Controlled demonstration of metrazol kindling.

Convulsive responses elicited in rats by intraperitoneal injections of metrazol were intensified following a seriew of metrazol injections administered once every three days. However, neither handling alone nor placebo injections increased the susceptibility of control rats to metrazol-induced convulsive symptoms. Thus, although increases in the susceptibility to metrazol seizures following periodic placebo injections have been reported by others, such increases do not appear to be a critical factor in metrazol kindling.