title: Distribution and Morphology of Calcium-Binding Proteins Immunoreactive Neurons following Chronic Tungsten Multielectrode Implants.
abstract: The development of therapeutic approaches to improve the life quality of people suffering from different types of body paralysis is a current major medical challenge. Brain-machine interface (BMI) can potentially help reestablishing lost sensory and motor functions, allowing patients to use their own brain activity to restore sensorimotor control of paralyzed body parts. Chronic implants of multielectrodes, employed to record neural activity directly from the brain parenchyma, constitute the fundamental component of a BMI. However, before this technique may be effectively available to human clinical trials, it is essential to characterize its long-term impact on the nervous tissue in animal models. In the present study we evaluated how chronic implanted tungsten microelectrode arrays impact the distribution and morphology of interneurons reactive to calcium-binding proteins calbindin (CB), calretinin (CR) and parvalbumin (PV) across the rat's motor cortex. Our results revealed that chronic microelectrode arrays were well tolerated by the nervous tissue, with recordings remaining viable for up to 6 months after implantation. Furthermore, neither the morphology nor the distribution of inhibitory neurons were broadly impacted. Moreover, restricted microglial activation was observed on the implanted sites. On the whole, our results confirm and expand the notion that tungsten multielectrodes can be deemed as a feasible candidate to future human BMI studies.
authors.affiliation: Edmond and Lily Safra International Institute of Neurosciences (ELS-IIN), Santos Dumont Institute, Macaiba, RN, Brazil.
authors.forename: Marco Aurelio M
authors.initials: MA
authors.lastname: Freire
authors.affiliation: Laboratory of Neuroengineering, Department of Science and Technology, Federal University of São Paulo (UNIFESP), Sao Jose dos Campos, SP, Brazil.
authors.forename: Jean
authors.initials: J
authors.lastname: Faber
authors.affiliation: Edmond and Lily Safra International Institute of Neurosciences (ELS-IIN), Santos Dumont Institute, Macaiba, RN, Brazil.
authors.forename: Nelson Alessandretti M
authors.initials: NA
authors.lastname: Lemos
authors.affiliation: Laboratory of Neuroscience, Department of Biosciences, Federal University of Sergipe (UFS), Itabaiana, SE, Brazil.
authors.forename: Jose Ronaldo
authors.initials: JR
authors.lastname: Santos
authors.affiliation: Edmond and Lily Safra International Institute of Neurosciences (ELS-IIN), Santos Dumont Institute, Macaiba, RN, Brazil.
authors.forename: Pedro França
authors.initials: PF
authors.lastname: Cavalcanti
authors.affiliation: Memory Studies Laboratory, Department of Physiology, Federal University of Rio Grande do Norte (UFRN), Natal, RN, Brazil.
authors.forename: Ramon Hypolito
authors.initials: RH
authors.lastname: Lima
authors.affiliation: Edmond and Lily Safra International Institute of Neurosciences (ELS-IIN), Santos Dumont Institute, Macaiba, RN, Brazil; Associação Alberto Santos Dumont para Apoio a Pesquisa, Sirio-Libanes Hospital, São Paulo, SP, Brazil.
authors.forename: Edgard
authors.initials: E
authors.lastname: Morya
mesh_terms: D000818:Animals; D058256:Brain Waves / Q000502:physiology; D062207:Brain-Computer Interfaces / Q000009:adverse effects; D064092:Calbindin 1 / Q000378:metabolism*; D064032:Calbindin 2 / Q000378:metabolism*; D004567:Electrodes, Implanted / Q000009:adverse effects*; D020007:Implants, Experimental / Q000009:adverse effects*; D008297:Male; D017628:Microglia / Q000378:metabolism; D009044:Motor Cortex / Q000502:physiology / Q000601:surgery; D010320:Parvalbumins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D064092:Calbindin 1; D064032:Calbindin 2; D010320:Parvalbumins