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Journal Article 2006; 27(1-2): 267-270 PubMed PMID: 16648790 Citation  Keywords:  Animals, Dietary Supplements, Injections, Intraperitoneal, Lactic Acid:blood, Male, Rats, Rats, Sprague-Dawley, Swimming:physiology, Testosterone:blood, Zinc:blood,.   

OBJECTIVE: There is fairly scarce information about the effects of zinc, an essential trace element, on performance. Studies concerned with the relation between zinc and exercise mostly concentrate on the distribution of this element in the body in response to exercise. The objective of the present study is to explore how zinc supplementation affects testosterone levels and its relation with lactate in rats subjected to acute swimming exercise.

MATERIALS AND METHODS: Thirty adult male rats of Sprague-Dawley species were equally allocated to 3 groups. Group 1: Control. Group 2: Group subjected to 30-minute acute swimming exercise. Group 3: Group supplemented with intraperitoneal (i.p.) zinc (3 mg/kg day) for 4 weeks and subjected to 30-minute swimming exercise. Blood samples collected from all experimental animals by decapitation method were analyzed to determine free and total testosterone and lactate levels in the plasma.

RESULTS: Group 3 had the highest free and total testosterone levels, followed by Group 1 and Group 2. The highest lactate levels were found in Group 2 and the levels in Group 3 were higher than those in Group 1.

CONCLUSION: Results of the study demonstrate that zinc supplementation leads to a significant increase in testosterone levels and a significant decrease in lactate levels. In conclusion, physiological doses of zinc supplementation can be useful for performance....

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Journal Article 2006; 27(1-2): 247-252 PubMed PMID: 16648789 Citation  Keywords:  Adolescent, Adult, Exercise:physiology, Exercise Test, Humans, Testosterone:blood, Thyroid Hormones:blood, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood, Wrestling:physiology, Zinc:pharmacology,.   

OBJECTIVES: The present study aims to investigate how exhaustion exercise affects thyroid hormones and testosterone levels in elite athletes who are supplemented with oral zinc sulfate for 4 weeks.

METHODS: The study included 10 male wrestlers, who had been licensed wrestlers for at least 6 years. Mean age of the wrestlers who volunteered in the study was 18.70 +/- 2.4 years. All subjects were supplemented with oral zinc sulfate (3 mg/kg/day) for 4 weeks in addition to their normal diet. Thyroid hormone and testosterone levels of all subjects were determined as resting and exhaustion before and after zinc supplementation.

RESULTS: Resting TT3, TT4, FT3, FT4 and TSH levels of subjects were higher than the parameters measured after exhaustion exercise before zinc supplementation (p<0.05). Both resting and exhaustion TT3, TT4 and FT3 values after 4-week zinc supplementation were found significantly higher than both of the parameters (resting and exhaustion) measured before zinc supplementation (p<0.05). Resting total testosterone and free testosterone levels before zinc supplementation were significantly higher than exhaustion levels before zinc supplementation (p<0.05). Both resting and exhaustion total and free testosterone levels following 4-week zinc supplementation were found significantly higher than the levels (both resting and exhaustion) measured before zinc supplementation (p<0.05).

CONCLUSION: Findings of our study demonstrate that exhaustion exercise led to a significant inhibition of both thyroid hormones and testosterone concentrations, but that 4-week zinc supplementation prevented this inhibition in wrestlers. In conclusion, physiological doses of zinc administration may benefit performance....

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Journal Article 2006; 27(1-2): 97-104 PubMed PMID: 16648781 Citation  Keywords:  Animals, Benzhydryl Compounds, Calcium:metabolism, Calcium Channel Blockers:pharmacology, Calcium Signaling:drug effects, Cells, Cultured, Estradiol:analogs & derivatives, Estrogen Antagonists:pharmacology, Estrogens, Non-Steroidal:pharmacology, Excitator.   

OBJECTIVES: Bisphenol A (BPA) is a typical endocrine disrupter. We investigated the mechanisms of rapid Ca(2+) signaling induced by a low dose BPA application in cultured hippocampal neurons.

MATERIALS AND METHODS: The primary culture of hippocampal neurons were prepared from postnatal 3 to 5-day-old rats. Cells were loaded with Calcium Green-1 fluorophore. Ca(2+) imaging and analysis were performed by Argus system.

RESULTS: The application of BPA at 10-100 nM induced a transient increase in the intracellular Ca(2+) of N-methyl-D-aspartate (NMDA)-responsive neurons. The Ca(2+) transient occurred within 30 sec after the BPA application. The proportion of BPA-responsive neurons was 9.6 % and 8.5 % of the total NMDA-responsive neurons, respectively, upon 10 nM and 100 nM BPA application. The pre-treatment of neurons with Ca(2+) channel blockers, thapsigargin and nifedipine, considerably decreased the proportion of BPA-responsive neurons to 0.7 % and 3.7%, respectively. The treatment of neurons with an antagonist of estrogen receptor, ICI 182,780, also significantly decreased the proportion of BPA-responsive neurons down to 1.1 %.

