TRPC4/TRPC5 are critical for neuronal modulation by transcranial focused ultrasound in retrosplenial cortex in male mice

Transcranial focused ultrasound (tFUS) enables non-invasive neuromodulation, yet its underlying molecular mechanisms remain largely elusive. Here, we show that transient receptor potential canonical 4 (TRPC4) and transient receptor potential canonical 5 (TRPC5) channels are critical mediators of tFUS-induced neuronal modulation in the mouse brain. Applying tFUS to the retrosplenial cortex (RSC) in male mice desensitizes mechanical and thermal sensitivity while robustly elicits early growth response 1 (Egr1) expression. Inhibiting these tFUS-induced Egr1 ensembles blocks the somatic sensory effects. Transcriptomic analysis identifies Trpc4 enrichment in tFUS-activated Egr1-positive cells. Both pharmacological inhibition and genetic knockdown of TRPC4 abolish tFUS-mediated sensory modulation. Targeted knockdown further demonstrates that the highly homologous TRPC5 plays a comparable role. In situ proximity ligation assay, co-immunoprecipitation, and live-cell calcium imaging confirm that TRPC4 and TRPC5 form a protein complex in the RSC that facilitates the tFUS response. These findings establish TRPC4/TRPC5 as essential molecular components for tFUS neuromodulation.