Impairment of rat tooth eruption in pups born to mothers exposed to chronic stress during pregnancy

• Autores: Fontanetti PA; DeLucca R; Mandalunis PM; Vermouth NT
• Año de publicación: 2013
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: CONSTANT LIGHT; PRENATAL STRESS; BONE HISTOMORPHOMETRY; TOOTH ERUPTION; BONE VOLUME; OSTEOCLASTS
• Institución: Universidad Nacional de Córdoba

Objective: Tooth eruption is a multifactorial process in which bone tissue plays a prevailing
role. In this study we evaluated the bone overlying the developing tooth germ and the degree
of tooth eruption of the first mandibular molar in pups born to mothers subjected to
constant light during pregnancy.
Design: Pregnant rats were divided into two groups: mothers chronically exposed to a 12:12
light/light cycle (LL) from day 10 to 20 of pregnancy and controls (C) maintained on a 12:12 h
light/dark cycle. Pups from each group were euthanized at the age 3 or 15 days.
Buccolingually oriented sections of mandibles were stained with haematoxylin?eosin or
for histochemical detection of tartrate resistant acid phosphatase (TRAP). The histomorphometric
parameters evaluated were bone volume, number of osteoclasts, TRAP+ bone
surface, number of TRAP+ and TRAP osteoclasts per mm2 and degree of tooth eruption
(mm).
Results: It was found an increase in bone volume (LL: 58.14 4.24 vs. C: 32.31 2.16; p < 0.01)
and a decrease in the number of osteoclasts (LL: 3.5 0.65 vs. C: 8.03 1.31; p < 0.01) and
TRAP+ cells (LL: 0.84 0.53 vs. C: 8.59 1.26; p < 0.01) in 3-day-old pups born to LL-exposed
mothers. These observations are consistent with the decrease in the degree of tooth eruption
observed in 15-day-old experimental pups (LL: 0.605 0.05 vs. C: 0.342 0.02; p < 0.0001).
Conclusion: Our results suggest that chronic constant light applied as a pre-natal stressor
impairs the resorptive capacity of osteoclasts involved in the formation of the eruption
pathway and consequently the degree of tooth eruption.
http://www.sciencedirect.com/science/article/pii/S0003996913002707#
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Biología Celular, Microbiología