M. Bennay et al., Spontaneous remission of paroxysmal dystonia coincides with normalization of entopeduncular activity in dt(sz) mutants, J NEUROSC, 21(13), 2001, pp. NIL_6-NIL_9
Recent studies have shown a dramatically decreased spontaneous discharge ra
te of entopeduncular neurons in a unique animal model of idiopathic paroxys
mal dystonia, the dt(sz) mutant hamster. These changes were found in animal
s at the age at which the most marked expression of dystonia is usually obs
erved. In this rodent model, the age-dependent disappearance of stress-indu
cible dystonic attacks at an age of similar to 10 weeks allows investigatio
ns of the relevance of pathophysiological changes for the occurrence of dys
tonia by ontogenetic studies. Therefore, we examined the entopeduncular act
ivity by extracellular single unit recordings in groups of dt(sz) mutants a
nd nondystonic control hamsters at 17-22 weeks of age. In contrast to recen
t findings, after the complete remission of dystonia, the mean discharge ra
te of entopeduncular neurons in dt(sz) mutants (28.1 +/- 1.2 spikes/sec) wa
s similar to that of age-matched nondystonic control hamsters (30.8 +/- 0.9
spikes/sec). Thus, the disappearance of paroxysmal dystonia is accompanied
by a normalization of the entopeduncular activity in dt(sz) mutants. The p
resent data clearly demonstrate the fundamental importance of a decreased b
asal ganglia output for the expression of paroxysmal dystonia.