Effect of Extremely Low Frequency Electromagnetic Field and/or GABAB Receptors on Foot Shock-induced Aggression in Rats

INTRODUCTION The present study investigated the interactive effect of GABAB receptors and extremely low frequency electromagnetic field (ELF-EMF) on foot shock-induced aggression in rats. METHODS Fifty adult male rats were randomly assigned into 10 groups. Groups 2, 4, 6, 8 and 10 were exposed to 50 Hz, 500 µT ELF-EMF for 30 days 8h per day while the remaining groups (1, 3, 5, 7 and 9) were sham-exposed. At the end of this period, the animals in groups 1 and 2 received normal saline while groups 3 and 4 treated with 100 mg/kg (low dose) of CGP35348 and groups 5 and 6 injected with 200 mg/kg (high dose) of CGP35348. Groups 7 and 8 treated with 1.7 mg/kg (low dose) of Baclofen and groups 9 and 10 received 3 mg/kg (high dose) Baclofen by IP injections. Twenty min after the injection, the aggressive behavior was recorded in foot shock-induced aggression model. The number of lateral threat, lifted up threat, biting, attacking, chasing and approaching were considered as paradigms of aggressive behavior. RESULTS ELF-EMF, Baclofen or CGP35348 alone had no significant effect on aggressive behavior. Except that rats exposed and treated with low dose of CGP35348 demonstrated significantly higher numbers of only one of the paradigms of aggressive behavior (lifted up threats), CGP35348 and Baclofen in both doses in combination with ELF-EMF exposure had no significant effect on aggression. DISCUSSION GABAB receptors and ELF-EMFs had no effect (both enhancement and suppression) on aggressive behavior of rats in foot shock-induced model of aggression.