title: Expression and distribution of TRPV2 in rat brain.
abstract: Transient receptor potential (TRP) proteins are non-selective cation channels that mediate sensory transduction. The neuroanatomical localization and the physiological roles of isoform TRPV2 in the rodent brain are largely unknown. We report here the neuroanatomical distribution of TRPV2 in the adult male rat brain focusing on the hypothalamus and hindbrain regions involved in osmoregulation, autonomic function and energy metabolism. For this we utilized immunohistochemistry combined with brightfield microscopy. In the forebrain, the densest immunostaining was seen in both the supraoptic nucleus (SON) and the magnocellular division of the paraventricular nucleus (PVN) of the hypothalamus. TRPV2 immunoreactivity was also seen in the organum vasculosum of the lamina terminalis, the median preoptic nucleus and the subfornical organ, in addition to the arcuate nucleus of the hypothalamus (ARH), the medial forebrain bundle, the cingulate cortex and the globus pallidus to name a few. In the hindbrain, intense staining was seen in the nucleus of the solitary tract, hypoglossal nucleus, nucleus ambiguous, and the rostral division of the ventrolateral medulla (RVLM) and some mild staining in the area prostrema. To ascertain the specificity of the TRPV2 antibody used in this paper, we compared the TRPV2 immunoreactivity of wildtype (WT) and knockout (KO) mouse brain tissue. Double immunostaining with arginine vasopressin (AVP) using confocal microscopy showed a high degree of colocalization of TRPV2 in the magnocellular SON and PVN. Using laser capture microdissection (LCM) we also show that AVP neurons in the SON contain TRPV2 mRNA. TRPV2 was also co-localized with dopamine beta hydroxylase (DBH) in the NTS and the RVLM of the hindbrain. Based on our results, TRPV2 may play an important role in several CNS networks that regulate body fluid homeostasis, autonomic function, and metabolism.
authors: Department of Integrative Physiology, University of North Texas Health Science Center at Fort Worth, 3500 Camp Bowie Blvd, Fort Worth, TX 76107, USA.
authors: Thekkethil Prashant
authors: TP
authors: Nedungadi
authors: Mayurika
authors: M
authors: Dutta
authors: Chandra Sekhar
authors: CS
authors: Bathina
authors: Michael J
authors: MJ
authors: Caterina
authors: J Thomas
authors: JT
authors: Cunningham
mesh_terms: D000818:Animals; D001341:Autonomic Nervous System / Q000378:metabolism / Q000502:physiology; D001826:Body Fluids / Q000378:metabolism / Q000502:physiology; D001923:Brain Chemistry / Q000235:genetics; D015220:Calcium Channels / Q000235:genetics / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology; D007031:Hypothalamus / Q000378:metabolism; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009415:Nerve Net / Q000378:metabolism / Q000502:physiology; D051381:Rats; D012249:Rhombencephalon / Q000378:metabolism; D013495:Supraoptic Nucleus / Q000737:chemistry / Q000378:metabolism; D050916:TRPV Cation Channels / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*
chemical_list: D015220:Calcium Channels; D050916:TRPV Cation Channels; C485717:Trpv2 protein, mouse; C476722:Trpv2 protein, rat