Premium
Cell generation within the interdental gingival septum of the rat
Author(s) -
Pender N.,
Heaney T. G.
Publication year - 1994
Publication title -
journal of periodontal research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.31
H-Index - 83
eISSN - 1600-0765
pISSN - 0022-3484
DOI - 10.1111/j.1600-0765.1994.tb01086.x
Subject(s) - molar , connective tissue , interdental consonant , chemistry , anatomy , major duodenal papilla , biology , pathology , dentistry , medicine
The aims of this investigation were to determine whether connective tissue progenitor cells in the interdental gingival septum (IGS) have a paravascular origin, and how the distribution of 3 HTdR‐labelled cells within the IGS changes with time after a single injection. 30 male hooded Lister rats aged 6 weeks, were killed in groups of ten, 3, 75 and 171 h after a single injection of tritiated thymidine. Autoradiographs were examined of 3 transverse Historesin sections of the papilla between second and third mandibular molars in 29 specimens, taken at equidistant intervals between the col and alveolar bone crest. At all times and levels, 73.9–93.0% of labelled cells and 72.0–79.0% of unlabelled cells lay within 50 μm of blood vessels (BVs). The highest percentages of labelled cells (PLCs) occurred within 5 μm of BVs (P < 0.001) although mean nuclear density here was lowest (P < 0.017), and there was a significant diminution of PLC (P < 0.05) with increasing distance from BVs, occurring most precipitously 5–10 μ from vessel walls. Sites of significantly increased PLC at 3 h also approximated to sites in which mean BV densities were greatest. At 3 h, a number of discrete sites with significantly increased PLCs (P < 0.05) were found within two zones, each equivalent to 40% of IGS volume and juxtaposed with each tooth. At later times, additional sites of raised PLC appeared throughout the IGS. Overall PLCs in the upper two levels and within 5 μm of BVs also increased over the timecourse (P < 0.01). These data are consistent with the existence of paravascular connective tissue progenitor cells within the outer zones of the IGS closest to the teeth. Labelled cell distributions at 75 h and 171 h did not provide firm evidence of translocation within the IGS.