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Clinical Trial 2003; 24(6): 463-467 PubMed PMID: 15073577 Citation  Keywords:  Adult, Continuous Positive Airway Pressure, Humans, Luteinizing Hormone:blood, Male, Middle Aged, Pituitary Gland:physiology, Sleep Apnea, Obstructive:physiopathology, Testis:physiology, Testosterone:blood, Treatment Outcome,.   

OBJECTIVES: Decreased libido and a decline in morning serum testosterone levels were reported in men with obstructive sleep apnea (OSA). Our study aimed to evaluate the pituitary-gonadal axis in middle age men with OSA before and after treatment with nasal continuous positive airway pressure (CPAP).

MATERIAL AND METHODS: Measurement of the nocturnal serum luteinizing hormone (LH) and testosterone levels and sleep recordings before and after nine months of CPAP treatment in five men with OSA aged 49.5+/-5.2 years. Patients were evaluated during nocturnal sleep at base line and during CPAP treatment. Serum LH and testosterone levels were determined at 20 minutes interval between 1900h and 0700h with concomitant determination of sleep quality, respiration and oxygen saturation.

RESULTS: At base line, patients had higher RDI and PaO2<90%, lower mean and integrated (AUC) values of LH and testosterone. During CPAP treatment, RDI and PaO2<90% were normal. Mean and AUC values of testosterone and LH increased.

CONCLUSIONS: OSA in men is associated with dysfunction of the pituitary-gonadal axis. The central suppression of nocturnal testosterone in these patients is partially corrected during chronic CPAP treatment....

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Journal Article 2003; 24(6): 459-462 PubMed PMID: 15073576 Citation  Keywords:  Agenesis of Corpus Callosum, Animals, Brain Diseases:blood, Corpus Callosum:pathology, Incidence, Male, Mice, Mice, Inbred BALB C, Mice, Mutant Strains, Testosterone:blood, Thyroxine:blood,.   

OBJECTIVES: Approximately 20% of BALB/cCF mice are born with partial or total absence of the corpus callosum. Here, we analyzed testosterone and free thyroxin blood levels in adult male mice of this strain in order to see if these hormones are related to the incidence of callosal defects.

METHODS: Blood collected from the axillary blood vessels of 12 normal and 10 acallosal deeply anesthetized adult male mice was used in order to determine testosterone and free thyroxin levels through chemiluminescence (IMMULITE, Diagnostics Products Corporation, USA).

RESULTS: No significant difference (one-way ANOVA: F = 0.11, df = 1, p > 0.10) was found between normal ((-)X= 1.95, SD = 0.62) and acallosal ((-)X= 1.86, SD = 0.62) mice for free thyroxin level. On the other hand, in those mice that had detectable testosterone levels (above 0.2 ng/ml), a significant difference was found (t = 2.8, df = 6.06, p = 0.03): normal mice (n = 7, (-)X= 8.73, SD = 7.64) had a higher level than acallosal mice (n = 4, (-)X= 0.62, SD = 0.41).

CONCLUSIONS: The present results indicate that the incidence of callosal agenesis is not related to free thyroxin levels in the blood of adult BALB/cCF mice. On the other hand, in spite of the fact that low testosterone levels seems to be frequent in male mice of this strain, acallosal mice tend to have lower levels of this hormone than normal mice....

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Journal Article 2003; 24(6): 431-434 PubMed PMID: 15073570 Citation  Keywords:  Adult, Anorexia Nervosa:metabolism, Appetite:physiology, Diabetes Mellitus:metabolism, Feedback, Physiological, Female, Glucose Tolerance Test, Human Growth Hormone:metabolism, Humans, Hypertension:metabolism, Leptin:blood, Luteinizing Hormone:metabolism,.   

OBJECTIVE: It has been reported that neuropeptides may play a role in the control of appetite and in the mechanism of hormone release. Neuropeptides such as beta-endorphin, neuropeptide Y (NPY), galanin and leptin may affect hormones release, on the other hand the hormonal status may modulate neuropeptide activity.

METHODS: The material consisted of 90 obese women, 30 women with Anorexia Nervosa, and 30 healthy, lean women of control group. Plasma beta-endorphin, NPY, leptin, somatostatin and serum pituitary and gonadal hormones concentrations were measured with RIA methods.

RESULTS: We observed the highest plasma NPY levels in obese hypertensive and diabetic patients. After carbohydrate administration (OGTT) a marked increase of insulin, beta-endorphin and NPY was found. The blunted response of GH to GH-RH may be connected with increased somatostatin activity and hyperinsulinemia. The abnormal response of LH to opioid blockade may be a result of disturbed opioid and NPY activities in obese patients. However in patients with anorexia nervosa, plasma leptin and NPY concentrations were low. The disturbances in beta-endorphin release are also observed.