CONCLUSION: These results suggest that a low dose BPA application rapidly drives the Ca(2+) signaling system via activation of non-genomic pathway including estrogen receptors....

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Journal Article 2006; 27(1-2): 214-218 PubMed PMID: 16648776 Citation  Keywords:  Adult, Electrocoagulation, Female, Gonadal Steroid Hormones:blood, Gynecologic Surgical Procedures, Humans, Laparoscopy, Ovulation:physiology, Polycystic Ovary Syndrome:blood, Pregnancy, Pregnancy Rate,.   

OBJECTIVES: To compare the efficacy of ovarian electrocautery performed during microlaparoscopy and laparoscopy, basing on ovulation and pregnancy rates obtained within one year of follow-up.

MATERIALS AND METHODS: Ovarian drillings, performed with the use of endoscopic methods, were carried out in 135 women with hormonal and ultrasound features of PCOS, aged 30-39 (average age 36 +/- 3.3). Laparoscopic ovarian electrocautery was carried out in 65 cases, whereas microlaparoscopic drilling was conducted in 70 cases. The obtained results were compared in regard to duration of the procedure and ovulation/pregnancy rates within one year of follow-up. Changes in hormonal profiles were also compared in both groups, measured in patients who did not get pregnant before, and 3 months after, the procedures.

RESULTS: The difference in durations between the two studied procedures was statistically significant (19 +/- 3 min vs. 24 +/- 4.4 min; p<0.001). However, the ovulation and pregnancy rates did not differ significantly between the two groups (72% vs. 77.7%; p<0.5 and 19.4% vs. 20%; p<0.95, respectively). There were also similar trends in hormonal changes after microlaparoscopic and laparoscopic drilling.

CONCLUSIONS: The efficacy of ovarian drilling in PCOS, estimated by ovulation and pregnancy rates within 12 months of follow-up is similar for microlaparoscopy and laparoscopy, as well as the trends in hormonal changes. Ovarian electrocautery is significantly longer in microlaparoscopy, but the difference in time is of no practical impact....

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Journal Article 2006; 27(1-2): 60-62 PubMed PMID: 16648774 Citation  Keywords:  Adrenocorticotropic Hormone:blood, Animals, Corticosterone:blood, Growth Hormone:blood, Injections, Intraventricular, Male, Nerve Tissue Proteins:pharmacology, Pituitary-Adrenal System:drug effects, Prolactin:blood, Rats, Rats, Inbred WKY,.   

OBJECTIVE: It has been reported that the cocaine and amphetamine regulated transcript (CART) is widely expressed in the hypothalamic nuclei involved in the mechanism of hormonal secretion.

RESEARCH METHODS: In order to evaluate the effect of CART on the activation of the pituitary-adrenal axis in the rat, CART (55-102) in a dose of 0.5 microg in 5 microl CSF was infused into the third ventricle (icv) with an automatic pump. At 10, 30, 60, 120 min after the infusion of CART or vehicle, the animals were decapitated and the trunk blood was collected. Serum ACTH and corticosterone concentrations were measured with RIA kits provided by Phoenix Pharmaceuticals and ICN Biomedicals USA, respectively.

RESULTS: The stimulating effect of CART on ACTH concentration was observed only 30 min after icv injection. However, CART stimulated corticosterone release at 10, 30, 60 min after icv injection.

CONCLUSIONS: CART (55-102) administered intracerebroventricularly (icv) stimulated ACTH and corticosterone release. The stimulating effect of CART on ACTH was short-lived....

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Comparative Study 2005; 26(6): 780-788 PubMed PMID: 16380692 Citation  Keywords:  Age Factors, Animals, Animals, Newborn:physiology, Body Weight:physiology, Corticosterone:blood, Female, Germ Cells:cytology, Hydroxysteroid Dehydrogenases:metabolism, Hypothyroidism:chemically induced, Luteinizing Hormone:blood, Male, Organ Size, Pregnan.   

OBJECTIVE: Effects of transient neonatal hypothyroidism (HPOT) on adult testis size and serum hormone profiles were evaluated in the Charles foster strain of rats, maintained under the temperature of 21 degrees C (HPOTL) or of 34 degrees C (HPOTH).

METHODS: Hypothyroidism was induced in suckling pups in preweanling period (1-21 days), by administering 0.1% 6-propyl-2-thiouracil in drinking water to mothers. Body mass and testis characteristics, the steroidogenic potential [measured by histochemical localization of 3alpha-, 3beta- and 17beta-hydroxysteroid dehydrogenases (HSDHs)] and serum concentrations of thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), luteinizing hormone (LH), testosterone (T) and corticosterone (Cort) were evaluated on the 35th, 45th, 60th and 90th day of age.

