Phenotypic change in response to variation in environmental cues has been widely documented in fish. Transitions in social dominance, in particular, have been shown to induce a rapid switch in reproductive phenotypes in many species. However, this effect has been mainly studied in adults and focused on behavioural transitions. The way social cues constraint the phenotypic development of juvenil...

BACKGROUND Testicular volumes obtained with orchidometers or external linear measurements in the scrotum (centimeter ruler or calipers) grossly over-estimate ultrasound volumes, have much variability and may not be accurate or reproducible. The reference of the values obtained by orchidometers or US, to age or Tanner stages is not useful to determine the normal values for stages of puberty, bec...

OBJECTIVE To measure testicular volume and the gonadotrophin response to gonadotrophin-releasing hormone (GnRH) stimulation in adolescents undergoing left varicocelectomy. PATIENTS AND METHODS Thirteen adolescents undergoing varicocelectomy had their testicular volume and endocrine function evaluated before and after surgery. RESULTS The initial left testicular volume was consistently small...

Background: Human beings are unavoidably exposed to ambient electromagnetic fields (EMF) generated from various electrical devices and from power transmission lines. The effects of extremely low-frequency electromagnetic fields (ELF-EMF) on the biological functions of living organisms represent an emerging area of interest for human health. One of the critical issues is that EMF may adversely a...

Testicular descent is an essential part of normal male sexual development. Any anomaly that disrupts normal testicular descent will be clinically evident as cryptorchidism. Several factors, such as Hoxa-10, epidermal growth factor (EGF), calcitonin gene-related peptide (CGRP), and hormones, especially androgens and insulin-like factor 3 (INSL-3), have been suggested as being regulators of testi...

conclusions the inhibition of mini-puberty period in male rats was demonstrated to have an effect on their testicular function to some extent. results serum t and lh levels peaked at two hours after birth, while fsh peaked at hour 0, and bilateral testicular weight peaked at four hours after birth. the rats that underwent ether inhalation five minutes after birth had markedly reduced serum horm...

This review will focus the roles of TNF-alpha, IL-1 alpha, and IL-1 beta in the mammalian testis and in two testicular pathologies, testicular torsion and orchitis. TNF alpha in the testis is produced by round spermatids, pachytene spermatocytes, and testicular macrophages. The type 1 TNF receptor has been found on Sertoli and Leydig cells and numerous studies suggest a paracrine mode of action...

The common marmoset (Callithrix jacchus) is a New World primate that exhibits a man-like adult testicular organization. Aims: this study examines the pubertal testicular development in the common marmoset. Material and methods: immature male common marmosets (n= 48) were monitored longitudinally for a period of 13 months. Body weight and testicular volume (TV) were recorded, and testosterone le...

In the present study, we examined the cellular origin and the expression levels of interleukin-18 binding protein (IL-18 BP), during normal maturation of murine testis. Immunohistochemical staining of testicular tissues from sexually mature mice, shows that testicular germ cells, at different stages of differentiation, express IL-18 BP. Leydig cells/interstitial cells and peritubular cells expr...

In the last decades, studies in rodents have highlighted links between in utero and/or neonatal exposures to molecules that alter endocrine functions and the development of genital tract abnormalities, such as cryptorchidism, hypospadias, and impaired spermatogenesis. Most of these molecules, called endocrine disrupters exert estrogenic and/or antiandrogenic activities. These data led to the hy...