Effects of organotin compounds on maximal electroshock seizure (MES) responsiveness in mice. I. TRI(n-alkyl)tin compounds.

Male mice (25-30 g) were injected (ip) with 0, 3.5 X 10(-6), or 17.5 X 10(-6) mol trimethyltin bromide (TMT), triethyltin bromide (TET), tri-n-propyltin chloride (TPT), or tri-n-butyltin bromide (TBT) per kg. Additional groups of mice were also injected (ip) with either 0 or 17.5 X 10(-6) mol sodium bromide (NaBr) or 17.5 X 10(-6) mol stannic bromide (SnBr4) per kg. The mice were tested with maximal electroshock seizure (MES) at 0.5, 4, 21-24, and 96 h following exposure to the organotin compounds. Mice exposed to TMT, TET, TPT, or TBT exhibited dose-dependent decreases in MES severity as evaluated by seizure-grade distributions and duration of tonic seizure phases. The tri-n-alkyltin compounds exhibited a structure-activity relationship in their ability to decreased maximal responsiveness to the MES test. In order of decreasing ability they were: TMT greater than TET greater than TPT greater than TBT. Administration of NaBr and SnBr4 did not alter MES responsiveness, indicating the essential role of the alkyl moieties of the tri-n-alkyltin compounds in producing alterations in central nervous system function.