Network identification of hormonal regulation

Relations among hormone serum concentrations are complex and depend on various factors, including gender, age, body mass index, diurnal rhythms and secretion stochastics. Therefore, endocrine deviations from healthy homeostasis are not easily detected or understood. A generic method is presented for detecting regulatory relations between...

Bioavailability of tryptophan from a single oral dose of a trytophan-enriched peptide mixture in healthy men

The aim of the study was to investigate the bioavailability of tryptophan (Trp) from a Trp-enriched peptide mixture in healthy men. A second objective was to investigate the effect of this Trp-enriched protein hydrolysate on potential parameters of serotonergic activity. serum serotonim melatonin and prolactin and urinary 5-hydroxyindol-acetic...

Insulin, androgen, and gonadotropin concentrations, body mass index, and waist to hip ratio in the first years after menarche in girls with regular menstrual cycles, irregular menstrual cycles, or oligomenorrhea

Data on changes in hormone concentrations during the first years after menarche are scarce. We studied the relation between gynecological age (age minus age at menarche), hormone concentrations, and body measurements from the 1st to the 6th yr after menarche in 229 observations of girls with regular menstrual cycles, 157 observations of girls...

The bovine protein -lactalbumin increases the plasma ratio of tryptophan to the other large neutral amino acids and in vulnerable subjects raises brain serotonin activity reduces cortisol concentration and improves mood under stress

Background: Increased brain serotonin may improve the ability to cope with stress, whereas a decline in serotonin activity is involved in depressive mood. The uptake of the serotonin precursor, tryptophan, into the brain is dependent on nutrients that influence the cerebral availability of tryptophan via a change in the ratio of plasma...

Endocrine features of polycystic ovary syndrome in a random population sample of 14-16 year old adolescents

Hospital based studies have shown that oligomenorrhoeic adolescents have high luteinizing hormone (LH) and androgen concentrations, endocrine signs of polycystic ovary syndrome (PCOS). The prevalence of these abnormalities in an unselected population of adolescents is not known. We determined LH, follicle stimulating hormone (FSH),...

Magnetic resonance imaging compared with hormonal effects and histopathology of estrogen-induced pituitary lesions in the rat

Estrogen-induced pituitary lesions in rats were studied in time-sequence experiments using magnetic resonance imaging (MRI), hormone determinations and light microscopy. The main purpose of the study was to evaluate the usefulness of MRI in comparison with conventional biochemical and histopathological methods for detecting the pituitary lesions...

Type A behaviour, borderline hyperventilation and psychological, psychosomatic and neuroendocrine responses to mental task load

Psychological, psychosomatic and neuroendocrine (in blood) responses to mental task load were investigated in relation to type A behaviour and borderline hyperventilation. For this purpose 32 apparently healthy, male volunteers were classified on the basis of their scores on the Jenkins Activity Survey (JAS) and on a questionnaire assessing...

Effect of work load on free and sulfate-conjugated plasma catecholamines, prolactin, and cortisol

The effects of maximal performance capacity and different work load intensities on the response of free and sulfate-conjugated plasma catecholamines, prolactin (PRL), and cortisol were studied in six healthy male volunteers. In a first experiment, the volunteers had to perform a step-wise incremental bicycle ergometer test to determine the onset...