CONCLUSIONS: The neuroendocrine disturbances in obesity and in anorexia nervosa are opposite. The feedback mechanism between leptin and NPY is disturbed in both in obesity and in anorexia nervosa. An abnormal activity of neuropeptides may lead to disturbed control of appetite and hormonal dysregulation in eating disorders....

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Journal Article 2003; 24(5): 345-347 PubMed PMID: 14647010 Citation  Keywords:  Animals, Antioxidants:pharmacology, Hyperthyroidism:drug therapy, Injections, Intraperitoneal, Male, Melatonin:pharmacology, Rats, Rats, Sprague-Dawley, Testis:drug effects, Testosterone:metabolism, Thyroid Gland:drug effects, Thyroid Hormones:metabolism,.   

OBJECTIVE: Melatonin has a general inhibitory effect on the reproductive system and thyroid functions. Testosterone secretion increases in parallel to thyroid hormones in hyperthyroidism. The aim of this study was to investigate the effects of melatonin application on total T3, T4 and testosterone in hyperthyroid rats.

METHODS: This study was performed on 4 groups each consisted of 6 male Spraque Dawley rats. Control group (G1); sham group (G2); applied 0.5 ml/day of serum physiologic intraperitoneally for 2 weeks, hyperthyroid group (G3); applied 0.3 mg/kg/day thyroxine intraperitoneally for 2 weeks, and hyperthyroid and melatonin supplemented group (G4); applied 0.3 mg/kg/day thyroxine and 3 mg/kg/day melatonin. Blood samples taken by way of decapitation were analysed for total T3, T4 and testosterone by RIA.

RESULTS: Serum total T3 and total testosterone levels were the highest in hyperthyroid group (G3), whereas in hyperthyroid and melatonin supplemented group (G4) were the lowest (P<0.001). Total T4 levels were higher in group 3 than group 1, 2 and 4 (P<0.001).

CONCLUSION: Results revealed that melatonin supplementation in hyperthyroidism suppress secretion of thyroid hormones and testosterone secretion....

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Journal Article 2003; 24(5): 321-324 PubMed PMID: 14647004 Citation  Keywords:  Adult, Coitus, Humans, Klinefelter Syndrome:blood, Male, Sexual Dysfunction, Physiological:blood, Testosterone:blood, Varicocele:blood,.   

OBJECTIVES: The aim of our study is to assess the relationship between serum testosterone levels and the coital activity in groups of married men with Klinefelter's syndrome and in men with a varicocele investigated for marital infertility. These are compared with a group of somatosexually well developed men with a normozoospermia and adequate sexual life.

SUBJECT AND METHODS: The serum testosterone levels were assessed in 77 patients with Klinefelter's syndrome (mean age 31 years, SD 5.78), 58 men with a varicocele (mean age 30.5 years, SD 5.80) and 85 healthy men with normal spermiological values (mean age 32.7 years, SD 6.31). The frequency of sexual intercourse in their marriage was assessed by interview.

RESULTS: We found that, although their serum testosterone levels were significantly lower (p < 0.01), the coital activity in both groups with somatosexual disorders did not significantly differ from the group of men with normal semen parameters. The coital activity in the group of men with Klinefelter's syndrome decreased after 35 years of age, before any decrease in serum male sex hormone levels occurred.

CONCLUSION: Statistical analysis revealed that coital activity did not correlate with testosterone levels, but correlated significantly with age. A possible interpretation of the data is that Mother Nature ensues the survival of species by the production of not only a redundant amount of spermatozoids, but also of male sex hormones....

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Journal Article 2003; 24(3-4): 209-214 PubMed PMID: 14523359 Citation  Keywords:  Animals, Immunohistochemistry, Leydig Cells:physiology, Luminescent Measurements, Male, Organ Size:physiology, Photoperiod, Rats, Rats, Wistar, Seminiferous Tubules:anatomy & histology, Testis:anatomy & histology, Testosterone:blood,.   

OBJECTIVE: The aim of this study was to examine the effects of photoperiod on testes in rat.

