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Journal Article 2006; 27(1-2): 114-120 PubMed PMID: 16648815 Citation  Keywords:  Adrenocorticotropic Hormone:blood, Adult, Estradiol:blood, Female, Follicular Phase:metabolism, Humans, Hydrocortisone:blood, Luteinizing Hormone:blood, Menstrual Cycle:metabolism, Progesterone:blood,.   

OBJECTIVES: A strong positive coupling has been already documented between the adrenocortical axis and the gonadal axis at the time of the initiation of the preovulatory LH surge of the menstrual cycle in the human. The LH preovulatory surge starts in the morning at the time of the acrophase (maximal plasma cortisol values) of the cortisol circadian rhythm. Also, it was shown that morning maximal plasma cortisol values were higher during the follicular phase than during the luteal phase. The objective of the present study was designed to determine the exact day of the fall of morning maximal plasma cortisol values and the functional correlates which could exist between plasma 17beta-Estradiol, LH, ACTH and Cortisol at the time of the preovulatory LH surge.r />r /> METHODS: We performed a detailed analysis of variations of plasma ACTH and cortisol concentrations during the various phases of the LH surge: 1) the day before the ascending phase, 2) the day of the ascending phase, 3) the day of the LH peak, 4) the day of the descending phase, 5) the day after the descending phase. 17beta-Estradiol, LH and FSH were determined by microparticle enzyme immunoassays kits and Progesterone determination was made using a radioimmunoassay kit. ACTH determination was made using a RIA kit and Cortisol was assayed by a RIA method.r />r /> RESULTS: Plasma ACTH concentrations were at their highest the day before the day of the ascending phase of the LH surge and significantly higher than the day of the descending phase and the day after the day of the descending phase (p < 0.02). Plasma cortisol concentrations were at their highest, with almost similar values, the day before the day of the ascending phase, the day of the ascending phase and the day of the LH peak; then, plasma cortisol concentrations were significantly lower than those of the preceding days, the day of the descending phase (p = 0.0001) and the day after the day of the descending phase (p = 0.02), when plasma 17beta-Estradiol starts to decrease.r />r /> CONCLUSION: Overall, these results suggest that the positive ACTH-Cortisol-Estrogen dependency, well documented in the female rat, is also operating at midcycle during the menstrual cycle in the human....

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Journal Article 2006; 27(1-2): 133-136 PubMed PMID: 16648814 Citation  Keywords:  Adult, Aged, Aging:metabolism, Amino Acids:metabolism, Amyotrophic Lateral Sclerosis:metabolism, Cytosol:metabolism, Female, Humans, Male, Middle Aged, Mitochondrial Myopathies:metabolism, Muscle, Skeletal:growth & development, Myositis:metabolism, Neurom.   

: Sarcopenia describes the involuntary decline in muscle mass with aging, coupled with fatigue, and loss of force and function. We investigated 113 human muscle biopsy specimens obtained from patients with neuromuscular diseases and controls. We measured 21 amino acids in these muscle biopsies. Age emerged as a significant negative predictor of cytosolic concentration ratio of glutamine to total branched chain amino acids and of glutamine to total aromatic amino acids using stepwise multiple linear regression analysis. This pattern of alteration corresponds well to documented alterations in skeletal muscle of critically ill patients and after immobilization. Additionally, in myositis, citrulline was significantly elevated, while glutamate, lysine and taurine were significantly reduced. Furthermore, in sporadic amyotrophic lateral sclerosis (sALS) the total aromatic amino acids, arginine, glutamate, threonine, and tyrosine were significantly elevated. This study provides evidence, that alteration of glutamine is correlated to aging and might reflect increased proteolysis in aged and diseased human skeletal muscle....

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Journal Article 2006; 27(1-2): 73-80 PubMed PMID: 16648813 Citation  Keywords:  Adolescent, Aging:metabolism, Child, Electromagnetic Fields:adverse effects, Female, Humans, Male, Melatonin:urine, Sex Characteristics, Television,.   

OBJECTIVES: Changes in magnetic field are associated with a decrease in nocturnal urinary melatonin excretion. Television screens emit low and very low frequency electromagnetic waves (radiofrequencies and light) and exposure to them may be associated with a decrease in 24-hour melatonin in children's urine. Design and setting. An observational study in schools of Cavriglia, Italy, determined melatonin in 24-hour urines from 42 boys and 32 girls 6 to 13 years of age after one week of watching TV and after another week of abstaining from watching TV.r />r /> RESULTS AND MAIN FINDINGS: In a gender- and age-dependent fashion, exposure to a television screen was associated with lower urinary melatonin concentrations, affecting particularly younger children at a pubertal stage when important changes in melatonin's time structure occur.r />r /> CONCLUSION: Additional work should test further relations to growth, maturation and development, focusing on any adverse effect from exposure to a television screen also on obesity from a neuro-hormonal viewpoint, quite apart from any decreased activity and/or other lifestyle alterations associated with watching TV....

