| First Author | Bajic D | Year | 2018 |
| Journal | Neuroscience | Volume | 384 |
| Pages | 397-405 | PubMed ID | 29885522 |
| Mgi Jnum | J:264780 | Mgi Id | MGI:6196642 |
| Doi | 10.1016/j.neuroscience.2018.05.041 | Citation | Bajic D, et al. (2018) Cannabinoid Receptor Type 1 in the Brain Regulates the Affective Component of Visceral Pain in Mice. Neuroscience 384:397-405 |
| abstractText | Endocannabinoids acting through cannabinoid receptor type 1 (CB1) are major modulators of peripheral somatic and visceral nociception. Although only partially studied, some evidence suggests a particular role of CB1 within the brain in nociceptive processes. As the endocannabinoid system regulates affect and emotional behaviors, we hypothesized that cerebral CB1 influences affective processing of visceral pain-related behaviors in laboratory animals. To study nocifensive responses modulated by supraspinal CB1, we used conditional knock-out mice lacking CB1 either in cortical glutamatergic neurons (Glu-CB1-KO), or in forebrain GABAergic neurons (GABA-CB1-KO), or in principal neurons of the forebrain (CaMK-CB1-KO). These mutant mice and mice treated with the CB1 antagonist SR141716 were tested for different pain-related behaviors. In an acetic acid-induced abdominal constriction test, supraspinal CB1 deletions did not affect nocifensive responses. In the cerulein-model of acute pancreatitis, mechanical allodynia or hyperalgesia were not changed, but Glu-CB1- and CaMK-CB1-KO mice showed significantly increased facial grimacing scores indicating increased affective responses to this noxious visceral stimulus. Similarly, these brain-specific CB1 KO mice also showed significantly changed thermal nociception in a hot-plate test. These results reveal a novel, and important role of CB1 expressed by cortical glutamatergic neurons in the affective component of visceral nociception. |
