Ultrastructural study of sheep lacrimal glands.
Sheep lacrimal glands are mixed glands, consisting of tubulo-acinar units succeeded by ducts of simple morphology. The secretory portions consist of three cell types: mucous, seromucous and serous, which may be intermingled in the same acinus or may form acini wholly made of only serous or mucous cells. Mucous cells show a rough endoplasmic reticulum that is reduced to a few cisternae located near the cell base and among the interstices of the secretory droplets. Mucous granules appear uniformly electron-lucent. Serous cells display a typical structure; serous granules can be uniformly electron-dense or composed of dense inclusions dispersed in an electron-lucent matrix. The seromucous granules have a bizonal substructure: a dense core is embedded in a highter matrix. Secretory acini are succeeded by intercalated ducts; the epithelium of these ducts gradually increases in height to form a kind of excretory duct, without the intervention of striated ducts.
Gargiulo
A M
AM
Istituto di Anatomia degli Animali Domestici, Perugia, Italy. anatvet@unipg.it
Coliolo
P
P
Ceccarelli
P
P
Pedini
V
V
D000818:Animals; D003594:Cytoplasmic Granules / Q000648:ultrastructure*; D005260:Female; D007765:Lacrimal Apparatus / Q000166:cytology / Q000648:ultrastructure*; D008297:Male; D008854:Microscopy, Electron; D012756:Sheep / Q000033:anatomy & histology*