Age-related changes in the hamster epididymis

Abstract

Reproductive ability is decreased in aged animals and in men. Little is known about the changes taking place in the epididymis, and the possible influence on the loss of sperm quality. We studied the age-related alterations in the epididymis and in epididymal spermatozoa of hamsters. Adult (6-month-old), middle-aged (18-month-old), and aged (24-month-old) hamsters were used. Serum samples were obtained to determine testosterone levels. Testes and epididymides were removed and studied by light and electron microscopy. Epididymal sperm was also obtained and the motility, position of cytoplasmic droplet, and concentration were evaluated. Measurements of the height of the epithelium, length of stereocilia, external tubular diameter, and thickness of the muscular wall were performed. The proliferative activity was also studied. An ANOVA analysis was used to compare quantitative differences between epididymal zones and age groups. Aged hamsters presented involutive changes in the epididymis. A decrease in tubular diameter was found in cauda; principal cell ultrastructure showed changes including the appearance of damaged mitochondria, bundles of filaments, and the accumulation of lipofuscin. Some clear cells showed an unusual morphology by the presence of large electrondense vacuoles. A reduction in sperm quality was also observed, including a decrease in sperm motility and concentration, and alterations in the migration of sperm cytoplasmic droplet. Testosterone levels and cellular proliferative activity did not change. Aging causes a morphological alteration of hamster epididymis (mainly in the cauda), and a decrease in sperm quality.

Association between Age and Epididymal and Accessory Sex Gland Function and their Relation to Sperm Motility

“…These changes mainly affect the cauda epididymidis. Thickening of the basement membranes as indicated by a narrower luminal diameter and an ultrastructural alteration of principal cells and some clear cells are the essential changes found in the cauda [Serre and Robaire 1998;Calvo et al 1999]. Similar changes have been reported to follow castration of the prepubertal rat [Delongeas et al 1987].…”

The Possible Protective Role of Cabbage Seed Extract Against Effect of Gamma Rays on Rat Cauda Epididymis and Epididymal Sperms

“…Measurments were taken by light microscopy with a precalibrated eye-piece micrometer according to Calvo et al (1999). The percent value of the mean of radiated relative to non radiated group was calculated and graphically presented using Microsoft Excel.…”

Estudo ultraestrutural do desenvolvimento da espermatogênese e da via espermática de preás (Galea spixii, Wagler, 1831) criados em cativeiro

“…Nos mamíferos o epidídimo caracteriza-se por ser um tubo enovelado, dividido em três áreas distintas na maioria das espécies: cabeça, receptora de espermatozóides e fluídos dos túbulos eferentes; o corpo, que conecta a cabeça a cauda; e a cauda, a qual armazena os espermatozóides antes da ejaculação (BARONE et al, 1973;MATAMOROS, 1981;BORGES, 2004;MARTUCCI et al, 2006 No rato, camundongo isogênico e no hamster este órgão dividia-se em cinco segmentos, porém no rato o segmento I, o epitélio alto e torna-se sucessivamente mais baixo nos segmentos posteriores, ocorrendo o inverso com relação à quantidade de espermatozóides no lúmen do tubo, o qual aumenta em direção ao segmento V (ABE; TAKANO; ITO, 1982;ORSI et al, 1993;CALVO et al, 1999).…”

“…No rato gigante, na cutia e no hamster, o epidídimo apresenta os ductos revestidos por um epitélio colunar simples com estereocílios, e células epiteliais, maiores na cabeça deste órgão, porém a altura do epitélio diminui em direção a cauda, diferente do lúmen e a quantidade de espermatozóides que são menores na cabeça e aumentam em direção da cauda (AMIYA; MAITI, 1982;CALVO et al, 1999;MENEZES, 2001).…”

“…Calvo et al (1999) Segundo Niemi (1965) o ducto deferente do rato, apresenta um epitélio pseudo-estratificado com estereocilios, composto por células altas colunares e células basais aplanadas e uma estreita membrana basal, que separa o epitélio da lâmina própria composta por capilares sanguíneos. O ducto deferente do rato gigante é um tubo reto coberto por tecido fibromuscular denso, revestido por um epitélio pseudo-estratificado colunar com estereocilios, este apresenta pregas que aumentam gradualmente da parte proximal para a parte distal, juntamente com a camada fibromuscular (AMIYA; MAITI, 1982).…”