Effects of photoperiod on structure of lamina propria of the testis of Octodon degus

Abstract

The changes occurring in the testicular lamina propria (LP) of the seasonal breeder Octodon degus were analyzed. Four groups of animals were studied using electron microscopic procedures. The animals in group I were reproductively active, whereas those in groups II, III, and IV were in periods of recrudescence, regression, and resting, respectively. These changes, observed in animals maintained under laboratory lighting conditions, resembled those known to be elicited in feral populations by natural photoperiods. Testicular changes in each group were monitored by calculating the gonadosomatic and spermatogenetic indexes, and by obtaining averages of the diameter of the seminiferous tubules and the height of the seminiferous epithelium. The LP of group I animals consisted of a basal membrane formed by two to four lamellae, inner and outer acellular layers containing moderate numbers of collagenous fibrils, and single or double layers of smoothly contoured myoid cells encircled by a discontinuous lymphatic epithelium. The LP of group IV animals differed considerably from the LP of group I animals: The inner acellular layer was enlarged, and the basal membrane appeared composed of a variable number of lamellae with numerous folds and indentations. Myoid cells were very irregular in contour and enveloped by a well-developed surface coating. The LPs of animals in groups II and III possessed relatively similar characteristics, which appeared to be intermediate between those of groups I and IV. The significance of these morphological changes in the LP are discussed in relation to testicular changes induced by photoperiod and other normal or pathological processes. © 1995 Wiley-Liss, Inc.

Octodon degus: A Diurnal, Social, and Long-lived Rodent

“…a second litter if vegetation does not dry out too quickly (Meserve et al 1995). There is some evidence from field and laboratory data that the male reproductive organs may be at least mildly sensitive to photoperiod changes (Carballada et al 1995;Rojas et al 1995), although no data exist on females. Gestation lasts 90 to 95 days, and lactation lasts 4 to 5 wk (Kleiman et al 1979).…”

Efecto de la Vitamina E en Células Peritubulares de Testículos de Ratones Mus musculus Tratados con Ácido Valproico Durante el Estado Fetal y Pubertad

“…La importancia de este resultado radica en que las alteraciones del peritúbulo pueden alterar funciones testiculares fundamentales asociadas a la fertilidad, sobre todo si se tiene en consideración que las células peritubulares producen efec- tos yuxtacrinos en las células espermatogoniales y efectos paracrinos de regulación del microambiente testicular general a través de proteínas secretadas (Thompson et al, 2018). En este sentido, se ha demostrado que las células peritubulares secretan factores paracrinos que regulan la función de las células sustentaculares (Rojas et al, 1995) y están mediadas por los andrógenos testiculares sintetizados por las células intersticiales (Huhtaniemi & Pelmiemi, 1992) las que, durante la pubertad, son capaces de diferenciarse en respuesta a una mayor producción de andrógenos (Rojas et al, 2017;Thompson, 2018). Nuestros resultados muestran que la VE reduce los efectos deletéreos causados por el VPA administrado durante la gestación, a lo largo del desarrollo testicular, desde etapas fetales, continuando hasta las etapas puberales…”

“…Cabe hacer notar que la distribución y el número de células y fibras que se encuentran en la lámina propia varía dependiendo de la especie. En el caso de especies de roedores, se ha encontrado a continuación de la membrana basal que el peritúbulo consta de dos capas acelulares y dos capas celulares: (1) capa acelular; (2) células mioides o peritubulares; (3) capa acelular y (4) la pared endotelial externa ubicada hacia el intersticio testicular (Rojas et al, 1995). Esto se ilustra esquemáticamente en la figura 1.…”

Interacciones Epitelio-Mesenquimáticas en el Desarrollo Testicular

“…En el roedor Octodon degus la lámina propia presenta dependencia del fotoperiodo (Rojas et al, 1995). Esta dependencia estaría relacionada con el aporte de andrógenos, el cual disminuye durante el período de reposo sexual.…”