Novel anticonvulsant action of chronic melatonin in gerbils.
Melatonin, a hormone from the pineal gland, was tested for its anticonvulsant effects in male gerbils. Daily administration of melatonin (25 micrograms injection-1, s.c.) for ten weeks reduced the number and severity of seizures (total convulsion score: 7.67 +/- 1.83 in controls vs 2.47 +/- 0.90 in melatonin-injected animals, p < 0.05) associated with the injection of the convulsant, pentylenetetrazol (PTZ, 60 mg kg-1, s.c.). However, neither 12 weeks of short photoperiod exposure (LD 10:14) nor biweekly administration of melatonin pellets altered PTZ-induced convulsions. Overall, melatonin-injected gerbils were better able to survive and respond to seizures than control animals. No melatonin-injected gerbils died during seizure induction (0/31) while 5 out of 33 control gerbils died after PTZ injection. The mechanism for melatonin's anticonvulsant effects could be due to a direct inhibitory action on neural activity or a conversion of melatonin to an anticonvulsant compound that resembles the kynurenines.
Champney
T H
TH
Department of Human Anatomy and Medical Neurobiology, College of Medicine, Texas A&M University Health Science Center, College Station 77843-1114.
Champney
J A
JA
D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D005849:Gerbillinae; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D009929:Organ Size / Q000187:drug effects; D010433:Pentylenetetrazole; D017440:Photoperiod; D012640:Seizures / Q000139:chemically induced / Q000517:prevention & control; D013737:Testis / Q000187:drug effects
D000927:Anticonvulsants; D008550:Melatonin; D010433:Pentylenetetrazole