RESULTS: The HPOTH rats showed lower testis masses, while the HPOTL rats showed higher testis masses and lower body masses after 90 days. Histologically, the testes of the HPOTH rats demonstrated increased germ cell degeneration after 35 and 45 days and reduced tubular size, germ cell numbers and sperm density after 90 days. In contrast, the testes of the HPOTL rats showed reduced tubular diameters after 35 and 45 days, and increased tubular diameters, germ cell numbers and sperm density after 90 days. Serum TSH, T3, T4, LH and T concentrations and 3beta- and 17beta-HSDH activities were reduced in both groups of the HPOT rats after 35 and 45 days. Intratubular steroidogenesis and a prominent triangle up5 pathway were also found in the HPOT animals.

CONCLUSION: The temperature has a definite influence on the thyroid hormone action, postnatal growth and function of rat testes....

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Journal Article 2005; 26(5): 487-492 PubMed PMID: 16264414 Citation  Keywords:  Aging:metabolism, Antigens, CD:metabolism, Antigens, CD3:metabolism, Antigens, Differentiation, T-Lymphocyte:metabolism, Biomarkers, CD8-Positive T-Lymphocytes, Dehydroepiandrosterone Sulfate:blood, Fatigue Syndrome, Chronic:blood, Female, Humans, Inflamm.   

: There are a few reports that chronic fatigue syndrome (CFS) may be accompanied by changes in hormones, such as dehydroepiandrosterone (DHEA) and insulin-like growth factor (IGF1). This study examines the serum concentrations of DHEA-sulfate (DHEAS), IGF1 and IGF1 binding protein-3 (IGFBP3) in 20 patients with CFS and in 12 normal controls. The IGFBP3/IGF1 ratio was computed as an index for IGF1 availability. We found significantly lower serum DHEAS concentrations in CFS, but no significant differences either in IGF1 or the IGFBP3/IGF1 ratio between CFS patients and normal controls. The decrease in serum DHEAS was highly sensitive and specific for CFS. There were significant and positive correlations between serum DHEAS and serum zinc and the mitogen-induced expression of the CD69 molecule on CD3+CD8+ T cells (an indicator of early T cell activation). There was a significant and negative correlation between serum DHEAS and the increase in the serum alpha-2 protein fraction (an inflammatory marker). Serum IGF1, but not DHEAS, was significantly and inversely correlated to age. The results show that CFS is accompanied by lowered levels of DHEAS and that the latter may play a role in the immune (defect in the early activation of T cells) and the inflammatory pathophysiology of CFS....

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Journal Article 2005; 26(5): 515-520 PubMed PMID: 16264408 Citation  Keywords:  Adrenal Medulla:physiopathology, Adrenocorticotropic Hormone:blood, Animals, Cold Temperature, Corticosterone:blood, Epinephrine:blood, Luminescence, Male, Norepinephrine:blood, Pituitary-Adrenal System:physiopathology, Rats, Rats, Wistar, Restraint, Phys.   

OBJECTIVE: The effects of three different long-term (21 days) stresses: isolation(LTI), forced swimming (LTS) and isolation accompanied by forced swimming (LTI+LTS) on the level of plasma noradrenaline (NA), adrenaline (A), corticosterone (CORT) and adrenocorticotropic hormone (ACTH), both under basal conditions and in response to short-term immobilization and cold as heterotypic additional stressors, were compared.

METHODS: Plasma NA and A were assayed by the radioenzymatic method. Plasma CORT was measured using RIA kits. Plasma ACTH was determined by chemiluminescent method.

RESULTS: LTI produced a significant elevation of basal plasma CORT and ACTH, while basal plasma NA and A concentrations remained unchanged. Combination of long-term isolation and forced swimming, produced a significant elevation of basal plasma ACTH content only, while LTS did not influence the basal level of this hormone. When LTI rats were exposed to immobilization and cold, a significant elevation of plasma NA and A level was recorded. In LTS and LTI+LTS groups of rats exposed to immobilization or cold, increased plasma NA and A levels were observed, but this increase was lower in comparison with that found in LTI rats. No difference in plasma CORT content between the three long-term stressed groups of animals was observed, while plasma ACTH level was significantly more elevated in LTS and LTI+LTS than in LTI rats.

CONCLUSION: Based on these results, it may be concluded that LTI as a psychosocial stress represents a stronger stressor than LTS. Also, daily short-term (15 min, 21 days) swimming stress seems to attenuate the effect of long-term isolation on the activity of sympatho-adrenomedullary system....

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