J Korean Assoc Oral Maxillofac Surg.  2004 Apr;30(2):85-99.

The changes of telomerase activity and proliferating cell nuclear antigen(PCNA) expression in the developmental stages of rat's upper digestive system

• Sung IY
• Kim JR

Abstract

PURPOSE: This study observed the changes in the telomerase activity, it's developmental regulation, PCNA expression, and their correlation in rat's upper digestive organs during growth and aging.
MATERIALS AND METHODS
Upper digestive organs(buccal mucosa, gingiva, palate, submandibular and parotid glands, and tongue) were aseptically removed from Sprague-Dawley rats of fetal(gestational 20 days), growing(1, 2, 3, 5, and 7 weeks after birth) and adult(12 week old). Samples for telomerase activity were frozen on liquid nitrogen immediately after sacrifice, and stored until the use at -75 degree C in order to measure it. Telomerase activity was measured by a PCR-based telomeric repeat amplication protoco(TRAP) assay and quantitated with Photometric Telo TAGGG Telomerase PCR ELISA plus(Roche Diagnostics GmbH. Mannheim. ermany). PCNA expression were measured immunohistochemistry with anti PCNA Ab-1, Clone PC10(NeoMark. California. USA).
RESULTS
1. Telomerase activities in buccal mucosa, palate and gingiva were the highest in fetus and decreased gradually or rapidly after birth and then diminished, but In salivary gland and tongue were the highest in fetus and also high at 1 week and then decreased rapidly. 2. PCNA expression in buccal mucosa, gingiva, Tongue and salivary gland was the highest in fetus and decreased gradually and then diminished. but only in palate decreased rapidly after birth and then diminished.
CONCLUSION
The highest telomerase activity of embryonic stage decreased rapidly after birth in rat's upper digestive organs. There may be a developmental regulation of telomerase activity, but not a tissue-specific. This telomerase activity seems correlated closely with PCNA expression in rat's upper digestive system.

Keyword

Telomerase; PCNA; Upper digestive system

MeSH Terms

Aging
California
Clone Cells
Digestive System*
Enzyme-Linked Immunosorbent Assay
Fetus
Gingiva
Immunohistochemistry
Mouth Mucosa
Mucous Membrane
Nitrogen
Palate
Parotid Gland
Parturition
Polymerase Chain Reaction
Proliferating Cell Nuclear Antigen
Rats, Sprague-Dawley
Salivary Glands
Telomerase*
Tongue
Nitrogen
Proliferating Cell Nuclear Antigen
Telomerase