Harderian vs nictitans gland #614

cmungall opened this Issue Nov 29, 2014 · 1 comment


None yet
1 participant

cmungall commented Nov 29, 2014

We can subdivide ocular glands in to medial and lateral (depending on location relative to canthi), with the medial subdivided into Harderian and nictitans, ie

  • ocular gland
    • medial
      • Harderian
      • nictitans
    • lateral
      • lacrimal

In doi:10.1007/978-3-642-76685-5_2 (1992) Siskai claims that Harderian and nictitans are often confused. When we see the label "Harderian" we should conservatively assume medial ocular. Siskai proposes a form subdivision based on composition of secretion - lipid in Harderian, glycoprotein in nictitans.

Latest changes to MP are based on http://www.ncbi.nlm.nih.gov/pubmed/8843648,
the retroocular sebaceous gland found within the orbit of mammals that possess a nictitating membrane (“third eyelid); the chief products of the gland vary between different groups of vertebrates, and epithelial cells possess granules or vacuoles whose contents may be mucous, serous or lipid; in rodents, the Harderian gland is especially large and secretes lipids (by a merocrine mechanism), melatonin and porphyrins; ascribed functions include a role in lubrication and protection for the eyeball and nictitating membrane (by lipids), photoprotection (by porphyrin), photoreception (by regulation of the incidence of light on the retina), and thermoregulation (in some rodents)

This is different from Siskai's definition. But I have not yet either full text, this tracker issue is a placeholder for ongoing work.

cmungall added a commit that referenced this issue Nov 29, 2014

lacrimal, harderian and nictitans glands changes
Adopting Siskai scheme pending further comments.
See issue #614

Also: minor changes to hair

This comment has been minimized.

Show comment
Hide comment

cmungall Nov 29, 2014


btw, BTO classifies Harderian as a subclass of lacrimal - we used to follow this, but no longer do this


cmungall commented Nov 29, 2014

btw, BTO classifies Harderian as a subclass of lacrimal - we used to follow this, but no longer do this

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment