Environmental Thyroid Endocrine Disruption in Shiner Perch (Cymatogaster aggregata)| An Analysis of Thyroid Glandular Function

• Main Author: Lee, Evan B.
• Language: EN
• Published: California State University, Long Beach 2017
• Subjects: Biology|Endocrinology|Environmental health
• Online Access: http://pqdtopen.proquest.com/#viewpdf?dispub=10603921

<p> Industrialized and developed urban centers surround the aquatic ecosystem of San Francisco Bay, and are historic and current sources of anthropogenic contaminants to which resident wildlife is exposed and impacted. An indigenous fish species, the shiner perch (Cymatogaster aggregata), was demonstrated to exhibit significant reductions in plasma tetraiodothyronine (T4) concentrations when sampled from highly industrial Oakland Inner Harbor (OAK) as compared with less impacted locations like Redwood City (RED). This study combined histomorphological evaluation of thyroid follicular tissues and characterization of plasma thyroid hormones, T4 and triiodothyronine (T3). Fish from OAK, but not RED, exhibited reduced plasma T4, T3, and total thyroid hormones, changes that were significantly correlated with thyroid glandular changes including reduced follicular colloid sizes. The findings indicate environmental disruption of thyroid hormone biosynthesis and possible thyroid gland compensatory responses (to low thyroid hormone levels) given the reduced colloid volumes.</p><p>