The effects of capsaicin, bradykinin, PGE2 and cicaprost on the discharge of articular sensory receptors in vitro.
The responses of articular sensory receptors to capsaicin, bradykinin, PGE2, and the selective IP-receptor agonist cicaprost were studied in a rat isolated hindlimb in vitro preparation. Long-term maintenance of normal sensory receptor function was achieved in vitro under conditions of combined superfusion and slow perfusion. Response characteristics to mechanical or chemical stimuli on articular sensory receptors identified in this study did not differ to those reported in vivo. This preparation lacks complex effects mediated via spinal or central reflex mechanisms and allows greater control over the physiological environment of the receptors being studied. These results support the conclusion that the effects of capsaicin, bradykinin and the prostanoids are mediated by distinct pharmacological receptors associated with articular sensory nerve endings. The potent potentiating effects of cicaprost on bradykinin-induced excitation suggests that these actions are mediated via IP-receptors.
Department of Pharmacology, University of Edinburgh Medical School, UK.
G J
GJ
Birrell
D S
DS
McQueen
D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D002211:Capsaicin / Q000494:pharmacology*; D015232:Dinoprostone / Q000494:pharmacology*; D011464:Epoprostenol / Q000031:analogs & derivatives* / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008465:Mechanoreceptors / Q000187:drug effects; D009474:Neurons / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D011984:Sensory Receptor Cells / Q000187:drug effects*; D013643:Tarsus, Animal / Q000187:drug effects* / Q000294:innervation
D011464:Epoprostenol; D015232:Dinoprostone; C043867:cicaprost; D002211:Capsaicin; D001920:Bradykinin