Comparative epileptogenic properties of two monobactam derivatives in C57, Swiss and DBA/2 mice.

The behavioural and electrocortical effects of two monobactam derivatives were studied after intraperitoneal (ip) administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures, and in C57 and Swiss mice, two strains not prone to seizure. DBA/2 mice were more susceptible than Swiss and C57 mice to seizures induced by aztreonam or carumonam. No significant differences were observed between seizures elicited by aztreonam and carumonam in animals (DBA/2 only) administered intracerebroventricularly or ip. Although the main mechanism for seizure-like activity of monobactams cannot be easily determined, we believe that several mechanisms may be involved. An increased excitation of the central nervous system (CNS) by inhibition of GABA binding to receptors and a slow clearance of aztreonam and carumonam from the CNS may be postulated.