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Comparative Study 2005; 26(6): 806-810 PubMed PMID: 16380687 Citation  Keywords:  Animals, Glutathione:metabolism, Hyperthyroidism:chemically induced, Kidney:metabolism, Lipid Peroxidation, Male, Malondialdehyde:metabolism, Melatonin:metabolism, Oxidative Stress:physiology, Rats, Rats, Sprague-Dawley, Testis:metabolism, Thyroxine,.   

OBJECTIVE: The present study aimed at determining how 3-week intraperitoneal melatonin administration affected oxidative stress caused by experimental hyperthyroidism.

MATERIALS AND METHODS: The study was conducted on 30 male rats of Sprague-Dawley species. The experimental animals were divided to 3 groups (control, hyperthyroidism and hyperthyroidism+melatonin). The supplementation was continued for 3 weeks after which the animals were sacrificed and tissue malondyaldehyde (MDA) and glutathione (GSH) levels were determined.

RESULTS: MDA levels in kidney and testis tissues in hyperthyroidism group were higher than those in control and hyperthyroidism+melatonin administered groups (p<0.001) and levels in hyperthyroidism+melatonin administered group were higher than those in the control group (p<0.001). The highest GSH levels were obtained in hyperthyroidism+melatonin-administered group (p<0.001) and GSH levels in hyperthyroidism group were higher than those in the control group (p<0.001).

CONCLUSION: Results of the study demonstrate that hyperthyroidism induced by 3-week L-thyroxine administration increased oxidative stress in kidney and testis tissues and that although melatonin administration inhibited this stress to a certain extent, it could not bring the stress down to the level in controls....

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Comparative Study 2005; 26(6): 729-732 PubMed PMID: 16380686 Citation  Keywords:  Age Factors, Animals, Animals, Newborn, Longitudinal Studies, Male, Organ Size:drug effects, Rats, Rats, Sprague-Dawley, Selective Estrogen Receptor Modulators:pharmacology, Sexual Behavior, Animal:drug effects, Tamoxifen:pharmacology, Testis:cytology, Te.   

OBJECTIVE: In this study we examined the possibility that demasculinization produced by the neonatal administration of tamoxifen is accompanied by a decline in plasma levels of testosterone during adulthood.

METHODS: Wistar male rats received either a treatment with 12.5 microg/kg of tamoxifen during the first eight days of age or a treatment with 100 microg/kg of tamoxifen for five days. Each treatment had their respective control group. During adulthood their masculine sexual behavior was analyzed. At 8 months of age, males were killed by decapitation, trunk blood was collected and peripheral glands were dissected and weighed. Testosterone levels were measured by HPLC. Histological analysis of peripheral glands was performed.

RESULTS: Both neonatal tamoxifen treatments significantly decreased male sexual behavior when compared to control values. In addition, both treatments also showed a significant decrease in testicular weight when compared to control groups, as well as a decrease in seminal vesicle weight. In the microscopic analysis, a significant decrease in the diameter of the seminiferous tubules was observed, especially in the animals treated with 100 microg/kg of tamoxifen. However, no differences were observed between tamoxifen treated and control animals concerning plasma levels of testosterone.

CONCLUSION: The present results indicate that behavioral manifestations and changes in peripheral reproductive organs that accompanied demasculinization are not due to a deficit in testosterone secretion....

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Clinical Trial 2005; 26(5): 447-452 PubMed PMID: 16264418 Citation  Keywords:  Adolescent, Aging:physiology, Body Height:drug effects, Child, Female, Growth Hormone:therapeutic use, Hormones:blood, Human Growth Hormone:deficiency, Humans, Magnetic Resonance Imaging, Male, Pituitary Gland:anatomy & histology, Predictive Value of Test.   

INTRODUCTION: Certain relationships between pituitary size and growth hormone (GH) secretion have previously been observed, however they are still a matter of controversy. Organic abnormalities of the hypothalamic-hypophyseal region are important for predicting growth response to GH therapy.

AIM: Evaluation of relations between GH secretion and the pituitary size in short children and estimation of the efficacy of GH therapy in children with GH deficiency (GHD).

PATIENTS AND METHODS: The analysis comprised 216 short children (159 boys). Two GH stimulation tests, as well as magnetic resonance image (MRI) examination, were performed in each patient. All the patients with GHD were treated with GH for, at least, one year.

RESULTS: Significant correlations were found between pituitary height and GH secretion (p < 0.05). Patients were classified into three (3) groups: 1) pituitary hypoplasia (HP) for height age; 2) HP for the chronological age but not for the height age; 3) normal pituitary size. Significant differences in GH secretion were observed among the groups (6.1+/-5.3 vs. 8.1+/-4.4 vs. 12.3+/-9.1 ng/mL, respectively). There was a negative correlation between GH peak and height gain during GH therapy (r = -0.34). The highest growth improvement was noticed in patients with HP for the height age.

