Banca de DEFESA: BEATRIZ MONFERRARI MARTINS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : BEATRIZ MONFERRARI MARTINS
DATE: 28/01/2026
TIME: 10:00
LOCAL: Plataforma TEAMS
TITLE:

CHEMOGENETIC MODULATION OF THE REWARD SYSTEM IN RATS SUBMITTED TO THE CONDITIONED PLACE PREFERENCE TEST

KEY WORDS:

Dependence, conditioning-place-preference, DREADDs, ketamine

PAGES: 100
BIG AREA: Ciências da Saúde
AREA: Medicina
SUMMARY:

“Substance Use Disorder (SUD) is a global health problem, characterized by recurrent and compulsive use despite adverse consequences. The neurobiology of SUD involves alterations in the reward system, known as the mesocorticolimbic system, particularly the dopaminergic pathway. Understanding the underlying mechanisms of this system, as well as the impact of intrinsically linked environmental reinforcement, is fundamental for the development of more effective therapies. In this scenario, chemogenetic tools, such as the Designer receptor Exclusively Activated by Designer Drugs (DREADD) technique, enable the temporary, reversible, and non-toxic neuromodulation of circuits in genetically defined cellular populations, which adds unprecedented precision to the study of these systems. The Conditioning Place Preference (CPP) test is a behavioral paradigm used to measure the hedonic of value of substances. The test quantifies the preference an animal develops by associating drug administration with environmental cues, which indicates motivation for seeking and associative learning, based on the time spent in the conditioned place. The objective of the present study was to evaluate the behavioral effects of chemogenetic modulation of the mesolimbic pathway in the CPP paradigm in Wistar rats. Two viral vectors were used, both carrying inhibitory receptors with tropism for neurons and interneurons, respectively, in the nucleus accumbens and ventral tegmental area. The animals were subjected to the CPP apparatus upon receptor activation by CNO 5 mg/Kg i.p., and the CPP test was also performed with the drug ketamine 10 mg/Kg i.p. the experimental design of the CPP was separated into habituation, conditioning, and test phases, with minor variations between groups according to the surgical procedures and literature data. Isolated modulation of the mesolimbic system, by both vectors, did not demonstrate relevant behavioral changes, nor did the control group for the activating drug CNO show preference. On the contrary, ketamine demonstrated preference when compared to the baseline data of the experimental subjects at specific time points. All analyses considered baseline data, as the animals showed innate preference for the one side of the apparatus. Histological analysis confirmed expression in the surgical targets, and statistical analyses were performed using the GraphPad Prism software. The results demonstrate that the chemogenetic modulation performed is not sufficient to activate the reward system, and thus, this methodology can be associated with tests involving drugs of abuse, in order to identify the possibility of modulating previously activated system. The preference generated by ketamine 10 mg/Kg was not uniform, requiring further testing to establish its standardization. The findings provide a basis for research that mimics the neuronal state of SUD patients, with the aim of developing more precise pharmacological therapeutic targets for treatment.”

COMMITTEE MEMBERS:
Externa à Instituição - LILIAN DOS ANJOS CARNEIRO - UNIEURO
Externa ao Programa - 1302038 - LUANA CRISTINA CAMARGO - nullExterno ao Programa - 1744566 - MAURICIO HOMEM DE MELLO - nullPresidente - 1952915 - RAFAEL PLAKOUDI SOUTO MAIOR