Cardiac and hepatic effects of pre- and postnatal exposure to polybrominated biphenyls in rats

Area of Science:

• Toxicology
• Environmental Health
• Pharmacology

Background:

• Polybrominated biphenyls (PBBs) are persistent organic pollutants with known toxic effects.
• Understanding the specific impacts of PBBs on organ systems is crucial for risk assessment.

Purpose of the Study:

• To investigate the effects of pre- and postnatal polybrominated biphenyls (PBBs) exposure on Sprague-Dawley rats.
• To assess the impact of PBBs on body weight, liver function, and cardiac function.

Main Methods:

• Sprague-Dawley rats were exposed to 100 ppm of polybrominated biphenyls (PBBs) pre- and postnatally.
• Evaluated body weight gain, liver weight to body weight ratio, hepatic vitamin A concentrations, and hepatic delta-aminolevulinic acid (ALA) synthetase activity.
• Measured urinary excretion of uro- and coproporphyrins and assessed cardiac contractile function, including inotropic responses to calcium and ouabain.

Main Results:

• PBBs exposure significantly reduced body weight gain and hepatic vitamin A concentrations.
• Increased liver weight to body weight ratio, hepatic delta-aminolevulinic acid (ALA) synthetase activity, and urinary uro- and coproporphyrin excretion were observed.
• PBBs enhanced the left atrial inotropic response to calcium but did not affect adrenergic neuronal transport, baselike peak tension, or ouabain response in the heart.

Conclusions:

• Pre- and postnatal PBBs exposure retards body weight gain and induces significant alterations in liver function and porphyrin metabolism in rats.
• Cardiac contractile function was largely unaffected by PBBs exposure, suggesting organ-specific toxicity.