Antinociceptive activity of coniine in mice.
BACKGROUND
Hemlock was used as an analgesic in certain ethnopharmacological traditions and there has been no record about the antinociceptive effect of coniine which is the major alkaloid compound of Hemlock.


OBJECTIVE
The present study was undertaken to evaluate the possible antinociceptive activity of coniine.


METHODS
Antinociceptive activity of coniine was tested dose in Hotplate test (thermal pain model) and in Writhing test (chemical pain model) in different nociception models.


RESULTS
Coniine caused a prolongation in reaction time in Hotplate test at 20mg/kg dose. In addition, it was observed that coniine decreased the number of writhes in Writhing test. Both data indicated an antinociceptive effect of coniine. A rotarod test was also conducted in order to clarify, whether this activity was related with a loss of locomotion or with an analgesic activity. None of the chemical agents at those doses used in experiments caused a loss of locomotor activity. It was also shown that antinociceptive effect of morphine was potentialized by coniine which was inhibited by nicotinic receptor blocker mecamylamine (1mg/kg).


CONCLUSIONS
Coniine has antinociceptive effect via the nicotinic receptors. A pharmacological assessment about the painless death of Socrates due to Hemlock (coniine) toxicity has also been presented by using this data.
Arihan
Okan
O
Department of Pharmacology, Faculty of Medicine, Hacettepe University, Ankara 06100, Turkey.
Boz
Mustafa
M
Iskit
Alper B
AB
Ilhan
Mustafa
M
D019342:Acetic Acid; D000470:Alkaloids / Q000494:pharmacology / Q000627:therapeutic use* / Q000633:toxicity; D000700:Analgesics / Q000494:pharmacology / Q000627:therapeutic use* / Q000633:toxicity; D000818:Animals; D029982:Conium / Q000737:chemistry*; D004357:Drug Synergism; D008297:Male; D008464:Mecamylamine / Q000494:pharmacology / Q000627:therapeutic use; D051379:Mice; D009020:Morphine / Q000494:pharmacology / Q000627:therapeutic use; D018733:Nicotinic Antagonists / Q000494:pharmacology / Q000627:therapeutic use; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D010880:Piperidines / Q000494:pharmacology / Q000627:therapeutic use* / Q000633:toxicity; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use* / Q000633:toxicity
D000470:Alkaloids; D000700:Analgesics; D018733:Nicotinic Antagonists; D010880:Piperidines; D010936:Plant Extracts; D008464:Mecamylamine; D009020:Morphine; C007112:coniine; D019342:Acetic Acid