RESUMO
It is well documented that various organs and tissues in the body show a differential, non-homogeneous pattern of development and aging. The present study evaluates some of the morphological and metabolic changes characterizing the aging of different types of cartilages in normal male mice. Representatives of hyaline, fibrous, articular and elastic types of cartilage were obtained from animals ranging from 1 week to 1 year of age. Our determinations included the following: total body and organ weights, proteins and DNA concentrations, [3H]leucine and [35S]sulfate uptake. The biochemical assays were accompanied by morphological examinations of corresponding tissue specimens. This investigation clearly indicates that the growth and maturational activities of the various cartilages examined attained their completion at a very early stage of life (1-3 months postnatally). Thereafter, a phase of steady state prevails, followed by a gradual but continuous decline in the various metabolic activities. The morphological findings illustrate the nature of the age-related structural changes. The present findings indicate that a skeletal tissue such as cartilages of various types, tends to age early during the lifespan of the animal.
Assuntos
Envelhecimento , Cartilagem/crescimento & desenvolvimento , Animais , Peso Corporal , Cartilagem/anatomia & histologia , Cartilagem/metabolismo , DNA/metabolismo , DNA/fisiologia , Disco Intervertebral/anatomia & histologia , Disco Intervertebral/crescimento & desenvolvimento , Disco Intervertebral/metabolismo , Masculino , Côndilo Mandibular/anatomia & histologia , Côndilo Mandibular/crescimento & desenvolvimento , Côndilo Mandibular/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Tamanho do Órgão , Sulfatos/metabolismo , Processo Xifoide/anatomia & histologia , Processo Xifoide/crescimento & desenvolvimento , Processo Xifoide/metabolismoRESUMO
The xiphisternal cartilages of newborn, suckling, immature and adult guinea-pigs were divided into twelve regions in a study of their histology and intracellular lipid content. Histochemical methods were employed, and the observations quantified using a semi-automatic image analyser. In general, triglyceride content increases with age and is lower in surface layers and in distal and lateral regions than in deep layers and proximal and medial regions. Phospholipids, on the other hand, diminish with age and are most abundant in surface layers and in distal and lateral regions. The nature and quantity of these lipids in the various regions and layers into which the cartilages were subdivided has been related to the size of the lacunae in which the cells lie.
