PMID- 8795126
OWN - NLM
STAT- MEDLINE
DCOM- 19961122
LR  - 20191101
IS  - 1059-1311 (Print)
IS  - 1059-1311 (Linking)
VI  - 5
IP  - 2
DP  - 1996 Jun
TI  - Mechanisms of T-type calcium channel blockade by zonisamide.
PG  - 115-9
AB  - We investigated the effects of zonisamide, a new antiepileptic drug, on 
      voltage-dependent T-type calcium current (ICa) in cultured neuroblastoma cells of 
      human origin (NB-I). Zonisamide reduced T-type ICa in a concentration-dependent 
      manner without evoking any change in its inactivation kinetics or voltage 
      dependence of action. The mean percent reduction was 38.3 +/- 5.8% at 50 microM. 
      Further, zonisamide shifted the inactivation curve approximately 20 mV negative 
      compared to the control. These resting blocking actions suggest that zonisamide 
      shifts the channel population toward the inactivation state, allowing fewer 
      channels to open during membrane depolarization. The blockade of T-type calcium 
      channels by zonisamide could suppress an important component of inward current 
      that underlies epileptiform cellular bursting, thereby inhibiting the spread of 
      seizure activity.
FAU - Kito, M
AU  - Kito M
AD  - Department of Pediatrics, Minami Seikyo Hospital, Nagoya, Japan.
FAU - Maehara, M
AU  - Maehara M
FAU - Watanabe, K
AU  - Watanabe K
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Seizure
JT  - Seizure
JID - 9306979
RN  - 0 (Anticonvulsants)
RN  - 0 (Calcium Channel Blockers)
RN  - 0 (Isoxazoles)
RN  - 459384H98V (Zonisamide)
SB  - IM
MH  - Anticonvulsants/*pharmacology
MH  - Calcium Channel Blockers/*metabolism
MH  - Cell Culture Techniques
MH  - Epilepsy/drug therapy
MH  - Humans
MH  - Isoxazoles/*pharmacology
MH  - Neuroblastoma/*drug therapy
MH  - Zonisamide
EDAT- 1996/06/01 00:00
MHDA- 1996/06/01 00:01
CRDT- 1996/06/01 00:00
PHST- 1996/06/01 00:00 [pubmed]
PHST- 1996/06/01 00:01 [medline]
PHST- 1996/06/01 00:00 [entrez]
AID - S1059-1311(96)80104-X [pii]
AID - 10.1016/s1059-1311(96)80104-x [doi]
PST - ppublish
SO  - Seizure. 1996 Jun;5(2):115-9. doi: 10.1016/s1059-1311(96)80104-x.