Measuring serotonin distribution in live cells with three-photon excitation.
Tryptophan and serotonin were imaged with infrared illumination by three-photon excitation (3PE) of their native ultraviolet (UV) fluorescence. This technique, established by 3PE cross section measurements of tryptophan and the monoamines serotonin and dopamine, circumvents the limitations imposed by photodamage, scattering, and indiscriminate background encountered in other UV microscopies. Three-dimensionally resolved images are presented along with measurements of the serotonin concentration ( approximately 50 mM) and content (up to approximately 5 x 10(8) molecules) of individual secretory granules.
Maiti
S
S
School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA.
Shear
J B
JB
Williams
R M
RM
Zipfel
W R
WR
Webb
W W
WW
D000818:Animals; D002470:Cell Survival; D003594:Cytoplasmic Granules / Q000737:chemistry*; D004298:Dopamine / Q000032:analysis; D007834:Lasers; D008856:Microscopy, Fluorescence / Q000295:instrumentation / Q000379:methods*; D010777:Photochemistry; D017785:Photons; D051381:Rats; D012701:Serotonin / Q000032:analysis*; D014364:Tryptophan / Q000032:analysis; D014407:Tumor Cells, Cultured; D014466:Ultraviolet Rays
D012701:Serotonin; D014364:Tryptophan; D004298:Dopamine