Excessive stimulation of serotonin2 (5-HT2) receptors during late development of chicken embryos causes decreased embryonic motility, interferes with hatching, and induces herniated umbilici.

摘要: Abstract The existence and functional significance of 5-HT2 receptors in chicken embryos was studied by injecting the selective agonist dimethoxyiodophenylaminopropane (DOI), alone or conjunction with antagonist ritanserin (RIT), into domestic eggs varying ages. DOI caused dose-dependent reductions hatchability herniated umbilici hatchlings. These effects were observed after injection early, mid, late during embryonic development, evidence toxic being greater older embryos, probably due to receptor activation even as early on day 3 embryogenesis. This is based upon fact that injected continued develop apparently normally, failing hatch, often pipping their shells. Additionally, those hatched did so umbilici, late-exposed indicating DOI's this organ most likely mediated prehatching period (i.e., days 18–20). agonist's selectivity confirmed capacity RIT dose dependently block both these DOI. Reduced motility monitored 19, evening 18, suggests excessive development species interferes some normal behaviors physiological changes neccessary for inducing and/or maintaining hatching process.