title: Age-related alterations in the lacrimal gland of adult albino rat: a light and electron microscopic study.
abstract: BACKGROUND
  Age related changes in the lacrimal gland are associated with alterations in the structural organization and functional response in the gland of diverse mammalian species. Dry eye syndrome is one of the most common ocular problems in the world especially in old age. It results when the lacrimal gland fails to secrete proteins and fluid in sufficient quantity or appropriate composition.
  
  
  OBJECTIVE
  The present study is designed to demonstrate the influence of aging on the structure of the lacrimal gland of albino rat and to provide a morphological basis to explain the pathogenesis of the dry eye syndrome with ageing. It also aims to carry out a comparative analysis of age-dependent changes in male and female rats and to address how the lacrimal gland ages in each sex.
  
  
  METHODS
  Eighty albino rats were used in this study. The animals were divided into two age groups, young adult and senile. Tear secretion was measured using a modified Schirmer test. Corneal impression cytology of the anesthetized rats was done. The glands were subjected to gross morphologic examination, microscopic examination using H&E, PAS, Masson's trichrome and Giemsa stains. Electron microscopic examination was done in addition to quantitative histomorphometric estimations included acinar density, ductal count and mast cell count.
  
  
  RESULTS
  Light microscopic examination of the lacimal glands of the senile rats revealed different pathological changes. These included acinar, ductal as well as stromal changes. Electron microscope examination of the lacrimal gland of the senile group showed a decrease in the electron dense secretory vesicles, mitochondrial swelling and lipofuscin-like inclusions were frequently seen in the cytoplasm of acinar cells in senile rats.
  
  
  CONCLUSIONS
  The structural changes in the lacrimal glands of senile rats were associated with reduction in tear secretion as well as alterations in corneal epithelium. Gender difference in lacrimal gland structure was recorded.
authors.affiliation: Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Egypt.
authors.forename: Amina B
authors.initials: AB
authors.lastname: El-Fadaly
authors.affiliation: Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Egypt. Electronic address: ehab.elshaarawy@kasralainy.edu.eg.
authors.forename: Ehab A A
authors.initials: EA
authors.lastname: El-Shaarawy
authors.affiliation: Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Egypt.
authors.forename: Ayman A
authors.initials: AA
authors.lastname: Rizk
authors.affiliation: Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Egypt.
authors.forename: Mogeda M
authors.initials: MM
authors.lastname: Nasralla
authors.affiliation: Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Egypt.
authors.forename: Doaa M A
authors.initials: DM
authors.lastname: Shuaib
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D002452:Cell Count; D003094:Collagen / Q000378:metabolism; D005260:Female; D007249:Inflammation / Q000473:pathology; D007765:Lacrimal Apparatus / Q000033:anatomy & histology / Q000254:growth & development* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D017208:Rats, Wistar; D012727:Sex Characteristics
chemical_list: D003094:Collagen
keywords: Aging; Cytology; Histology; Lacrimal gland; Pathology