RELATIONSHIP BETWEEN PENTYLENETETRAZOL-INDUCED SEIZURES AND BRAIN PENTYLENETETRAZOL LEVELS IN MICE

  • 1 January 1980
    • journal article
    • research article
    • Vol. 214  (3) , 589-593
Abstract
Pentylenetetrazol (PTZ) is often used in experimental models of epilepsy. The relationship of the PTZ-induced seizure sequence of myoclonus, clonus and hindlimb extension (TE) to brain PTZ levels was not reported. This study examined this relationship and determined how different routes of PTZ administration affected brain PTZ uptake and seizure development. The critical brain PTZ level for onset of clonus ranged from 20-50 .mu.g/g. Brain PTZ uptake was rapid after i.p. injection of PTZ [convulsant dose (CD55) for clonus] and clonus onset occurred at 4.0 .+-. 1.6 min. Uptake was slower after s.c. administration; clonus onset occurred at 9.9 .+-. 3.7 min. At a CD for TE (CD40) , clonus onset occurred at 5.1 .+-. 3.0 and 2.4 .+-. 2.4 min for s.c. and i.p. routes of administration, respectively. TE onset did not appear to depend solely on brain PTZ levels since it sometimes occurred when brain PTZ levels were falling. Factors that could modulate the appearance of TE are discussed.