Laminar-selective spinal astrocyte population capable of converting tactile information into nociceptive in rats

We previously identified a spinal astrocyte population that expresses hairy and enhancer of split 5 (Hes5) and is selectively present in superficial laminae in mice. However, it was unclear whether such astrocyte heterogeneity is commonly observed across species. Using adeno-associated viral (AAV) vectors incorporating a rat Hes5 promotor (AAV-Hes5P), we found that AAV-Hes5P-captured astrocytes were selectively located in the superficial laminae in rats. Furthermore, activation of AAV-Hes5P⁺ astrocytes elicited allodynia-like behavior and increased c-FOS⁺ cells in the superficial laminae. Thus, laminar-selective Hes5⁺ astrocytes are conserved beyond species and have the capability to convert tactile information to nociceptive.