Electrophysiological effects of triiodothyronine and propranolol.

The effects of triiodothyronine (T3), T3 combined with propranolol, and propranolol alone on somatosensory evoked responses (SER) and EEG were studied in 2 groups each of 6 male volunteer subjects. The following results were obtained: (1) T3 increased SER amplitude during the first 100 ms after stimulus. (2) Addition of propranolol eliminated the SER amplitude increase resulting from T3 administration. (3) Neither T3 nor T3 plus propranolol significantly altered the mean level or the temporal variability of EEG amplitude and frequency. (4) There were no significant effects of propranolol alone on SER and EEG measures.