Inhibitory effects of caffeine on gustatory plasticity in the nematode Caenorhabditis elegans.
The effects of caffeine on salt chemotaxis learning were investigated using the nematode Caenorhabditis elegans. To estimate the degree of salt chemotaxis learning, nematodes were placed in a mixed solution of NaCl and caffeine, and then the chemotaxis index of NaCl was obtained from the nematodes placed on agar medium after pre-exposure to caffeine concentrations of 0.01, 0.1, 0.3, and 1.0%. Locomotor activity and preference behavior for caffeine were also estimated under these caffeine conditions. Nematodes pre-exposed to 0.3% caffeine showed inhibition of salt chemotaxis learning. Additional experiments indicated that nematodes showed a preference response to the middle concentration of caffeine (0.1%), with preference behavior declining in the 0.3% caffeine condition. Stable locomotor activity was observed under 0.01-0.3% caffeine conditions. These results suggest that salt chemotaxis learning with 0.3% caffeine is useful for investigating the effects of caffeine on learning in nematodes.
a Division of Thermo-Biosystem Relations , United Graduate School of Agricultural Science, Iwate University , Morioka , Japan.|b Department of Biophysics , Molecular Imaging Center, National Institute of Radiological Sciences , Chiba , Japan.
Takuya
T
Urushihata
a Division of Thermo-Biosystem Relations , United Graduate School of Agricultural Science, Iwate University , Morioka , Japan.
Hiroyuki
H
Takuwa
c Faculty of Engineering, Department of Chemistry and Biosciences , Iwate University , Morioka , Japan.
Yukako
Y
Higuchi
c Faculty of Engineering, Department of Chemistry and Biosciences , Iwate University , Morioka , Japan.
Kazumi
K
Sakata
c Faculty of Engineering, Department of Chemistry and Biosciences , Iwate University , Morioka , Japan.
Tokumitsu
T
Wakabayashi
b Department of Biophysics , Molecular Imaging Center, National Institute of Radiological Sciences , Chiba , Japan.
Asuka
A
Nishino
a Division of Thermo-Biosystem Relations , United Graduate School of Agricultural Science, Iwate University , Morioka , Japan.|b Department of Biophysics , Molecular Imaging Center, National Institute of Radiological Sciences , Chiba , Japan.|c Faculty of Engineering, Department of Chemistry and Biosciences , Iwate University , Morioka , Japan.
Tetsuya
T
Matsuura
D000818:Animals; D017173:Caenorhabditis elegans / Q000378:metabolism / Q000502:physiology*; D002110:Caffeine / Q000494:pharmacology*; D002633:Chemotaxis / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007858:Learning / Q000187:drug effects; D008124:Locomotion / Q000187:drug effects; D012965:Sodium Chloride / Q000378:metabolism; D055697:Taste Perception / Q000187:drug effects* / Q000502:physiology*
D002110:Caffeine; D012965:Sodium Chloride
C. elegans; caffeine; chemotaxis; learning function