TRPV1 and diabetes mellitus: Sensitization of peripheral TRPV1, TRPA1, and TRPC channels in non-peptidergic fibers by hydrogen sulfide synthesized by the cystathionine β-synthase enzyme, leading to hyperalgesia and loss of peripheral nerve fibers in a rat model of diabetes mellitus, was further validated by local peripheral injections of capsazepine, HC-030031, and SKF-96365 blockers (Agarwal et al., 2020).