Biomedical Engineering Reference
In-Depth Information
fluorescence retention at T3 was 15.8% for DMSO control zebrafish (2,211,762/
14,132,040
100%) and 77.4% for phenytoin-treated zebrafish (13,618,250/
17,597,328
100%).
14.3.4 Assessment of Drug Effects on Pgp Efflux
Using optimum conditions, we next quantitated effects of six drugs shown to inhibit
Pgp in mammals, verapamil, phenytoin, loperamide, RU486, quinidine, and cyclo-
sporine, and one negative drug, caffeine; 0.1% DMSO was used as vehicle control.
Three concentrations, 1, 10, and 100
M, were used for each drug. Drug treatment
and image capture and analysis were performed as described. Representative T3
images of ROI in brain in control and drug-treated animals are shown in Fig. 14.6.
After treatment with all six positive drugs, fluorescence intensity was higher than
DMSO control, indicating Pgp efflux inhibition. At T3, caffeine-treated zebrafish
m
Figure 14.6
Drug effects on
Pgp efflux. Pgp efflux was
assessed by quantitating
rho-HRP clearance from the
brain. Seven dpf zebrafish
were incubated with varying
drug concentrations for 1 h
before injecting rho-HRP
into the brain.
Representative dorsal view
images of ROI in brain at T3
are shown. At T3, all six
positive compounds,
verapamil, phenytoin,
loperamide, RU486,
quinidine, and cyclosporine,
increased fluorescence
intensity compared to
DMSO control, indicating
that these drugs inhibited
Pgp efflux. At T3, DMSO-
and caffeine-treated
zebrafish exhibited low
fluorescence intensity,
indicating no Pgp efflux
inhibition. Anterior to the
left. White scale bar is
100 mm.
Search WWH ::
Custom Search