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Journal Article 2006; 27(1-2): 157-161 PubMed PMID: 16648812 Citation  Keywords:  Animals, Cattle, Craniocerebral Trauma:metabolism, Female, Hemorrhage:metabolism, Hypothalamus:metabolism, Immunohistochemistry, Male, Radioimmunoassay, Rest:physiology, Sex Characteristics, Stress, Psychological:metabolism, Vasopressins:blood,.   

OBJECTIVES: This study investigates antidiuretic hormone (ADH) plasma concentration in bulls and heifers at rest, after transportation stress, trauma and massive hyper-acute hemorrhage at slaughter, with special attention to differences between sexes. We also quantified ADH concentration in the ADH-producing hypothalamic area.r />r /> SETTING AND DESIGN: The study was carried out on animals at the abattoir, exploiting the routinely procedure of slaughtering to obtain the experimental stressful conditions. The control group was represented by a group of animals matched for breed, age and gender.r />r /> RESULTS: ADH plasma values suggest that transportation stress has little or no effect in heifers in contrast to bulls. In both sexes ADH release increases after open head trauma due to stunning prior to slaughter. Hemorrhagic hyper-acute stress caused by bleeding induces a rapid hundredfold rise of ADH plasma concentration that becomes diergic (physiologically different between sexes), with males showing far higher values. Females show a higher ADH concentration in the hypothalamus.r />r /> MAIN FINDING: This study points out a difference in ADH output between bulls and heifers under conditions of severe hemorrhagic stress, as produced by severing of the neck vessels at slaughtering.r />r /> CONCLUSION: Extreme stress unmasks endocrine differences in bovine ADH release that may be relevant only during specific circumstances, such as fighting....

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Journal Article 2006; 27(1-2): 281-287 PubMed PMID: 16648811 Citation  Keywords:  Analgesics, Animals, Antidepressive Agents, Second-Generation:pharmacology, Blood Glucose:metabolism, Diabetes Complications:drug therapy, Diabetes Mellitus, Experimental:blood, Female, Fluoxetine:pharmacology, Hyperalgesia:drug therapy, Male, Mice, Mice,.   

OBJECTIVES: Clinical and experimental trials have demonstrated that some of selective serotonin reuptake inhibitors (SSRIs) have some suspicious effects on blood glucose levels in different directions. Especially fluoxetine and sertraline are studied in this point of view. These drugs are also used in treatment of depression and peripheral neuropathy in diabetic patients. Paroxetine and fluoxetine, members of this drug group, besides having antidepressant effects were shown to have antinociceptive effects in animals and humans. They can be used in the treatment of chronic pain as an adjuvant drug or alone. But less is known about their actions on pain in case of diabetes. The aim of this study is to investigate the antinociceptive effects of fluoxetine and paroxetine in diabetic and non-diabetic mice while monitoring their effects on blood glucose levels.r />r /> METHODS: Mice of either sex were randomly used in experiments. The antinociceptive effects of paroxetine and fluoxetine were evaluated using hot plate test both in diabetic and non-diabetic mice. The effects of these drugs on blood glucose levels were also evaluated in another group of mice both in diabetic and non-diabetic mice.r />r /> RESULTS: Fluoxetine and paroxetine showed significant antinociceptive effect at all doses and at all times tested in non-diabetic mice, but they could not successfully show this effect in diabetic mice. They also had controversial effects on blood glucose levels.r />r /> CONCLUSION: Although they showed increasing or decreasing effects on blood glucose levels in non-diabetic and diabetic mice, they showed antinociception on hot-plate test showing dissociation between blood glucose levels and analgesia....

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Journal Article 2006; 27(1-2): 219-224 PubMed PMID: 16648810 Citation  Keywords:  3-Hydroxysteroid Dehydrogenases:genetics, Adrenal Cortex Hormones:metabolism, Alleles, Child, China:epidemiology, Female, Gene Frequency, Genotype, Gonadal Steroid Hormones:blood, Humans, Insulin Receptor Substrate Proteins, Molecular Sequence Data, Phosp.   

