The effect of 3,4-diaminopyridine on the patients with hereditary pure cerebellar ataxia.
BACKGROUND
Downbeat nystagmus (DBN) is often seen in patients with pure cerebellar type of spinocerebellar ataxia (SCA) like spinocerebellar ataxia type 6 (SCA6). DBN frequently presents with other cerebellar symptoms such as postural imbalance or ataxia. A potassium channel blocker 3,4-diaminopyridine (3,4-DAP) has been reported to reduce DBN by increasing the excitability of Purkinje cells.


OBJECTIVE
The objective of this study is to determine whether 3,4-DAP has a beneficial effect on DBN along with postural imbalance and ataxic symptoms in 10 patients with SCA6 and five patients with chromosome 16q22.1-linked autosomal dominant cerebellar ataxia (16q-ADCA).


RESULTS
The patients took 20mg of 3,4-DAP twice a day for a week. DBN was observed in seven patients with SCA6 and two with 16q-ADCA. Although 3,4-DAP significantly reduced DBN (P<0.05), other ataxic symptoms did not improved. However, 3,4-DAP showed benefit in two patients with oscillopsia.


CONCLUSIONS
3,4-DAP may be effective on DBN and oscillopsia, although it was not proved to be effective on other symptoms of ataxia in SCA patients.
Tsunemi
Taiji
T
Department of Neurology and Neurological Science, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. ttsunemi@ucsd.edu
Ishikawa
Kinya
K
Tsukui
Kei
K
Sumi
Takuro
T
Kitamura
Ken
K
Mizusawa
Hidehiro
H
D015761:4-Aminopyridine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000077770:Amifampridine; D001259:Ataxia / Q000150:complications / Q000188:drug therapy / Q000235:genetics; D004334:Drug Administration Schedule; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D020417:Nystagmus, Congenital / Q000150:complications / Q000188:drug therapy* / Q000235:genetics; D011187:Posture; D026902:Potassium Channel Blockers / Q000627:therapeutic use; D020754:Spinocerebellar Ataxias / Q000150:complications / Q000188:drug therapy* / Q000235:genetics; D016896:Treatment Outcome
D026902:Potassium Channel Blockers; D015761:4-Aminopyridine; D000077770:Amifampridine