Possible Interaction: Carrageenan and Serotonin

“Intraplantar formalin and carrageenan increased 5-HT (137+/-11% and 212+/-6% of pre-injection baseline, respectively) and reduced nociceptive threshold (23+/-7% and 19+/-3% of pre-injection baseline, respectively).”

“Extracellular concentrations of 5-HT and 5-HIAA in spinal dorsal horn and PAG significantly increased following carrageenan inflammation.”

“These results … of 5-HT in spinal … increases with carrageenan inflammation; the carrageenan-induced release of 5-HT and 5-HIAA in spinal cord may be tonically modulated by supraspinal … GABA systems, whereas the release in PAG may only be tonically modulated by endogenous GABA system in supraspinal level.”

“They have marked suppressive effect on … fresh egg protein, carrageenin, histamine and 5-HT , on the mouse's ear oedema induced by bimethylphenyl, on the exudate and proliferation of granulation tissue … and on the contents of PGE in the exudate of the swelling hind paw induced by injecting carrageenin.”

“Nevertheless, a slight reduction in the blood concentration of serotonin after pedal injection of carrageenin might indicate a local release of the amine.”

“Experi- ments using carrageenan have been credited with the dis- covery of indometacin (a cyclo-oxygenase inhibitor) and the identification of histamine, 5-hyclroxytryptamine ( 5-HT ), the kinins, and the PGs as active elements in inflammation.”