neuropeptide-y and Pain--Intractable

Electroconvulsive shock therapy (ECT) has been widely used as an effective and established treatment for refractory depression and schizophrenia. Some reports have shown that ECT is also effective for treating refractory neuropathic pain.. In a rat model of neuropathic pain produced by chronic constrictive injury (CCI) of the sciatic nerve, thermal hyperalgesia, and mechanical allodynia were observed from day 2 after surgery. An electroconvulsive shock (ECS) was administered to rodents once daily for 6 days on days 7-12 after CCI operation using a pulse generator. Thermal and mechanical stimulation tests were performed to assess pain thresholds. Real-time polymerase chain reaction was used to measure the gene expression levels for 5HT(1A)R, 5HT(2A)R, neuropeptide Y (NPY), and GABAA(alpha1)R in the brain.. After ECS, the latency to withdrawal from thermal stimulation was significantly increased; however, pain withdrawal thresholds in response to mechanical stimulation were not significantly changed. Expression ratios of NPY were significantly greater after ECS.. Symptoms of neuropathic pain improved and expression of NPY in the brain was increased in CCI model rats after ECS, suggesting that changes in the expression of NPY in the brain may be related to the mechanism of action of ECT in treating neuropathic pain.

Topics: Animals; Brain; Brain Chemistry; Disease Models, Animal; Electroconvulsive Therapy; gamma-Aminobutyric Acid; Gene Expression Regulation; Male; Neuropeptide Y; Pain Measurement; Pain Threshold; Pain, Intractable; Peripheral Nervous System Diseases; Rats; Rats, Sprague-Dawley; Reaction Time; Receptor, Serotonin, 5-HT1A; Receptor, Serotonin, 5-HT2A; Receptors, GABA-A; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sciatic Neuropathy; Serotonin; Synaptic Transmission; Up-Regulation

A novel method of cardiac denervation by cryoablation has been developed experimentally. The technique uses liquid nitrogen delivered under pressure to ablate the principal sources of cardiac innervation--namely, the adventitia surrounding the aorta, pulmonary arteries, and veins. The technique has been verified experimentally both in vivo by physiological means and in vitro by quantitative immunohistochemistry and the measurement of myocardial noradrenaline concentrations. A 35 year old woman presented with intractable precordial pain, normal epicardial coronary arteries, and hypertrophic cardiomyopathy. Her symptoms were refractory to maximal medical treatment and she was thought to be unsuitable for either conventional myocardial revascularisation, autotransplantation, or allografting with the concomitant risk of transplant coronary artery disease. She therefore underwent cardiac denervation by the method developed in the laboratory. There was quantitative immunohistochemical evidence of extrinsic cardiac denervation associated with a considerable improvement in her symptoms. This improvement persisted during a follow up period of over 16 months.

Topics: Adult; Cardiomyopathy, Hypertrophic; Chest Pain; Cryosurgery; Denervation; Female; Heart; Humans; Immunohistochemistry; Myocardium; Neuropeptide Y; Pain, Intractable; Thiolester Hydrolases; Ubiquitin Thiolesterase