Inhibitory effects of ethaverine, a homologue of papaverine, on dopamine content in PC12 cells.
The inhibitory effects of ethaverine on dopamine content in PC12 cells were investigated. Ethaverine decreased dopamine content in a concentration-dependent manner in PC12 cells and showed 33.6% inhibition of dopamine content at a concentration of 1.0 microM for 24-48 h. The IC50 value of ethaverine was 1.4 microM. Dopamine content was lowered at 6h and reached a minimal level at 12h after exposure to ethaverine at 2.0 microM. The decreased dopamine level was maintained up to 48 h and then recovered to the control level at about 72 h. Tyrosine hydroxylase (TH) was inhibited at 6 h following treatment with ethaverine in PC12 cells and the activity was maintained at a reduced level up to 36 h (12-22% inhibition at 2.0 microM). These results indicate that ethaverine leads to a decrease in dopamine content by inhibition of TH activity.
Shin
J S
JS
College of Pharmacy, Chungbhuk National University, Cheongju, Republic of Korea.
Lee
J J
JJ
Kim
Y
Y
Lee
C K
CK
Yun
Y P
YP
Lee
M K
MK
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020746:Calcium Channels, L-Type / Q000187:drug effects; D004298:Dopamine / Q000096:biosynthesis / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016716:PC12 Cells; D010208:Papaverine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D051381:Rats; D014446:Tyrosine 3-Monooxygenase / Q000037:antagonists & inhibitors
D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D004791:Enzyme Inhibitors; C007639:ethaverine; D010208:Papaverine; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine