Thermal modulation of the toxicokinetics of benzo[a]pyrene in isolated hepatocytes of sablefish (Anoplopoma fimbria), black rockfish (Sebastes melanops), and chub mackerel (Scomber japonicus).
Hepatocytes from sablefish (Anoplopoma fimbria), black rockfish (Sebastes melanops) and chub mackerel (Scomber japonicus) were isolated from 11 degrees C acclimated animals. The uptake, metabolism, and excretion of benzo[a]pyrene (B[a]P) in hepatocytes was measured at 6, 11 and 19 degrees C. Chub mackerel hepatocyte uptake rates were significantly lower (0.012 +/- 0.003 microg/s per g cell) at 11 degrees C than black rockfish (0.028 +/- 0.009 microg/s per g cell) or sablefish (0.032 +/- 0.012 microg/s per g cell) hepatocytes at all temperatures. Hepatocytes metabolized B[a]P to phase I (1-8%) and phase II (92-99%) metabolites. Accumulation of phase II metabolites was lower in chub mackerel hepatocytes (0.016 +/- 0.004 microg/h per g cell), than black rockfish (0.052 +/- 0.012 microg/h per g cell), or sablefish hepatocytes (0.060 +/- 0.015 microg/h per g cell). Phase II metabolite accumulation increased greatest with temperature in chub mackerel hepatocytes (Q10 = 1.94 +/- 0.30), followed by sablefish (Q10 = 1.65 +/- 0.30), and rockfish (Q10 = 1.38 +/- 0.30). Sablefish hepatocytes had higher excretion rates of phase II metabolites (0.010 +/- 0.0023 microg/h per g cell), than mackerel (0.0046 +/- 0.0009 microg/h per g cell) or rockfish hepatocytes (0.0029 +/- 0.0008 microg/h per g cell). Phase II metabolite excretion rates increased with temperature only in sablefish hepatocytes (Q1O = 1.67 +/- 0.76). These differences in toxicokinetics may indicate distinct consequences for various species exposed to xenobiotics.
Johnston
B D
BD
Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada.
Alexander
G
G
Kennedy
C J
CJ
D000818:Animals; D001564:Benzo(a)pyrene / Q000493:pharmacokinetics* / Q000633:toxicity; D002478:Cells, Cultured; D005399:Fishes / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D013696:Temperature
D001564:Benzo(a)pyrene