Nicotine tolerance to PC12 cell line: acute and chronic exposures modulate dopamine D2 receptor and tyrosine hydroxylase expression.
PC12 is a clonal cell line from chromaffin tumor of rat adrenal pheochromocytoma that releases catecholamine including dopamine, which via interaction with its receptor (D(1) and D(2) receptor), is known to be involved in reward and reinforcement properties of many addictive drugs like nicotine. Nicotine tolerance is the key aspect of nicotine addiction. However, nicotine tolerance on dopamine receptors in PC12 cell line is poorly understood. In this paper, we have demonstrated the tolerance to acute and chronic nicotine administrations on PC12 cell line on the basis of the expressions of dopamine receptors and tyrosine hydroxylase, the rate-limiting enzyme of dopamine biosynthesis, by Western blot, immunohistochemistry and in situ hybridization. In vitro treatment of nicotine resulted in similar expressional changes of dopamine D(2) receptor and tyrosine hydroxylase at protein and mRNA levels in dose- and time-dependent manner, whereas dopamine D(1) receptor did not reveal any positive output. Moreover, moderate to strong signals were obtained from 0.1 to 10 microM of nicotine concentrations and the signals were gradually decreased at 100 and 1000 microM nicotine concentrations relative to the untreated control cell line. Therefore, this study implied a new approach towards nicotine tolerance which is likely to be related to the modulation of dopamine D(2) receptor and tyrosine hydroxylase expressions by chronic and acute nicotine exposures in PC12 cell line.
Naha
Nibedita
N
Division of Life Science, Applied Life Science (Brain Korea 21 and EB-NCRC), Gyeongsang National University, Jinju 660-701, South Korea.
Lee
Hae Young
HY
Hwang
Jin Su
JS
Bahk
Jong Yoon
JY
Park
Moon Seok
MS
Lee
Sang Yeol
SY
Kim
Sung Hoon
SH
Kim
Myeong Ok
MO
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D015870:Gene Expression / Q000187:drug effects; D009538:Nicotine / Q000008:administration & dosage*; D016716:PC12 Cells; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017447:Receptors, Dopamine D1 / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D013997:Time Factors; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
D012333:RNA, Messenger; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D009538:Nicotine; D014446:Tyrosine 3-Monooxygenase