NeurochemistryExistence of capsaicin-sensitive glutamatergic terminals in rat hypothalamusSasamura, Takashi1; Sasaki, Miwa1; Tohda, Chihiro2; Kuraishi, Yasushi1,3Author Information 1Department of Applied Pharmacology, Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930–0194, Japan 2Analytical Research Center for Ethnomedicines, Research Institute for Wakan-yaku, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930–0194, Japan. 3Corresponding Author: Yasushi Kuraishi Website publication 10 June 1998 Received 24 March 1998; accepted 15 April 1998 NeuroReport: June 22, 1998 - Volume 9 - Issue 9 - p 2045-2048 Buy Abstract CAPSAICIN has been suggested to act not only on thin primary afferents but also on the hypothalamus, but the neurotransmitter(s) of central capsaicin-sensitive neurons are unknown. The present study was conducted to determine whether any central, especially hypothalamic, glutamatergic terminals were sensitive to capsaicin. Capsaicin evoked glutamate release from slices of hypothalamus and lumbar dorsal horn, but not cerebellum. Such capsaicin action was Ca2+ dependent and inhibited by the capsaicin antagonist capsazepine. Vanilloid receptor subtype 1 mRNA was widely distributed in the brain, with a marked level in the hypothalamus and cerebellum, but not in the spinal cord. The results suggest that there are glutamatergic terminals sensitive to capsaicin in the hypothalamus. © Lippincott-Raven Publishers.