Mutually opposite effects of dopamine.HCl and chlorpromazine. HCl on the thickness of liposomal lipid bilayers.
The aim of this study was to provide a basis for examining the molecular mechanism for the pharmacological action of dopamine.HCl (DA) and chlorpromazin.HCl (CPZ). Radiationless energy transfer from the surface fluorescent probe, 1-anilinonaphthalene-8-sulfonic acid, to the hydrophobic fluorescent probe, bispyrenylpropane (Py-Py), was used to examine the effects of DA and CPZ on the thickness (D) of the liposomal lipid bilayers prepared with total lipids (SPMVTL) and phospholipids (SPMVPL) extracted from neuronal membranes. The thickness (D) of intact SPMVTL and SPMVPL (37 degrees C, pH 7.4) were 0.914 +/- 0.010 and 0.886 +/- 0.009 (arbitrary units, n = 5), respectively. DA decreased the thickness of both SPMVTL and SPMVPL in a dose-dependent manner with a significant decrease in thickness observed even at 40 x 10(-9) M and 40 x 10(-9) M, respectively. On the other hand, CPZ increased the thickness of both SPMVTL and SPMVPL in a dose-dependent manner with a significant increase in thickness observed even at 35 x 10(-5) M and 35 x 10(-5) M, respectively. The sensitivities to the decreasing and increasing effect of the membrane lipid bilayers thickness by DA and CPZ, respectively, differed according to the liposomes in descending order of SPMVPL and SPMVTL. The decreasing and increasing action of DA and CPZ, respectively, on the membrane thickness had many effects that may be responsible for the dopaminergic receptor-DA and -CPZ interaction as well as the protein-lipid interaction.
Department of Dental Pharmacology and Biophysics, Pusan National University, Yangsan, Korea.
Tae-Sang
TS
Jung
Jeong-Kuk
JK
Kim
Ki Yong
KY
Nam
Kyung-Zoo
KZ
Lee
Sung-Key
SK
Lee
Wang Bong
WB
Park
Myung-Suk
MS
Ko
Won-Il
WI
Kim
Byung-Kug
BK
Kim
Byung Soo
BS
Kim
Young Chan
YC
Jeon
In Kyo
IK
Chung
Moon Kyoung
MK
Bae
Hye-Ock
HO
Jang
Il
I
Yun
D000817:Anilino Naphthalenesulfonates / Q000737:chemistry; D002746:Chlorpromazine / Q000494:pharmacology*; D004298:Dopamine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004735:Energy Transfer / Q000187:drug effects; D005456:Fluorescent Dyes / Q000737:chemistry; D066298:In Vitro Techniques; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000138:chemical synthesis / Q000648:ultrastructure*; D010743:Phospholipids / Q000737:chemistry; D011721:Pyrenes / Q000737:chemistry
D000817:Anilino Naphthalenesulfonates; D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D008055:Lipids; D008081:Liposomes; D010743:Phospholipids; D011721:Pyrenes; C027132:1-anilino-8-naphthalenesulfonate; D002746:Chlorpromazine; D004298:Dopamine