DESIGN: For this purpose 21 male Wistar rats were used. Animals were divided into three groups. Control rats in group I were kept under 12 hrs light: 12 hrs dark conditions (12L: 12D) for 10 weeks. Animals in group II were exposed to long photoperiods (18L: 6D), while rats in group III were exposed to short photoperiods (6L: 18D) for 10 weeks. At the end of the experiment, all animals were killed by decapitation and blood samples were obtained. Serum testosterone levels were determined with the use of a chemiluminescent enzyme immunoassay. The testes of all rats were removed and weighed. Testicular tissue was processed semiquantitative evaluation of immunohistochemical testosterone staining. Intensity of immunostaining was determined on a scale between 0 (no staining) and 5 (heavy staining). For morphometric comparison, diameters of seminiferous tubules in each group were measured.

RESULTS: In rats exposed to long photoperiods, testicular weights, diameters of seminiferous tubules and serum testosterone levels were significantly increased as compared to those in control rats. Whereas, exposure of rats to short photoperiods resulted in significantly decrease of testicular weights, diameters of seminiferous tubules and serum testosterone levels as compared to those in control rats and rats maintained in long photoperiods. Immunostaining of testosterone was moderate (3+) in control rats, heavy (5+) in rats exposed to long photoperiods and minimal (1+) in rats exposed to short photoperiods.

CONCLUSIONS: The results of our study indicate that testicular functions increase after exposure to long photoperiods and decrease after exposure to short photoperiods....

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Clinical Trial 2003; 24(3-4): 173-180 PubMed PMID: 14523353 Citation  Keywords:  Adult, Affect:physiology, Female, Humans, Hydrocortisone:metabolism, Male, Music:psychology, Photic Stimulation, Radioimmunoassay, Saliva:metabolism, Sex Characteristics, Stress, Psychological:metabolism, Testosterone:metabolism,.   

OBJECTIVES: The aims of the present study were to examine sex-related differences in testosterone (T) and cortisol (C) changes with music listening and visual stress.

SETTING AND DESIGN: Saliva T and C concentrations were measured in 88 healthy college students (44 males and 44 females). These subjects were placed in one of 4 different conditions: (1) 30 min of listening to music, (2) 30 min of listening to music with visual stress (documentary film without sound including violent scenes), (3) 30 min of visual stress without music, and (4) 30 min of silence.

METHODS: All subjects provided two saliva samples, one collected before intervention and the other after intervention. T and C levels were assessed by radio immuno assay (RIA).

RESULTS: There was a significant difference between the sexes in the way music affected T. Music decreased T in males, whereas it increased T in females. As for C, no sex-related differences were found under any of the conditions studied. C decreased with music and increased under other conditions. THE MAIN FINDINGS: Our data suggests that the effects of music and stress on T differ between males and females.

CONCLUSION: Further investigation is necessary to evaluate the relationships between music and other substances, the effect of degree of preference and hormonal changes not only during music listening but also during music plays and creation....

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Journal Article 2003; 24(3-4): 170-172 PubMed PMID: 14523352 Citation  Keywords:  Animals, Antioxidants:therapeutic use, Male, Malondialdehyde:blood, Melatonin:therapeutic use, Rats, Rats, Sprague-Dawley, Reperfusion Injury:pathology, Spermatic Cord Torsion:pathology, Testicular Diseases:pathology, Testis:metabolism,.   

AIM: Torsion of testis, which is a urologic emergency case, is generally treated by surgical detorsion procedure. However, the resulting reperfusion and both ipsilateral and contralateral testis damage caused thereby are important problems. This study aims at investigating the administration of prophylactic melatonin in order to reduce free radical damage that is caused due to reperfusion after experimental testis torsion-detorsion procedure.

MATERIAL AND METHOD: The rats used in the study were allocated to four groups, each containing 10 rats. Rats in Group I had six hours of torsion (ischemia) followed by orchiectomy. Rats in Group II had six hours of torsion, then received melatonin (10 mg/kg/IM) and after that had detorsion (reperfusion). Rats in Group III had detorsion after six hours of torsion and serum physiologic administration (the same volume as melatonin). Torsion and/or detorsion procedures were not applied in Group IV (control). Ipsilateral, contralateral testis and plasma Malondialdehyde (MDA) levels were determined in all groups.

RESULTS: Tissue and plasma MDA levels in the group which had detorsion were found to be significantly higher than those in the group that had orchiectomy only (p<0.02). Ipsilateral and contralateral testis MDA levels were identified to be significantly lower in the group receiving prophylactic melatonin in comparison to the group receiving serum physiologic (p<0.02). Plasma and contralateral MDA levels correlated positively with MDA levels identified in ipsilateral testis in all groups (rs=+0.89, n=40, p=0.000).

CONCLUSION: In cases where testis torsion is identified, administration of melatonin just before torsion may reduce local and systemic free radical damage....

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