Full-length transient receptor potential vanilloid 1 channels mediate calcium signals and possibly contribute to osmoreception in vasopressin neurones in the rat supraoptic nucleus

- Full-length TRPV1 and a new splice variant, TRPV1_SON were expressed in the rat SON.
- Immunoreactivity of the N-terminal portion of TRPV1 was colocalized with that of AVP.
- Mannitol-induced [Ca2+]i responses were observed in AVP but not in OT neurones.
- Mannitol-induced [Ca2+]i responses were blocked by the TRPV1 antagonist CPZ and BCTC.
- At 36 °C, the TRPV1 agonist capsaicin evoked [Ca2+]i and ionic current responses.