Plasticity of cortico-striatal neurons of the anterior cingulate cortex during experimental neuropathic pain

MARÍA JESÚS TRUJILLO; CONSTANZA ILARRAZ; FERNANDO KASANETZ

NEUROSCIENCE

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2023 vol. 523 p. 91 - 104

0306-4522

Maladaptive neuronal plasticity is a main mechanism for the development and maintenance of pathological pain. Affective, motivational and cognitive deficits that are comorbid with pain involve cellular and synaptic modifications in the anterior cingulate cortex (ACC), a major brain mediator of pain perception. Here we use a model of neuropathic pain (NP) in male mice and ex-vivo electrophysiology to investigate whether layer 5 ACC neurons projecting to the dorsomedial striatum (DMS), a critical region for motivational regulation of behavior, are involved in aberrant neuronal plasticity. We found that while the intrinsic excitability of cortico-striatal ACC neurons (ACC-CS) was preserved in NP animals, excitatory postsynaptic potentials (EPSP) induced after stimulation of distal inputs were enlarged. The highest synaptic responses were evident both after single stimuli and in each of the EPSP that compose responses to trains of stimuli, and were accompanied by increased synaptically-driven action potentials. EPSP temporal summation was intact in ACC-CS neurons from NP mice, suggesting that the plastic changes were not due to alterations in dendritic integration but rather through synaptic mechanisms. These results demonstrate for the first time that NP affects ACC neurons that project to the DMS and reinforce the notion that maladaptive plasticity of the cortico-striatal pathway may be a key factor in sustaining pathological pain.