CONTEXT Little is known about the association of low endogenous testosterone levels and abnormal sleep patterns in older men, although pharmacological doses of testosterone are associated with increased severity of sleep apnea and other sleep disturbances. OBJECTIVE The objective of the study was to examine the association between serum testosterone levels with objectively measured sleep char...

BACKGROUND The secretion of thyroxin (T4) as the main hormone of thyroid gland is regulated by androgens. The present study aimed to evaluate the effect of testosterone and finasteride administration and castration on serum levels of T4 and to show the effect of this regulation on total body weight, weight of testis, and the weight of prostate. METHODS Male adult rats (n = 32) were divided in...

The paucity of pharmacokinetic data on testosterone gel formulations and absence of such data on estradiol administration in healthy young men constitutes a fundamental gap of knowledge in behavioral endocrinological research. We addressed this issue in a double-blind and placebo controlled study in which we applied a topical gel containing either 150mg of testosterone (N=10), 2mg of estradiol ...

OBJECTIVE To study the endogenous sex hormone levels in natural postmenopausal women and their association with the presence of internal carotid artery (ICA) atherosclerosis. DESIGN Case-control study METHODS We compared 56 patients with severe ICA atherosclerosis referred for carotid artery endarterectomy (CEA) with 56 age-matched control subjects free of severe atherosclerotic disease. Th...

BACKGROUND Obesity is associated with both impaired testosterone production and a chronic state of low grade inflammation. Previously it was believed that this inflammation was mediated by a decline in the immunosuppressive action of testosterone. However, more recently an alternative hypothesis (GELDING theory) has suggested that inflammation originating from the passage of intestinal bacteria...

BACKGROUND: Measurements of hormonal concentrations by immunoassays using fluorescent tracer substance (Eu3+) are susceptible to the action of chemical agents that may cause alterations in its original structure. Our goal was to verify the effect of two types of anticoagulants in the hormone assays performed by fluorometric (FIA) or immunofluorometric (IFMA) methods. METHODS: Blood samples were...

Aging men develop a significant loss of muscle strength that occurs in conjunction with a decline in serum testosterone concentrations. We investigated the effects of testosterone administration to six healthy men [67 +/- 2 (SE) yr] on skeletal muscle protein synthesis, strength, and the intramuscular insulin-like growth factor I (IGF-I) system. Elderly men with serum testosterone concentration...

Background: The secretion of thyroxine (T4) as the main hormone of thyroid gland is regulated by androgens. The present study aimed to evaluate the effect of testosterone and finasteride administration and castration on serum levels of T4 and to show the effect of this regulation on total body weight, weight of testis, and the weight of prostate. Methods: Male adult rats (n = 32) were divided i...

OBJECTIVE To investigate the effect of metformin on testosterone levels in men with type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODS Seventy newly diagnosed drug-naive T2DM and HbA1c >9.0% (75 mmol/mol) were treated intensive insulin pump therapy for 5 days to achieve glucose normalization. They randomized control (continued only) (plus metformin) groups (1:1) 1 month. Testos...

AIM There is a need to elucidate the variables associated with testosterone suppression among men on daily opioid therapy for chronic pain. OBJECTIVE The objective of this study was to examine several variables related to opioid use including daily dose, duration of action (long acting vs. short acting), and specific opioid to ascertain specific influences on total serum testosterone levels i...