title: Morphologic effects of in vivo acute exposure to the pesticide methoprene on the hepatopancreas of a non-target organism, Homarus americanus.
abstract: Methoprene is a pesticide widely used for mosquito control. It is an endocrine disruptor, acting as an analog of juvenile hormone. While targeting insect larvae, it also impacts non-target animals including crustaceans. Anecdotal reports suggested that methoprene has unintended effects on adult arthropods. Earlier, we documented effects in adult lobsters at the metabolic and gene expression levels. In this study we have documented morphologic corollaries to our prior observations. We examined the light and electron microscopic changes in the hepatopancreas of adult lobsters following in vivo acute exposure to methoprene. Changes by light and electron microscopy levels were evident following exposure to sub-lethal concentrations of methoprene for 24h. Tissue from exposed animals showed the formation of extensive cytoplasmic spaces (vesiculation) with disruption and loss of specific subcellular organelles. The findings provide morphologic correlates to the metabolic and genomic alterations we have observed in previous investigations.
authors.affiliation: Division of Basic Medical Sciences, Mercer University School of Medicine, 1550 College Street, Macon, GA 31207, USA.
authors.forename: Anna N
authors.initials: AN
authors.lastname: Walker
authors.forename: Ryan
authors.initials: R
authors.lastname: Golden
authors.forename: Michael N
authors.initials: MN
authors.lastname: Horst
mesh_terms: D000208:Acute Disease; D000818:Animals; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000633:toxicity*; D004781:Environmental Exposure / Q000032:analysis*; D015870:Gene Expression / Q000187:drug effects; D016678:Genome / Q000187:drug effects; D043143:Hepatopancreas / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008726:Methoprene / Q000633:toxicity*; D008854:Microscopy, Electron; D008121:Nephropidae / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D015388:Organelles / Q000187:drug effects / Q000378:metabolism; D010575:Pesticides / Q000633:toxicity*; D013997:Time Factors
chemical_list: D052244:Endocrine Disruptors; D010575:Pesticides; D008726:Methoprene