Summary
The fact that the atrial gland ofAplysia californica contains peptides that will induce egg laying when injected into mature animals prompts consideration of the role played by the gland in the normal physiology of the animal. We have approached this consideration with a combination of morphologic and physiologic investigations. Morphologic study reveals the gland as a stratified epithelium comprised of three cell types. The only evidence for secretory activity was seen in the columnar epithelial cells containing large vesicular inclusions. These cells appear to discharge their secretory product into the lumen of the large hermaphroditic duct. While we cannot specify the contents of the secretion from the columnar cells, perfusate of the duct lumen contained bioassay active material only when the duct was exposed to depolarizing conditions. Though additional experiments in which exogenously administered atrial gland peptides were found to initiate egg laying in animals from which the source of the egg laying neurohormone had been extirpated, it appears likely that the atrial gland substances are not endocrine factors. Instead, their function must be sought among the exocrine products of the duct epithelium.
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Abbreviations
- FWS :
-
filtered artificial sea water
- LHD :
-
large hermaphroditic duct
References
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Technical assistance for these studies was ably provided by Eugene Dannen and Gary Whitney. The surgical procedures were developed by Greg Thayer. Funding for the work was provided by NIH grant NS 11149 to S.A.
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Arch, S., Lupatkin, J., Smock, T. et al. Evidence for an exocrine function of theAplysia atrial gland. J. Comp. Physiol. 141, 131–137 (1980). https://doi.org/10.1007/BF00611886
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DOI: https://doi.org/10.1007/BF00611886