CONCLUSIONS: Pituitary hypoplasia for the height age is related to more severe GH deficiency and the best response to GH therapy....

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Journal Article 2005; 26(5): 480-486 PubMed PMID: 16264415 Citation  Keywords:  Adult, Antibodies, Protozoan:analysis, Blood Donors:psychology, Enzyme-Linked Immunosorbent Assay, Exploratory Behavior:physiology, Female, Humans, Male, Personality Tests, Reward, Toxoplasmosis:immunology,.   

OBJECTIVES: Toxoplasma gondii, a parasitic protozoan, infects about 30 - 60% of people worldwide. Toxoplasma is known to induce behavioral changes and an increase of dopamine in mice. The presence of anti-Toxoplasma antibodies (latent toxoplasmosis) is also a risk factor for schizophrenia. Latent toxoplasmosis in men (male soldiers) is associated with lower novelty seeking. As the novelty seeking is supposed to negatively correlate with level of dopamine, the observed effect was interpreted as indirect evidence of increased dopamine levels in subjects with toxoplasmosis. However, it is also possible that the observed effect was caused by association of both novelty seeking and Toxoplasma infection with a third factor, e.g. size of place of residence.

METHODS: Personality profile of 290 blood donors (205 men and 85 women) were measured by Cloninger's TCI (Temperament and Character Inventory) and their blood samples were assayed for the presence of anti-Toxoplasma antibodies. Difference between Toxoplasma-infected and Toxoplasma-free subjects was tested with ANCOVA method with gender, size of place of residence, and age as covariates.

RESULTS: The present analysis revealed that lower novelty seeking was associated with latent toxoplasmosis both in men and women. The effect of infection on novelty seeking remained significant even after adjustment for size of place of residence (p<0.01).

CONCLUSION: Decreased novelty seeking in Toxoplasma-infected subjects have been already confirmed in three independent populations (male soldiers and male and female blood donors). These findings suggest that the local inflammation-induced increase in dopamine in the brain of infected subjects can represent a missing link between toxoplasmosis and schizophrenia....

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Journal Article 2005; 26(5): 536-540 PubMed PMID: 16264404 Citation  Keywords:  Animals, Antithyroid Agents, Cholesterol:blood, Folic Acid:blood, Homocysteine:blood, Hyperthyroidism:blood, Hypothyroidism:blood, Lipids:blood, Male, Propylthiouracil, Rats, Rats, Wistar, Thyroid Function Tests, Thyroxine, Vitamin B 12:blood,.   

INTRODUCTION: It is claimed in a limited number of studies carried out on human beings that plasma homocysteine levels increased in hypothyroid patients and decreased in hyperthyroid patients.

OBJECTIVE: The aim of this study is to determine total plasma homocysteine, thyroid function tests, vitamin B12, folic acid and lipid levels and to explore the relations among them in rat models with induced hypothyroidism and hyperthyroidism with a view to investigating whether hypothyroid and hyperthyroid rat models could represent human hypothyroidism and hyperthyroidism models.

MATERIAL AND METHOD: The study included 30 male Wistar Albino species rats with a mean weight of 200 - 250 g. Rats were randomly divided into 3 groups as 1) hypothyroid group, 2) hyperthyroid group and 3) control group. Hypothyroidism was induced by adding 10 mg/kg/day propylthiouracil to rats' drinking water for 30 days. In order to induce hyperthyroidism, rats were administered 10 microg/100 g L-thyroxin ampule via intraperitoneal route for 10 days.

RESULTS: We found that total plasma homocysteine level of the hypothyroid group was significantly lower than those of the control group (p<0.05) and the hyperthyroid group (p<0.001). Total plasma homocysteine level of the hypothyroid group was found insignificantly higher than that of the control group (p>0.05) and significantly higher than that of the hyperthyroid group (p<0.001). We established a significant and positive correlation between total plasma homocysteine level and thyroid hormone levels. We did not identify a significant relation between total plasma homocysteine level and serum folic acid and serum vitamin B12 levels.

CONCLUSION: Our findings are different from the findings reported in human hypothyroidism and hyperthyroidism studies. We believe that hypothyroid and hyperthyroid rat models cannot represent human hypothyroidism and hyperthyroidism models....

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Journal Article 2005; 26(5): 548-554 PubMed PMID: 16264402 Citation  Keywords:  Animals, Body Weight:drug effects, Follicle Stimulating Hormone:blood, Leptin:blood, Luteinizing Hormone:blood, Male, Orchiectomy, Rats, Rats, Sprague-Dawley, Testosterone:blood, Zinc:blood,.   

