Inhibition of GABAergic neurons in the paraventricular nucleus of the hypothalamus precipitates visceral pain induced by pancreatic cancer in mice

Background: For patients with pancreatic cancer, visceral pain is a debilitating symptom that significantly compromises their quality of life. Unfortunately, the lack of effective treatment options can be attributed to our limited understanding of the neural circuitry underlying this phenomenon. The primary objective of this study is to elucidate the fundamental mechanisms governing visceral pain induced by pancreatic cancer in murine models. Methods: electrophysiological patch-clamp technique was utilized to record the electrophysiological activity of GABAergic neurons. Specific neuron ablation and chemogenetics methods were employed to investigate the involvement of GABAergic neurons in pancreatic cancer-induced visceral pain. Results: electrophysiological results showed that the firing frequency of GABAergic neurons in the paraventricular nucleus of the hypothalamus (PVN) was decreased. Specific destruction of GABAergic neurons in the PVN exacerbated visceral pain induced by pancreatic cancer. Chemogenetics activation of GABAergic neurons in the PVN alleviated visceral pain induced by pancreatic cancer. Conclusions: GABAergic neurons located in PVN play a crucial role in precipitating visceral pain induced by pancreatic cancer in mice, thereby offering novel insights for identifying effective targets to treat pancreatic cancer-related visceral pain.