Endocrine Abstracts

Research in the field of reproductive biology is largely based on informative mouse models. Almost all of these mouse models (~99%) exhibit an unfavourable reproductive phenotype - these mouse models are subfertile or infertile in one or possibly both sexes. In contrast, the number of animal models that show an enhanced reproductive phenotype is extremely rare. Nevertheless, these mouse models could be very informative in identifying mechanisms and pathways associated with enh...

Introduction: 11β-HSD1 is the key enzyme of intracellular glucocorticoid regulation by converting inactive cortisone to active cortisol. The latter binds to the glucocorticoid and mineralocorticoid receptor (MR) in the heart. Cortisol excess in Cushing’s syndrome leads to left ventricular hypertrophy. Also androgens cause myocardial remodelling. However, the impact of testosterone on the cardiovascular system is strongly disputed showing beneficial and deleterious ef...

Introduction: With the onset of puberty blood pressure increases more in men than in women while boys and girls do not show any gender differences in blood pressure. Androgens are known to play an important role in renal tubular epithelial cell growth, hypertrophy and erythropoetin production and may be important determinants of sex-specific differences in blood pressure. However, the exact mechanisms are not clear yet.Methods: Male Wistar rats aged 8&#1...

Introduction: Androgens are known to play an important role in renal tubular epithelial cell growth, hypertrophy and erythropoetin production, however the exact mechanisms are not clear yet. 5alpha-dihydrotestosterone is synthesized primarily in gonads and skin, and is the most used androgen in studies. However, little is known about testosterone effects in non-gonadal tissues.Methods: Male Wistar rats aged 8–10 weeks were orchiectomized and put on ...

Introduction: With the onset of puberty blood pressure increases more in men than in women while boys and girls do not show any gender differences in blood pressure. Androgens are known to play an important role in renal tubular epithelial cell growth, hypertrophy and erythropoetin production and may be important determinants of sex-specific differences in blood pressure. However the exact mechanisms are not clear yet.Methods: Male Wistar rats aged 8&#15...

Introduction: Androgens are known to play an important role in renal tubular epithelial cell growth, hypertrophy and erythropoetin production, however the exact mechanisms are not clear yet. 5α-dihydrotestosterone is synthesized primarily in gonads and skin, and is the most used androgen in studies. However, little is known about testosterone effects in non-gonadal tissues.Methods: Male Wistar rats aged 8–10 weeks were orchiectomized and put on...

Background: Selenoproteins are involved in oxidative stress defence, cell signalling and hormone metabolism. Accordingly, impairment of selenium (Se) metabolism or transport results in a complex phenotype as exemplified in selenoprotein P knockout mice (SePP-KO). This mouse model is characterized by a disrupted metabolism of Se resulting in neurological and growth defects. Hypothesis: Se impairs regular tissue development by modifying growth signal biosynthesis, anabolic respo...

Background: Selenoproteins are playing an important role in body homeostasis and development. They control thyroid hormone metabolism and are of prime importance for intracellular redox regulation and cellular defence. The SePP knockout mouse (SePP-KO) is a model of impaired Se metabolism characterized by a disrupted distribution system for organified Se. One of the major phenotypes of the homozygote SePP-KO mice is a reduced increase in size and weight during the growth spurt...

Selenium (Se) is indispensable for enzymatic activities of glutathione peroxidases (GPx) involved in antioxidative defense and deiodinase isozymes (Dio) that control thyroid hormone (TH) action. Se deficiency can impact negatively on thyroid galnd funtioning and TH metabolism and thereby perturb development and metabolism. We have generated Se-deficient mice by genetic inactivation of Selenoprotein P (SePP), the main plasma Se carrier. SePP-KO mice display decreased serum and ...

Animal models are valuable tools in fertility research. Worldwide, there are more than 1000 transgenic or knockout mouse models available showing a reproductive phenotype; almost all of them exhibit an infertile or at least subfertile phenotype. By contrast, animal models revealing an improved fertility phenotype are barely described. We developed two outbred mouse models exhibiting a ‘high-fertility’ phenotype. These mouse lines were generated via selection over a t...