Studies on the mechanism of the sedational state; "tranquilization" evoked by bradykinin or kallikrein in rats.
The mechanism of the sedative state "tranquilization" evoked by bradykinin(BK) or kallikrein(Kal), was studied. The drugs were injected intracerebroventricularly(icv) into the lateral ventricle, according to Yaksh's procedure. The behavior of a rat was estimated comparatively by the spontaneous movement. Two groups of animals were examined; one group was pretreated with prostaglandin (PG)-synthesis inhibitors, and the other group was not pretreated. The tranquilization was observed at the period of 12 to 16 min after BK or Kal injection. Almost of the PG-synthesis inhibitors reduced the tranquilization. On the contrary, eugenol or guaiacol, elongated the tranquilization. The levels of monoamines and PGs in the rat brain at the tranquilization, 15 min after BK injection detected with HPLC (high performance liquid chromatography). The levels of almost monoamines in the rat brain were decreased, however, PGE2 was increased considerably. Those results suggest that PGs is greatly involved in tranquilization evoked by BK or Kal.
Yazaki
K
K
Department of Pharmacology, Tokyo Dental College, Chiba, Japan.
D000818:Animals; D001920:Bradykinin / Q000008:administration & dosage / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism; D004837:Epinephrine / Q000378:metabolism; D007213:Indomethacin / Q000494:pharmacology; D007276:Injections, Intraventricular; D007610:Kallikreins / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D011453:Prostaglandins / Q000378:metabolism; D011458:Prostaglandins E / Q000008:administration & dosage / Q000494:pharmacology; D011796:Quinacrine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012701:Serotonin / Q000378:metabolism; D014149:Tranquilizing Agents
D011453:Prostaglandins; D011458:Prostaglandins E; D014149:Tranquilizing Agents; D012701:Serotonin; D007610:Kallikreins; D011796:Quinacrine; D001920:Bradykinin; D004298:Dopamine; D007213:Indomethacin; D004837:Epinephrine