Neurological and behavioral toxicity of kryptopyrrole in the rat.

Ten rats were given 9.1 to 82 mg/kg of 2,4-dimethyl-3-ethylpyrrole (kryptopyrrole) and the behavioral and electroencephalographic effects were studied. Kryptopyrrole was found to decrease EEG voltage, disrupt synchronization and induce abnormal spiking at a variety of cortical sites. Intermittent periods of low frequency hypersynchronous EEG activity was consistently elicited by kryptopyrrole. These waves bear a resemblance to the hypersynchronous EEG patterns associated with hallucinatory agents such as LSD-25. Marked behavioral alterations were observed following the initial injection including ataxia, hyperventilation, locomotor depression and catelepsy. Kryptopyrrole causes major central nervous system dysfunction, and these findings are discussed in the context of a drug-induced model of psychoses.