Isolamento social na fase juvenil altera a plasticidade normal do córtex somatossensorial em ratas adolescentes

Gustavo Henrique Pereira; Letícia Alexandrino Barilli; Silvana Regina de Melo

doi:10.17765/2176-9206.2026v19e13520

Authors

Gustavo Henrique Pereira Universidade Estadual de Maringá https://orcid.org/0000-0002-1832-1430
Letícia Alexandrino Barilli Universidade Estadual de Maringá https://orcid.org/0000-0001-6536-8664
Silvana Regina de Melo Universidade Estadual de Maringá https://orcid.org/0000-0003-0968-4376

DOI:

https://doi.org/10.17765/2176-9206.2026v19e13520

Keywords:

Stress, Cortical thickness, Dendritic spines, Cerebral cortex

Abstract

Childhood social isolation results from a lack of contact with peers, and socialization is important in the normal development of social species such as humans and rodents. The aim of this study was to evaluate the effects of social isolation stress in the juvenile phase on the somatosensory cortex, a region related to the perception of tactile stimuli. The cortical thickness and density of dendritic spines in the Upper Lip, Barrel Cortex and Secondary Somatosensory subregions were analyzed. Twenty-seven Wistar rats (Rattus novergicus) were used, organized into Control and Social Isolation Stress groups. Social isolation took place between 21 and 35 days of postnatal life (P21-P35) and euthanasia was carried out at P43. The Nissl and Golgi-Cox histotechniques were used for histological analysis. The results showed neuroanatomical alterations in the group submitted to isolation, where Upper Lip showed less cortical thickness, associated with a lower density of spines. Barrel Cortex showed greater thickness, which may depend on neuronal factors that were not investigated.

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Author Biographies

Gustavo Henrique Pereira, Universidade Estadual de Maringá

He is studying for a master's degree in Pharmaceutical Sciences at the State University of Maringá and has a degree in Biological Sciences from the same university. He is currently a member of the Neurodevelopment/Stress/Neuroplasticity research group, whose main line of research is assessing the effects of childhood stress on brain morphology under the guidance of Professor Dr. Silvana Regina de Melo. He has already carried out two research projects under the Institutional Program for Scientific Initiation Scholarships (PIBIC), funded by the Araucária Foundation, with research relating stress in childhood and its short-term and adult effects. Also works as a volunteer neuroscience teacher for elementary school students preparing for the Brazilian Neuroscience Olympiad. Was also a fellow of the Pedagogical Residency Program of the Biology Subproject during 2023 and 2024.

Letícia Alexandrino Barilli, Universidade Estadual de Maringá

Master's degree from the Pharmaceutical Sciences Program (UEM) (Concept 5 Capes), she completed an internship funded by NAPI Neurosciences at the Federal University of Paraná, with the main line of research being the evaluation of the effects of stress on brain morphology. Graduated in Biomedicine from the State University of Maringá (UEM) 2018-2022. During her undergraduate studies, she worked in extension as a member of the board of UEM's Academic League of Embryology and Human Genetics (LAEGH) and in the PET-Health/Interprofessional Program funded by the Ministry of Health (2019-2021). In research, she received a grant from the Araucária Foundation Program for research relating stress in childhood and its results in adults, evaluating neuroplasticity and neurodevelopment of the fornix, at the Morphological Sciences Laboratory.

Silvana Regina de Melo, Universidade Estadual de Maringá

She has a degree in Biological Sciences from the State University of Maringá (1990), a master's degree in Biological Sciences/ Human Anatomy from Universidade Estadual Paulista Júlio de Mesquita Filho/ UNESP/Botucatu (1996) and Ph. Biological Sciences from the University of São Paulo/ USP (2000), Post-doctorate in Neurosciences from the University of Lethbridge, Canada (2015), and Philipps Universitat Marburg/ Germany (2020). He has been teaching at the State University of Maringá since 1991, mainly in the subjects of Neuroanatomy and Neurosciences in undergraduate and postgraduate courses, such as Psychiatry Residency, and in the Postgraduate Program in Pharmaceutical Sciences. Her line of research and extension work focuses on Neurodevelopment and Brain Neuroplasticity in Stress.

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