Alpha melanocyte stimulating hormone (α-MSH) does not modify pentylenetetrazol- and pilocarpine-induced seizures.
OBJECTIVE
Alpha-melanocyte stimulating hormone (α-MSH) is a pro-opiomelanocortin (POMC)-derived peptide involved in different neurological functions that also exerts anti-inflammatory effects, including in the central nervous system (CNS). Although inflammation has been implicated in seizures and epilepsy, no study has systematically investigated whether α-MSH modifies seizures. Therefore, in the current study we determined whether α-MSH alters pentylenetetrazol (PTZ)- and pilocarpine-induced seizures.


METHODS
Adult male Swiss mice were injected with α-MSH (1.66, 5 or 15 μg/3 μL, intracerebroventricular (i.c.v.)) or systemic (0.1, 0.3 or 1 mg/kg, intraperitoneally (i.p.)). Five to sixty minutes after the injection of the peptide, animals were injected with PTZ (60 mg/kg, i.p.) or pilocarpine (370 mg/kg, i.p.). Latency to myoclonic jerks and tonic-clonic seizures, number of seizure episodes, total time spent seizing and seizure intensity, assessed by the Racine and Meurs scales were recorded. Interleukin 1 beta (IL-1β) levels in the hippocampus were measured by a commercial enzyme-linked immunoabsorbent assay (ELISA).


RESULTS
Neither intracerebroventricular (1.66, 5 or 15 μg/3 μL, i.c.v.) nor systemic (0.1, 0.3 or 1 mg/kg, i.p.) administration of α-MSH altered PTZ- and pilocarpine-induced seizures. IL-1β levels in the hippocampi were not altered by α-MSH, PTZ or pilocarpine.


CONCLUSIONS
Although inflammation has been implicated in seizures and epilepsy and α-MSH is a potent anti-inflammatory peptide, our results do not support a role for α-MSH in seizure control.
Graduate Program in Pharmacology, Center of Health Sciences, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil.
Fernanda Rossatto
FR
Temp
Aline Carré
AC
Santos
Joseane Righes
JR
Marafiga
Ana Cláudia
AC
Jesse
Quéli Fernandes
QF
Lenz
Sara Marquesan
SM
Oliveira
Gustavo Petri
GP
Guerra
Teresa Nieves
TN
Scimonelli
Carlos Fernando
CF
Mello
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000276:immunology; D053583:Interleukin-1beta / Q000032:analysis / Q000276:immunology; D008297:Male; D051379:Mice; D010433:Pentylenetetrazole; D010862:Pilocarpine; D012640:Seizures / Q000139:chemically induced* / Q000188:drug therapy*; D000521:alpha-MSH / Q000494:pharmacology*
D000893:Anti-Inflammatory Agents; D053583:Interleukin-1beta; D010862:Pilocarpine; D000521:alpha-MSH; D010433:Pentylenetetrazole
Central inflammation; Epilepsy; Melanocyte-stimulating-hormone