Placental transport of brevetoxin-3 in CD-1 mice.
The purpose of this study was to examine the distribution of brevetoxin-3 administered to pregnant dams and to determine the extent of placental transport to fetuses. Twenty-nine pregnant CD-1 mice were administered (3)H-brevetoxin-3 ( approximately 1.3 microCi/animal; approximately 2.8 microg compound/kg) by intratracheal instillation on one of gestational days 15-18. Groups of four or five dams were killed at selected times through 48 h post-dosing. Four pregnant dams were administered (3)H-brevetoxin-3 on gestational day 15 or 16 via osmotic minipump to provide continuous delivery of compound ( approximately 0.13 microCi, 7.5 ng compound/day) over a 72-h period. Then the dams and fetuses were killed. Brevetoxin-associated radioactivity was detected in placentas and fetuses within 0.5h of intratracheal administration. Concentrations of brevetoxin equivalents in fetuses were approximately 0.3 ng/g throughout the 48-h post-dosing, resulting in a calculated dose to fetuses of 19 ng/gh. Following brevetoxin infusion, concentration of brevetoxin equivalents in fetuses was 0.1 ng/g, lower than that present in most maternal tissues. Results demonstrated placental transport of brevetoxin or its metabolites following maternal acute exposure and repeated low-dose exposure. The consequences of these findings for pregnant women exposed to brevetoxins by inhalation or ingestion remain to be determined.
Benson
Janet M
JM
Lovelace Respiratory Research Institute, 2425 Ridgecrest Dr. SE., Albuquerque NM 87108, USA. jbenson@LRRI.org
Gomez
Andrea P
AP
Statom
Gloria L
GL
Tibbetts
Brad M
BM
Fleming
Lora E
LE
Backer
Lorraine C
LC
Reich
Andrew
A
Baden
Daniel G
DG
D000818:Animals; D001692:Biological Transport; D005260:Female; D005333:Fetus / Q000737:chemistry / Q000378:metabolism; D008387:Marine Toxins / Q000378:metabolism*; D008431:Maternal-Fetal Exchange; D051379:Mice; D008815:Mice, Inbred Strains; D035964:Oxocins / Q000378:metabolism*; D010920:Placenta / Q000737:chemistry / Q000378:metabolism*; D011247:Pregnancy; D000095702:Polyether Toxins
D008387:Marine Toxins; D035964:Oxocins; C502852:brevetoxin 3, Karenia brevis; D000095702:Polyether Toxins