PMID- 11451423
OWN - NLM
STAT- MEDLINE
DCOM- 20010920
LR  - 20191105
IS  - 0166-445X (Print)
IS  - 0166-445X (Linking)
VI  - 54
IP  - 1-2
DP  - 2001 Sep
TI  - 7-Ethoxyresorufin O-deethylase induction in rainbow trout gill epithelium 
      cultured on permeable supports: asymmetrical distribution of substrate 
      metabolites.
PG  - 29-38
AB  - The induction of 7-ethoxyresorufin O-deethylase (EROD) has been measured in 
      cultured epithelia from rainbow trout gills. Epithelia incubated with water on 
      the apical side and culture media at the basolateral side were exposed to 
      2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), beta-naphthoflavone (betaNF), 
      benzo[k]fluoranthene (B(k)F), and 3,3',4,4',5-pentachlorobiphenyl (PCB#126) from 
      the water. EROD activity was measured as the formation of resorufin from 
      7-ethoxyresorufin over time in intact epithelia. The EC(50) values obtained after 
      24 h of exposure (mean+/-S.D.) were for TCDD (n=9) 4.1+/-3.2x10(-11) M, for 
      betaNF (n=6) 1.6+/-3.8x10(-9) M, for B(k)F (n=4) 5.4+/-3.0x10(-9) M and for 
      PCB#126 (n=4) 6.15+/-10.1x10(-9) M. When assaying for EROD activity, it was found 
      that the resorufin concentrations differed between the apical and the basolateral 
      compartments, indicating an asymmetrical distribution of the enzymatically formed 
      resorufin molecules. Generally, the resorufin concentration was highest in the 
      basolateral compartment, but there were differences between epithelia obtained 
      from different fish individuals. Of a total of 13 preparations 10 had the highest 
      resorufin concentration in the basolateral compartment, while in three 
      preparations, the resorufin was uniformly distributed or slightly higher in the 
      apical compartment. The reasons for this asymmetrical distribution of substrate 
      metabolites are not known, and the addition of multidrug resistance inhibitors 
      (verapamil and cyclosporin A) did not alter the asymmetrical pattern. The 
      transepithelial electrical resistance (TER) was also measured to diagnose the 
      tightness of the epithelia. The change from culture media to experimental water 
      (containing TCDD, betaNF, or DMSO as control) in the apical compartment resulted 
      in a large increase in TER, followed by a decline, measured after 24 h. The 
      cytochrome P450 1A (CYP1A) inducers had no effect on the TER and were judged, 
      therefore, not to affect the tightness of the epithelia.
FAU - Carlsson, C
AU  - Carlsson C
AD  - Department of Environmental Toxicology, Uppsala University, Norbyvagen 18 A, 
      S-752 36 Uppsala, Sweden. carina.carlsson@ebc.uu.se
FAU - Part, P
AU  - Part P
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Netherlands
TA  - Aquat Toxicol
JT  - Aquatic toxicology (Amsterdam, Netherlands)
JID - 8500246
RN  - EC 1.14.14.1 (Cytochrome P-450 CYP1A1)
SB  - IM
MH  - Animals
MH  - Cytochrome P-450 CYP1A1/*biosynthesis
MH  - Drug Resistance, Multiple
MH  - Electric Impedance
MH  - Enzyme Induction
MH  - Epithelial Cells
MH  - Gills/*enzymology
MH  - Oncorhynchus mykiss/*metabolism
EDAT- 2001/07/14 10:00
MHDA- 2001/09/21 10:01
CRDT- 2001/07/14 10:00
PHST- 2001/07/14 10:00 [pubmed]
PHST- 2001/09/21 10:01 [medline]
PHST- 2001/07/14 10:00 [entrez]
AID - S0166-445X(00)00184-3 [pii]
AID - 10.1016/s0166-445x(00)00184-3 [doi]
PST - ppublish
SO  - Aquat Toxicol. 2001 Sep;54(1-2):29-38. doi: 10.1016/s0166-445x(00)00184-3.