CHLORIDE SECRETION IN THE SUBMANDIBULAR-GLAND OF ADULT AND EARLY POSTNATAL RATS STUDIED BY X-RAY-MICROANALYSIS

Citation
Ac. Mork et al., CHLORIDE SECRETION IN THE SUBMANDIBULAR-GLAND OF ADULT AND EARLY POSTNATAL RATS STUDIED BY X-RAY-MICROANALYSIS, HISTOCHEM C, 105(4), 1996, pp. 297-303
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell Biology",Microscopy
Journal title
HISTOCHEMISTRY AND CELL BIOLOGY
ISSN journal
0948-6143 → ACNP
Volume
105
Issue
4
Year of publication
1996
Pages
297 - 303
Database
ISI
SICI code
0948-6143(1996)105:4<297:CSITSO>2.0.ZU;2-V
Abstract
Submandibular acinar cells of 1-day-old, 7-day-old, and adult rats wer e analyzed with X-ray microanalysis after stimulation with carbachol f or different time periods (2-7 min). In unstimulated animals, marked d ifferences in elemental content between compartments could be observed : secretory granules had a higher Ca and lower P and K content than ot her cell compartments. Comparison between different age groups showed significant differences for Ca, which increased with age in all compar tments; Mg increased with age in the secretory granules and the apical cytoplasm. Only the glands from adult animals showed a significant ef fect of cholinergic stimulation: a transient decrease in Cl and K. The Cl concentration in the secretory granules decreased to 60% of the co ntrol value, which suggests that the granules release Cl upon stimulat ion. In young animals, no or little change in elemental distribution w as observed after stimulation. This may indicate that Cl- secretion me chanisms are much less prominent in young animals. The ultra structure of submandibular secretory granules depends on the preparation method : condensed and electron-dense in freeze-substituted unfixed tissue, d econdensed and more translucent in aldehyde-fixed tissue. This may ind icate that the granules can transport water, and swell during the proc ess of aldehyde fixation.