OBJECTIVES: In order to investigate whether the variances in the candidate genes (Insulin receptor substrate IRS-1, beta3-adrenergic receptor ADRB3, 3 beta-hydro-xysteroid dehydrogenase HSD3B2, glucocorticoid receptor GRL and 21-hydroxylase CYP21) which affect the metabolism of adrenal steroids hormone and body composition, are associated with precocious puberty in Chinese girls.r />r /> METHODS: PCR-RFLP analysis method was applied in the typing of six activity SNPs in five genes in two groups: 176 precocious puberty girls as case and 192 healthy girls as control.r />r /> RESULTS: The typing results showed that the frequencies of the allele CYP21 L282 polymorphism were 32.7% and 32.6% in case and control groups (P=0.518), respectively. For IRS-1 R972, they were 0.6% in cases and 2.3% in controls (P=0.043), for ADRB3 R64, 13.6% in cases and 12% in controls (P=0. 378), and for GRL S363, 7.4% in cases and 5.73% in controls (P=0.335). No sample in the two groups carries the variation of CYP21 I172N and HSD3B2 L236S.r />r /> CONCLUSION: Among these six activity SNPs in five candidate genes, IRS-1 972R was statistically associated with the onset time of puberty in Chinese girls. In order to confirm whether the candidate genes have any other activity SNPs that are associated with the onset time of puberty in Chinese girls, resequencing of these candidate genes is needed in following time....

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Case Reports 2006; 27(1-2): 93-96 PubMed PMID: 16648809 Citation  Keywords:  Adenoma:metabolism, Adrenocorticotropic Hormone:blood, Cell Proliferation, Human Growth Hormone:blood, Humans, Hydrocortisone:blood, Immunohistochemistry, Insulin-Like Growth Factor I:metabolism, Male, Microscopy, Electron, Middle Aged, Pituitary Hormones.   

: Herein, we report the case of a 46-year-old male patient with only one month of double vision. Radiological examination revealed a pituitary tumor. Endocrinological investigations showed no pathological alterations of anterior pituitary function. Neuropathological examinations revealed a pituitary gland adenoma with an elevated proliferation rate (MIB-1 index 4-5 %) as well as an elevated p53 expression leading to the diagnosis of an atypical pituitary adenoma. Interestingly, the tumor exhibited strong basophilia in routine histology and densely secretory granules in electron microscopy (EM). However, no hormone excess was detectable in immunohistochemistry. In contrast to clinical and immunohistochemical observations, EM and routine histology findings implied a hormone production. This discrepancy might be due to a production of unfunctional pre-stages of pituitary gland proteins in this fast growing neoplasm....

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Journal Article 2006; 27(1-2): 257-259 PubMed PMID: 16648808 Citation  Keywords:  Animals, Bombesin:pharmacology, Estradiol:pharmacology, Estrogens:pharmacology, Female, Injections, Intraventricular, Luteinizing Hormone:antagonists & inhibitors, Ovariectomy, Rats, Rats, Inbred WKY,.   

OBJECTIVE: Bombesin, 14-amino acid peptide, discovered in the gastrointestinal tract, is widely distributed in the central nervous system (CNS). The specific receptors of bombesin in the pituitary have been characterized. Bombesin plays an important role in the gastric and pancreatic secretion, in the mechanism of food intake, thermoregulation and in pituitary hormone secretion. There are contentious opinions about the effect of bombesin on hormone secretion.r />r /> THE AIM: The aim of this study was to evaluate the effect of estrogens in the modulation of bombesin action on LH release.r />r /> RESEARCH METHODS: Female Wistar-Kyoto rats, two weeks after ovariectomy (OVX), were implanted with a cannula being located in the third cerebroventricle. Thereafter, the rats were primed with 17beta estradiol in a dose of 25microg/0.2ml s.c. for three consecutive days. On the day of the experiment, bombesin at a concentration of 0.5 microg in 5microl vehicle (artificial cerebrospinal fluid) or equal volume of the vehicle was infused into the third ventricle with an automatic pump. At 60 or 120 min after the infusion the animals were decapitated, and the trunk blood was collected. Rat serum LH was measured by RIA kit supplied by Dr A.F. Parlow from NIDDK Baltimore, MD.r />r /> RESULTS: Bombesin inhibited LH release at 120 min and it did not change LH release at 60 min after icv administration.r />r /> CONCLUSIONS: The response of LH release after central injection of bombesin is modified by estrogens....

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