Articles: neuropathic-pain.
-
We have recently demonstrated that sciatic nerve injury increases the expression of spinal cytochrome P450c17, a key neurosteroidogenic enzyme, which plays a critical role in the development of peripheral neuropathic pain. However, the modulatory mechanisms responsible for the expression of spinal P450c17 have yet to be examined. Here we investigated the possible involvement of interleukin-1β (IL-1β) in altering P450c17 expression during the induction phase of neuropathic pain. ⋯ Intrathecal administration of IL-1ra (20 ng) on days 0 to 3 post-surgery also facilitated the CCI-induced development of mechanical allodynia, and this early developed pain was dose-dependently attenuated by the administration of the P450c17 inhibitor, ketoconazole (1, 3, or 10 nmol) or the astrocyte metabolic inhibitor, fluorocitrate (0.01, 0.03, or 0.1 nmol). These results demonstrate that early increases in spinal IL-1β temporally inhibit astrocyte P450c17 expression and astrocyte activation ultimately controlling the development of mechanical allodynia induced by peripheral nerve injury. These findings imply that spinal IL-1β plays an important role as an early, but transient, control mechanism in the development of peripheral neuropathic pain via the inhibition of astrocyte P450c17 expression and astrocyte activation.
-
Stereotact Funct Neurosurg · Jan 2019
Case ReportsGamma Knife Radiosurgery for Trigeminal Neuralgia Reduces Neurovascular Compression: A Case Report after 11 Years.
Trigeminal neuralgia (TN) is a rare and debilitating craniofacial pain syndrome often caused by vascular compression of the trigeminal nerve. Gamma Knife radiosurgery (GKRS) has been shown to offer a less invasive yet effective treatment method for pain reduction in TN. In this case report, we observed radiological evidence of resolved neurovascular compression after 11 years for a patient with recur-rent TN and prior GKRS. ⋯ In this case, we demonstrate that vessel-nerve relationships may change over time in TN patients treated with GKRS, which raises the possibility that GKRS could ease a neurovascular compression.
-
Transl Perioper Pain Med · Jan 2019
BIX01294, a G9a inhibitor, alleviates nerve injury-induced pain hypersensitivities during both development and maintenance periods.
Genetic knockdown or knockout of the histone methytransferase G9a in the injured dorsal root ganglion (DRG) has been shown to alleviate neuropathic pain development. However, the application of genetic strategy in clinic is highly limited. The present study sought to examine the effect of intrathecal BIX01294, a specific G9a inhibitor, on the development and maintenance of pain hypersensitivities caused by unilateral L5 spinal nerve injury (SNL) or chronic constriction injury (CCI) to the sciatic nerve in rats. ⋯ These effects were dose-dependent. Intrathecal administration of BIX01294 also blocked the SNL-induced increase in the level of H3K9me2, a marker of G9a activity, and reversed SNL-induced downregulation of Oprm1 mRNA, Oprk1 mRNA, Oprd1 mRNA, Kcna2 mRNA, and Kcna4 mRNA, the downstream targets of G9a, in the ipsilateral L5 DRG. These findings further implicate that G9a as a potential target in the management of neuropathic pain.
-
We have demonstrated that electroacupuncture (EA) of "Weizhong" (BL 40) and "Huantiao" (GB 30) could evidently relieve mechanical hyperalgesia in spared nerve injury (SNI) rats. The present study was designed to observe the effect of EA on levels of cAMP, and protein kinase A (PKA) and cAMP response element binding protein (CREB) in the lumbar spinal cord of the same pain model rats, so as to explore its mechanisms underlying improvement of neuropathic pain. ⋯ EA intervention-induced down-regulation of cAMP, PKA and CREB levels in the lumbar spinal cord may contribute to its analgesic effect in neuropathic pain rats, suggesting an involvement of reduction of cAMP/PKA/CREB signaling of spinal cord in EA analgesia.
-
Case Reports
[Postherpetic neuralgia of the left trigeminus nerve V1 : Successful therapy with capsaicin 8% patch].
A 68-year-old patient suffered from postzoster neuralgia with severe pain of the left trigeminal nerve V1. Despite medication with gabapentin 1800 mg/d, oxacarbazepine 600 mg, tapentadol 500 mg/d, amitriptyline 20 mg as well as ambroxol 20% ointment and lidocaine patch topically, the pain reached an intensity of 8-10 on the numeric rating scale (NRS). Wearing a CPAP (continuous positive airway pressure) mask at night to treat a sleep apnea was impossible or the mask was leaking under lidocaine patch, only topical ambroxol 20% brought a certain pain relief. ⋯ Six weeks after application, the average pain during the day was only NRS 3/10 despite a considerable reduction in oral medication. Three months after the second treatment, the patient was almost pain-free during the day. Topical capsaicin 8% patch is, in our opinion, also safe and successful to use on the face with appropriate experience of the user.