title: Antinociceptive effect and mechanism of action of isatin, N-methyl isatin and oxopropyl isatin in mice.
abstract: OBJECTIVE
  There has been growing interest in the synthesis of new derivatives from isatin, found in Isatis genus. Our objectives were to characterize the antinociceptive mechanism of action of isatin, N-methyl-isatin (MI) and N-methyl-3-(2-oxopropyl)-3-hydroxy-2-oxindole (MOI).
  
  
  METHODS
  Substances (0.1-10mg/kg, p.o.) were studied in chemical (paw licking induced by formalin, capsaicin or glutamate) or thermal (hot plate) models of nociception. The involvement of several systems was evaluated using different receptor antagonists.
  
  
  RESULTS
  All three substances inhibit both phases of formalin-induced licking, increase the area under the curve and MI and MOI have a higher effect than that of morphine (in hot plate). Capsaicin and glutamate-induced licking were also reduced by all three substances. In the hot plate model, the antinociceptive effect of isatin was reduced by naloxone and atropine; naloxone, atropine and L-NAME reduced MI effect while naloxone, atropine, L-NAME, mecamylamine and ondansetron reduced MOI effect.
  
  
  CONCLUSIONS
  Our results suggest that isatin, MI and MOI: 1) present activity in models of nociception; 2) capsaicin and glutamate receptors seems to participate in the mechanism of action; 3) opioid, cholinergic, serotoninergic, nitrergic and adrenergic systems may be involved, at least in part, in the mechanism of action of some of these substances.
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas, Laboratório de Farmacologia da Dor e da Inflamação, Brasil.
authors.forename: Thais Biondino Sardella
authors.initials: TBS
authors.lastname: Giorno
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Química-CT, Bloco A. Rio de Janeiro, Brasil.
authors.forename: Bárbara Vasconcellos da
authors.initials: BVD
authors.lastname: Silva
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Química-CT, Bloco A. Rio de Janeiro, Brasil.
authors.forename: Angelo da Cunha
authors.initials: ADC
authors.lastname: Pinto
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas, Laboratório de Farmacologia da Dor e da Inflamação, Brasil. Electronic address: patricia.dias@icb.ufrj.br.
authors.forename: Patricia Dias
authors.initials: PD
authors.lastname: Fernandes
mesh_terms: D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007510:Isatin / Q000031:analogs & derivatives* / Q000494:pharmacology* / Q000627:therapeutic use; D008464:Mecamylamine / Q000494:pharmacology; D051379:Mice; D009020:Morphine / Q000494:pharmacology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009270:Naloxone / Q000494:pharmacology; D017294:Ondansetron / Q000494:pharmacology; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement / Q000187:drug effects
chemical_list: D000700:Analgesics; D009270:Naloxone; D017294:Ondansetron; D008464:Mecamylamine; D009020:Morphine; D001285:Atropine; D007510:Isatin; D019331:NG-Nitroarginine Methyl Ester
keywords: Analgesia; Antinociception; Isatin; Opioid; Pain