive effect on incised ischial region for seven days in horses. Moreover, crotalphine did not evoke relevant anti nociceptive effect on the scapular region or in intact skin of horses.

Role of the NO-cGMP-K+ channels pathway in the peripheral antinociception induced by α-bisabolol

2021 ◽  
Author(s):  
Mario I Ortiz ◽  
Raquel Cariño-Cortés ◽  
Victor Manuel Muñoz Pérez ◽  
Andres Salas Casas ◽  
Gilberto Castañeda-Hernández
Keyword(s):  
Opioid Receptors ◽  
Formalin Test ◽  
Antinociceptive Effect ◽  
Dorsal Surface ◽  
Cyclic Guanosine Monophosphate ◽  
Guanosine Monophosphate ◽  
K Channel ◽  
Formalin Injection ◽  
K Channels ◽  
The Right

The aim of this study was to examine if the peripheral antinociception of α-bisabolol involve the participation of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) synthesis followed by K+ channel opening in the formalin test. Wistar rats were injected in the dorsal surface of the right hind paw with formalin (1%). Rats received a subcutaneous injection into the dorsal surface of the paw of vehicles or increasing doses of α-bisabolol (100-300 µg/paw). To determine whether the peripheral antinociception induced by α-bisabolol was mediated by either the opioid receptors or the NO-cGMP-K+ channels pathway, the effect of pretreatment (10 min before formalin injection) with the appropriate vehicles, naloxone, naltrexone, L-NAME, ODQ, glibenclamide, glipizide, apamin, charybdotoxin, tetraethylammonium or 4-aminopyridine on the antinociceptive effects induced by local peripheral α-bisabolol (300 µg/paw) were assessed. α-bisabolol produced antinociception during both phases of the formalin test. α-bisabolol antinociception was blocked by L-NAME, ODQ, and all the K+ channels blockers. The peripheral antinociceptive effect produced by α-bisabolol was not blocked by the opioid receptor inhibitors. α-bisabolol was able to active the NO-cGMP-K+ channels pathway in order to produce its antinoceptive effect. The participation of opioid receptors in the peripheral local antinociception induced by α-bisabolol is excluded.

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