Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz

Direkt zur Navigaton springen.
Direkt zum Inhalt springen.

Navigation/Suche

Gewählte Publikation:

Maggi, CA; Patacchini, R; Tramontana, M; Amann, R; Giuliani, S; Santicioli, P.
Similarities and differences in the action of resiniferatoxin and capsaicin on central and peripheral endings of primary sensory neurons.
Neuroscience. 1990; 37(2):531-539 Doi: 10.1016/0306-4522(90)90421-Y
Web of Science PubMed FullText FullText_MUG

Autor*innen der Med Uni Graz:
Altmetrics:
Dimensions Citations:
Plum Analytics:
Scite (citation analytics):
Abstract:: We have compared the ability of capsaicin and resiniferatoxin, a natural diterpene present in the latex of plants of the Euphorbia family to excite and desensitize capsaicin-sensitive primary afferents in a variety of models. Both capsaicin and resiniferatoxin inhibited the twitch contractions of the rat isolated vas deferens and prevented, in a concentration-related manner, the effect of a subsequent challenge with 1 microM capsaicin (desensitization). Resiniferatoxin was 1000-10,000 times more potent than capsaicin in both cases. The time course of action of resiniferatoxin was much slower than that of capsaicin, suggesting a slower penetration rate in the tissue. The action of resiniferatoxin was blocked by Ruthenium Red, a proposed antagonist at the cation channel coupled to the capsaicin receptor. Both capsaicin and resiniferatoxin produced a contraction of the rat isolated urinary bladder. Resiniferatoxin was about as potent as capsaicin in this assay although it was 500-1000 times more potent than capsaicin in desensitizing the primary afferents to a subsequent challenge with capsaicin itself. Resiniferatoxin did not affect motility in the isolated vasa deferentia or urinary bladder from capsaicin-pretreated rats. After topical application onto the rat urinary bladder both resiniferatoxin (10 nM) and capsaicin (10 microM) increased bladder capacity as assessed in a volume-evoked micturition reflex model in rats without affecting micturition contraction. Intrarterial injection of resiniferatoxin or capsaicin in the ear of anesthetized rabbits evoked a systemic depressor reflex due to activation of paravascular nociceptors, resiniferatoxin being about three times more potent than capsaicin.(ABSTRACT TRUNCATED AT 250 WORDS)
Find related publications in this database (using NLM MeSH Indexing): Anesthesia -; Animals -; Calcitonin Gene-Related Peptide - metabolism; Capsaicin - antagonists and inhibitors; Diterpenes - antagonists and inhibitors; Ear, External - innervation; Male - innervation; Muscle Contraction - drug effects; Nerve Endings - drug effects; Neurons, Afferent - drug effects; Peripheral Nerves - drug effects; Rabbits - drug effects; Rats - drug effects; Rats, Inbred Strains - drug effects; Reflex - drug effects; Ruthenium Red - pharmacology; Spinal Cord - cytology; Substance P - metabolism; Urinary Bladder - innervation; Urination - drug effects; Vas Deferens - innervation