Clinical trial. The effects of
protirelin tartrate (TRH-T) administration on chronic post-
stroke spasticity were studied in a multicentre trial (study on the treatment of chronic post-
stroke spasticity--11 centres involved). Patient evaluation included the quantification of muscular strength examined in proximal and distal areas, muscular tone according to the Ashworth scale, reflex intensities (using a 5 graded scale); daily autonomy was also considered according to the Parkside Behaviour Rating Scale (PBRS). Patients were administered 2 mg of TRH-T twice daily by intramuscular route. The most interesting finding emerging from the trial was that TRH-T administration elicited, at the same time, a reduction of spasticity, hypertonia and
hyperreflexia together with an increase in muscular strength and improvement of daily activities. The therapeutic profile of TRH-T therefore seems to be based on its unusual capacity of acting simultaneously on deficiency symptoms (hyposthenia, loss of dexterity) and positive symptoms (hypertonia,
hyperreflexia), both of which are present in cases of post-
stroke spasticity. Electrophysiological findings. By means of coded electrophysiological tests it is possible to explore specific compartments of the motorial and spinal network and consequently obtain activity profiles for each single substance capable of modifying its reactivity. The H/M ratio, reciprocal Ia inhibition and the activities of the Renshaw circuit were not changed following TRH-T administration. Opposite findings were recorded with regard to the F wave according to whether the
flector or extensor nucleus was explored; the consequent hypothesis of TRH-T activity at the interneuron level was supported by the inhibition of the short head biceps reflex following administration of the
drug.(ABSTRACT TRUNCATED AT 250 WORDS)