RESUMEN
OBJECTIVE: Perception of touch is expected at the location where it is applied. However, there are indications that being touched may be perceived on the contralateral side when seen as a reflection in a mirror at midline. Such inter-lateral referral of sensation (RS) lacks evidence, as mirror therapy research usually focusses on movement-based techniques. This study aimed to map out existing research across disciplines regarding the effect of RS in health and disease, and to understand whether there is rehabilitation potential in RS. METHOD: A scoping review was conducted to map out concepts and keywords across disciplines interested in this topic, using keywords in several languages, and a wide range of databases and additional sources. RESULTS: The review revealed mostly cross-sectional experiments and included over 486 participants: healthy, or with stroke, complex regional pain syndrome, amputation, nerve graft surgery or radial fracture. Procedures varied regarding stimulation tool, time and location, with two stimulating replacements, one the face and one a variety of areas. Response rates ranged from 0 to 100%.In general, RS was regarded as a phenomenon or even as a predictor of maladaptive neuroplasticity. There was little research into using RS stimulation as a modulatory tool to improve sensory perception. CONCLUSIONS: RS challenges the understanding of touch perception and elicits a range of questions regarding neuro-processing. A modulatory approach using RS has not been described, requires investigation and, if promising, development as an intervention.
Asunto(s)
Ilusiones , Estudios Transversales , Humanos , Ilusiones/fisiología , Pruebas Neuropsicológicas , Derivación y Consulta , Tacto/fisiologíaRESUMEN
The compound SB-612111 [(-)-cis-1-methyl-7-[[4-(2,6-dichlorophenyl)piperidin-1-yl]methyl]-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ol] was recently identified as a selective antagonist for the nociceptin/orphanin FQ (N/OFQ) peptide receptor (NOP). In the present study, the in vitro pharmacological profile of SB-612111 at human recombinant NOP receptors expressed in Chinese hamster ovary (CHO) cells [receptor binding, guanosine 5'-O-(3-[(35)S]thio)triphosphate (GTPgamma[(35)S]) binding, and cAMP level experiments] as well as at native NOP receptors expressed in peripheral (mouse and rat vas deferens, guinea pig ileum) and central (mouse cerebral cortex synaptosomes releasing [(3)H]5-HT) preparations was evaluated and compared with that of the standard nonpeptide antagonist (+/-)J-113397 [(+/-)-trans-1-[1-cyclooctylmethyl-3-hydroxymethyl-4-piperidyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one]. SB-612111 produced a concentration-dependent displacement of [(3)H]N/OFQ binding to CHO(hNOP) cell membranes, showing higher affinity and NOP selectivity over classical opioid receptors than (+/-)J-113397. SB-612111 and (+/-)J-113397 competitively antagonized the effects of N/OFQ on GTPgamma[(35)S] binding in CHO(hNOP) cell membranes (pK(B), 9.70 and 8.71, respectively) and on cAMP accumulation in CHO(hNOP) cells (pK(B), 8.63 and 7.95, respectively), being per se inactive. In isolated peripheral tissues of mice, rats, and guinea pigs and in mouse cerebral cortex synaptosomes preloaded with [(3)H]5-HT, SB-612111 competitively antagonized the inhibitory effects of N/OFQ, with pA(2) values in the range of 8.20 to 8.50. In parallel experiments, (+/-)J-113397 was found to be 2- to 9-fold less potent than SB-612111. In the electrically stimulated tissues, 1 microM SB-612111 did not modify the effects of classical opioid receptor agonists. In conclusion, the results of the present study demonstrated that SB-612111 is among the most potent and NOP-selective nonpeptide antagonists identified to date.