Testicular expression of NGF, TrkA and p75 during seasonal spermatogenesis of the wild ground squirrel (Citellus dauricus Brandt)

Abstract

The nerve growth factor (NGF) not only has an essential effect on the nervous system, but also plays an important role in a variety of non-neuronal systems, such as the reproductive system. The aim of this study was to compare the quality and quantity in expression of NGF and its receptors (TrkA and p75) in testes of the wild ground squirrel during the breeding and nonbreeding seasons. Immunolocalization for NGF was detected mainly in Leydig cells and Sertoli cells in testes of the breeding and nonbreeding seasons. The immunoreactivity of TrkA was highest in the elongated spermatids, whereas p75 in spermatogonia and spermatocytes in testes of the breeding season. In the nonbreeding season testes, TrkA showed positive immunostainings in Leydig cells, spermatogonia and primary spermatocytes, while p75 showed positive signals in spermatogonia and primary spermatocytes. Consistent with the immunohistochemical results, the mean mRNA and protein level of NGF and TrkA were higher in the testes of the breeding season than in non-breeding season, and then decreased to a relatively low level in the nonbreeding season. In addition, the concentration of plasma gonadotropins and testosterone were assayed by radioimmunoassay (RIA), and the results showed a significant difference between the breeding and nonbreeding seasons with higher concentrations in breeding season. In conclusion, these results of this study provide the first evidence on the potential involvement of NGF and its receptor, TrkA and p75 in the seasonal spermatogenesis and testicular function change of the wild ground squirrel.

Can the Genetic Origin Affect Rabbit Seminal Plasma Protein Profile along the Year?

“…Besides, this also accords with Zhang et al. () findings in wild ground squirrels, which showed that the production of NGF in testes was decreased during the non‐breeding season and increased in the breeding season.…”

“…This result is in agreement with Schneidgenov a et al (2011) findings that showed less sperm motility and concentration during winter season. Besides, this also accords with Zhang et al (2015) findings in wild ground squirrels, which showed that the production of NGF in testes was decreased during the non-breeding season and increased in the breeding season.…”

Seasonal expressions of androgen receptor, estrogen receptors and cytochrome P450 aromatase in the uteri of the wild Daurian ground squirrels (Spermophilus dauricus)

“… 32 , 33 Size and weight of reproductive organs were generally related to their reproductive ability. 34 The seasonality of uterine mass shown in the present study was in agreement with extensive reports in this species, 8 , 27 and the present histological results showed that the uterine gland grew bigger, including nucleus growth and gland lumen extension in the breeding season, and the gland lumen shrunk remarkably and less nuclei were observed in the non-breeding season. These findings were similar to those observations in other seasonal breeders, such as possums and dunnarts.…”

Histochemistry today: Detection and location of single molecules

“…Several papers were aimed at illustrating the tissue organization and protein expression of still poorly described organs from various Vertebrate and Invertebrate species: [42][43][44][45][46][47][48][49][50][51][52][53][54] here, the morphological description of the microanatomical and histological features was paralleled by the detection of specific molecules responsible for the tissue functional characteristics, also as a consequence of seasonal dynamic changes. [55][56][57] The immunolabeling of marker proteins was extensively applied in studies aimed at distinguishing stem/progenitor cells or at elucidating the process of cell differentiation and morphogenesis during pre-and post-natal development in mammals, including humans, [58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76] with special attention to the nervous system, 65,66 sensory organs, [67][68][69] skin, 70 lung, 70,71 and the skeletal apparatus. [72][73][74][75] Also in plants, the histochemical d...…”