231 | Towards a comprehension of dopaminergic modulation of pain: physiological, morphological and neurochemical characterization of dopamine-sensitive neurons of the Anterior Insular Cortex.

Neural excitability, synaptic transmission and neuron-glia interactions

Author: María Jesús Trujillo | Email: jesutruji@gmail.com

María Jesús Trujillo , Jesica Unger , Analía López Díaz , Fernando Kasanetz

1° Universidad de Buenos Aires – CONICET. Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay), Facultad de Medicina, Departamento de Ciencias Fisiológicas. Grupo Neurociencia en Sistemas. Buenos Aires, Argentina.

Pain is a sensory and emotional experience that arises from distributed brain activity. The anterior insular cortex (AIC) is a key brain region for pain perception, integrating sensory, emotional, motivational, and cognitive functions. The mesolimbic dopaminergic system, known for responding to motivational events, modulates pain perception and is disrupted in pathological pain conditions. Dopamine release in the AIC affects nociception, particularly inducing pain relief through D1 receptors (D1R). Despite this, it is not clear how dopamine controls AIC microcircuits activity.
In order to characterize the dopaminergic system of the AIC in mice, we first identified dopamine-sensitive neurons within the AIC. Our findings revealed that D1R-bearing neurons located in the superficial layers of the AIC are primarily inhibitory interneurons, while D1R-positive cells in deeper layers comprise both pyramidal cells and interneurons. Through a combination of immunohistochemistry, electrophysiology, and morphological reconstructions, we thoroughly characterized the interneurons expressing D1R in the AIC. Furthermore, we assessed the impact of D1R agonists on the excitability of these neurons.
Together, this data will aid in comprehending how dopamine influences information integration in AIC microcircuits. In the near future we will address the role of AIC dopamine-sensitive neurons on pain related behaviors using neuronal calcium imaging in vivo and chemogenetic manipulations.