AIM: The aim of this study was to investigate how zinc-deficiency and testosterone supplementation, both in combination and individually, affect plasma LH, FSH and leptin levels in castrated rats.

DESIGN: Group 1, Control Group. Group 2, Castration Group. Group 3, Testosterone Group. Group 4, Zinc-deficient Group. Group 5, Testosterone, Zinc-deficient Group. Group 6, Zinc-deficient, Castration Group. Group 7, Testosterone, Castration Group. Group 8, Zinc-deficient, Testosterone, Castration Group.

MEASUREMENTS: Plasma zinc, leptin, LH, FSH, free and total testosterone levels were measured.

RESULTS: Group 2 had the highest levels of leptin and LH, besides having the highest FSH levels together with Group 6 (p<0.01). Groups 5 and 8 had the lowest leptin levels (p<0.01). Leptin levels in Groups 4 and 7 were higher than those in Groups 5 and 8, but lower than those in all other groups (p<0.01). LH levels in Group 4 were not different than those in Groups 3, 5 and 8, but significantly lower than those in all other groups (p<0.01). Free and total testosterone levels were higher in Group 4 than in castration groups that were not supplemented testosterone, but were lower in the former than in all others (p<0.01).

CONCLUSION: Plasma LH may be more effective than testosterone on plasma leptin and zinc can be an important mediator of the effect LH exercises on leptin....

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Journal Article 2005; 26(4): 347-350 PubMed PMID: 16136011 Citation  Keywords:  Adrenocorticotropic Hormone:blood, Adult, Follicle Stimulating Hormone:blood, Humans, Hydrocortisone:blood, Infertility, Male:blood, Leydig Cells:metabolism, Luteinizing Hormone:blood, Male, Sperm Count, Stress, Psychological:blood, Testosterone:biosynthe.   

INTRODUCTION: Emotional stress connected with work or, for example, depressive reaction to infertility, is one of frequent causes of decreased quality of semen. An objective examination of this factor is difficult because stress depends also on patient's emotionality. One of the ways to study this problem is evaluating the relation between ACTH level and selected semen parameters.

MATERIAL AND METHODS: The study was based on results of the examination of 83 men from couples treated for infertility in the Gynecology and Infertility Clinic of the Jagiellonian University in Krakow. Determination of ACTH, FSH, LH, cortisol, testosterone and androstendion was performed using ELISA.

RESULTS: Lower average values of semen volume, sperm cells concentration and A sperm cell mobility and higher value of D sperm cells mobility were identified in the group of men from couples treated for infertility with ACTH level >30 pg/ml in comparison to the WHO standards and the control group with ACTH <30 pg/ml. Higher ACTH and cortisol levels were detected in the group of men with the sperm count <10 mln/mL in comparison to the control group with the sperm count >20 mln/mL. Low and statistically insignificant correlation was observed between androstendion and testosterone levels, what might suggest the reduction of testosterone synthesis in this group.

CONCLUSIONS: Our results might indicate that the rise of ACTH and cortisol inhibit the conversion of adrostendion into testosterone in Leydig-cells resulting in the rise of androstendion, drop of testosterone production and lower average values of semen volume, sperm cells concentration and A sperm cell mobility and higher value of D sperm cells mobility....

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Journal Article 2005; 26(4): 355-360 PubMed PMID: 16136009 Citation  Keywords:  Adaptation, Psychological, Adult, Aggression:physiology, Female, Hostility, Humans, Male, Middle Aged, Personality:physiology, Reference Values, Stress, Psychological:blood, Testosterone:blood,.   

OBJECTIVES: Many studies assessing the role of sex hormones, like testosterone, on stress and hostility factors have been primarily conducted in selected atypical populations such as violent criminals as well as androgen users and abusers. Therefore, the main aim of the current study was to investigate the association between testosterone levels and two psychosocial variables: stress and hostility in a cohort of healthy individuals who were members of a health maintenance organization (HMO).

METHODS: At five quarterly visits, psychosocial scales and blood draws were collected. Psychological stress was measured by using several scales that assessed different types of stress, including daily hassles, major life events and perceived stress. Similarly, different aspects of hostility were measured, among them cynicism, hostile affect and aggressive responding. Plasma collected from each visit was used for testosterone level determinations.

RESULTS: Testosterone levels were significantly associated with stress in both males and females. However, whereas this association exhibited a "threshold effect" in males, it demonstrated a direct and continuous linear relationship between these variables in females. Hostility was not correlated with testosterone levels in neither males nor females.

CONCLUSIONS: These results suggest that testosterone levels in normal males and females may be more reflective of an intricate balance between physiological responding and emotional coping to stressors than the hostility profile of the individual....

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