TABLE 1

Expression of c-Myc-5-HT2A-eCFP and addition of 5-HT enhances G protein activation by DAMGO and morphine

[35S]GTPγS binding studies were performed on membranes of Flp-In T-REx HEK293 cells constitutively expressing MOP-eYFP and in which c-Myc-5-HT2A-eCFP expression could be induced by addition of doxycycline. The pEC50 for DAMGO and morphine and the extent of stimulation over maximal agonist-induced binding of [35S]GTPγS produced without induction of the 5-HT2A receptor construct are shown. Parentheses indicate number of independent experiments performed. Values are presented as mean ± S.E.M. The values in parentheses represent n.




pEC50

Emax > Control
%
DAMGO
Control 7.58 ± 0.09 (8)
Doxycycline (10 ng/ml) 7.88 ± 0.16 (8) 10.59 ± 5.52 (8)
Doxycycline (10 ng/ml) 5-HT (1 μM) 7.91 ± 0.08 (8) 33.33 ± 3.69* (8)
Morphine
Control 7.63 ± 0.07 (4)
Doxycycline (10 ng/ml) 7.65 ± 0.13 (4) 7.92 ± 1.68 (4)
Doxycycline (10 ng/ml) 5-HT (1 μM)
7.92 ± 0.09 (4)
23.75 ± 4.65* (4)
  • * P < 0.001 by Dunnett's post hoc test analysis of variance.