A few years ago Yavin Shaham and Marina Wolf asked me if we had ever tracked pain longitudinally in our addiction-like behavioral model in HS rats. I was shocked and even ashamed that we had not, so we did it ;-) then took a while to replicate data and publish. We followed pain for 3 weeks of abstinence after oxycodone IVSA. Rats with mild addiction-like behavior recovered in a few days, like saline controls. Rats with severe addiction-like behavior were still hurting at 3 weeks. Opioid-induced hyperalgesia/allodynia is likely a driving force for opioid seeking during the first 3 weeks, but only in SOME individuals, those with the most severe addiction-like behavior. Milder forms may not need that negative reinforcement process or other forms of negative reinforcement are at play (emotional, other type of pain) Thanks Yavin and Marina for the initials spark of curiosity, and big thanks to Lani Tieu and Sonja Plasil who lead these studies Full blog post: oliviergeorge.com/news/2026-… Paper: doi.org/10.1016/j.neuropharm… @PsychiatryUcsd @UCSanDiego @NIH

I'm thrilled to announce that our Preclinical Addiction Research Consortium just got upgraded to a brand new P50 NIDA Center of Excellence, and became the Polysubstance Addiction Research Center. Seven years in the making! drugaddictionresearch.org/ We're studying cocaine, oxycodone, and alcohol in the same individuals, from genes to brain to gut. Then we test whether changing the biology changes the behavior. So thankful for this amazing team: Christine Cheng, Francesca Telese, Lieselot Carrette, Ben McKenna, Cristina Llorente, Bernd Schnabl, Giordano de Guglielmo, Kathleen Fisch, Abraham Palmer, Nick Hollon, and Lisa Maturin and Paul Schweitzer, who keep it all running. I'm immensely thankful for the support of NIDA Enough celebrating. Back to work! today.ucsd.edu/story/uc-san-… @NIH @NIDAnews @UCSanDiego @PsychiatryUcsd

FGFR1 in central amygdala PKCδ+ neurons promote punished alcohol drinking (using AAV and small-molecule). This data replicates earlier work from the Barak lab in the dorsomedial striatum, using the same inhibitor, but that time was on regular drinking, so likely not a compulsive-like-specific effect but that's irrelevant IMO. independent convergence across labs is great. My caveat though is that I am always worried about chronic manipulation of growth factor systems but that's my own bias. Great work @Heilig_Lab doi.org/10.1038/s41467-026-7…