TY - JOUR
T1 - Congener-specific effects of PCBs on contractions of pregnant rat uteri
AU - Tsai, Mei Ling
AU - Webb, R. Clinton
AU - Loch-Caruso, Rita
N1 - Funding Information:
Acknowledgment-s The authors thank Shelly Coe and Howard Lis-topad for their assistancew ith thesee xperimentsa nd Dr. Craig Harris for providing uterine tissue. The project described was conducted as partial fulfillment of M.-L. Tsai’s doctoral dissertationa nd was supported by grant number HL18575 to R. C. Webb and P42 ES0491 1 to R. Loch-Caruso from the National Heart, Lung, and Blood Institutea nd the National Institute of Environmental Sciences, respectively,o f the NIH. Additional supportw as provided by the Laboratory Animal Cores of the Center for the Study of Reproduction, which is supported by grant numberP 30 HD18258 from the National Instituteo f Child Health and Human Development,N IH.
PY - 1996
Y1 - 1996
N2 - Both increased and decreased gestation lengths have been reported following exposures to polychlorinated biphenyl (PCB) mixtures and congeners. Because oscillatory uterine contractions are essential for parturition, we hypothesized that the disparate findings on gestation length may be the result of distinct PCB congener-specific actions on oscillatory uterine contractions. This study examined the acute effects of PCB congeners on isometric contractions of isolated pregnant uteri and the structure-activity relationship for individual congeners. After cumulative exposure to individual PCB congeners (0.5 μM to 150 μM), oscillatory contractions were: 1) not altered by 2,4,5,2′,4′,5′-hexachlorobiphenyl, 3,4,5,3′,4′-pentachlorobiphenyl, or 3,4,3′,4′-tetrachlorobiphenyl; 2) significantly inhibited by 4-hydroxy-2′,4′,6′-trichlorobiphenyl; and 3) markedly increased by 2,4,6-trichlorobiphenyl and 2,4,2′,4′-tetrachlorobiphenyl, when compared to solvent controls. The uteri were more sensitive to PCB congeners with ortho-substituted light chlorination than those highly chlorinated, or those interacting with the Ah-receptor.
AB - Both increased and decreased gestation lengths have been reported following exposures to polychlorinated biphenyl (PCB) mixtures and congeners. Because oscillatory uterine contractions are essential for parturition, we hypothesized that the disparate findings on gestation length may be the result of distinct PCB congener-specific actions on oscillatory uterine contractions. This study examined the acute effects of PCB congeners on isometric contractions of isolated pregnant uteri and the structure-activity relationship for individual congeners. After cumulative exposure to individual PCB congeners (0.5 μM to 150 μM), oscillatory contractions were: 1) not altered by 2,4,5,2′,4′,5′-hexachlorobiphenyl, 3,4,5,3′,4′-pentachlorobiphenyl, or 3,4,3′,4′-tetrachlorobiphenyl; 2) significantly inhibited by 4-hydroxy-2′,4′,6′-trichlorobiphenyl; and 3) markedly increased by 2,4,6-trichlorobiphenyl and 2,4,2′,4′-tetrachlorobiphenyl, when compared to solvent controls. The uteri were more sensitive to PCB congeners with ortho-substituted light chlorination than those highly chlorinated, or those interacting with the Ah-receptor.
KW - Polychlorinated biphenyls
KW - Rats
KW - Smooth muscle
KW - Spontaneous oscillations
KW - Uterine contraction
KW - Uterus
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U2 - 10.1016/0890-6238(95)02014-4
DO - 10.1016/0890-6238(95)02014-4
M3 - Article
C2 - 8998381
AN - SCOPUS:0030061994
SN - 0890-6238
VL - 10
SP - 21
EP - 28
JO - Reproductive Toxicology
JF - Reproductive Toxicology
IS - 1
ER -