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Clinical Trial 2002; 23(5-6): 455-458 PubMed PMID: 12500172 Citation  Keywords:  Adult, Auditory Threshold, Delayed-Action Preparations:administration & dosage, Estradiol:administration & dosage, Female, Follicle Stimulating Hormone:blood, Follow-Up Studies, Hearing Loss:diagnosis, Hearing Tests, Hormone Replacement Therapy, Humans, M.   

BACKGROUND: Estrogens have not only direct and beneficial effect on relaxation of the arteries increasing the blood flow in the blood vessels, but also their level of secretion has considerable effect on synthesis of acetylcholine a neurotransmitter indispensable for appropriate functioning of the hearing organ. The aim of this study is analysis of the effect of hormones on the hearing organ in women who underwent surgical castration.

MATERIAL: The study included 40 females, aged between 32 55 years who had undergone an operative treatment mainly because of uterine myoma. A group of 50 women aged between 32 50 years with appropriate hormone level comprised the control group.

METHOD: Each woman investigated underwent the following examinations: gynaecological, otolaryngological and laboratory tests, such as: evaluation of levels of estradiol (E) and folliculin stimulating hormone (FSH). The assessment of hearing was carried out using tone and speech audiometry, tympanometry, test registration of auditory brain stem responses (ABR) and otoacoustic emissions (EOAE). The examinations mentioned above are performed in women as initial examinations before surgical treatment and as follow-up examinations 1, 3 and 12 months after the surgery.

RESULTS: The results presented in this paper include initial examinations and follow-ups 3 months after the surgical treatment taking into consideration the correlation with the results of laboratory tests and the results obtained in the control group....

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Journal Article 2002; 23(2): 149-154 PubMed PMID: 12011801 Citation  Keywords:  Animals, Cells, Cultured, Enzyme Inhibitors:pharmacology, Female, Follicle Stimulating Hormone:blood, Leptin:pharmacology, Luteinizing Hormone:blood, Neuropeptide Y:pharmacology, Nitric Oxide:metabolism, Pituitary Gland:cytology, Rats, Rats, Inbred WKY, o.   

OBJECTIVES: The aim of this study was to investigate the influence of NMMA on the mechanism of leptin and NPY action in in vivo and in vitro on pituitary hormone release by female rats in diestrus.

METHODS: In vivo experiments based on four-day ip injections of: 1) murine recombinant leptin (mrLep); 2) human NPY; 3) saline; 4) NMMA (50 microg) was applied prior to administration of mrLep; 5) NMMA (50 microg) was applied prior to administration of NPY; 6) NMMA (50 microg); 7) NMMA (350 microg) was applied prior to administration of mrLep; 8) NMMA (350 microg). The blood samples for LH and FSH were collected after decapitation of animals on the fifth day of study. In vitro experiments studied the effects of these peptides on LH release from pituitary cell culture.

RESULTS: In vivo: Leptin+ NMMA (50 microg) stimulated LH. NPY+ NMMA (50 microg) increased LH. NMMA (350 microg) stimulated FSH release. In vitro: The stimulatory effect of leptin on LH release in vitro was observed after 120 min of incubation, but after 60 mins of incubation the inhibitory effect of leptin on LH release was increased by NMMA. Leptin +NMMA (vs NMMA) decreased LH release with highest statistical significance. NPY 10 nM 60 min after incubation decreased LH release. There was no effect of NMMA on LH release.

CONCLUSION: In vivo results show, that NO probably mediates in leptin action on LH release. Moreover, effects of leptin on LH release from cultured pituitary cells are dependent on time of incubation. NPY decreased LH release in vitro....

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Journal Article 2001; 22(5): 332-336 PubMed PMID: 11600882 Citation  Keywords:  17-alpha-Hydroxyprogesterone:blood, Adolescent, Adrenal Hyperplasia, Congenital, Adrenocorticotropic Hormone, Adult, Dehydroepiandrosterone Sulfate:blood, Estradiol:blood, Fasting, Female, Follicle Stimulating Hormone:blood, Follicular Phase, Humans, Hype.   

OBJECTIVES: To determine melatonin production in hyperandrogenic women.

MATERIAL AND METHODS: Seventeen women with late onset adrenal hyperplasia due to 21-hydroxylase deficiency (LOCAH) and 15 control women were studied in early follicular phase of the menstrual cycle. Fasting serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E(2)), testosterone, dihydroepiandrosterone sulfate (DHEA-S), 17-hydroxyprogesterone (17-OHP) as well as the peak 17-OHP response to ACTH (250 microg IV) and 24h urinary 6-sulfatoxymelatonin (aMT6s) were determined in all participants.

RESULTS: All 17 hyperandrogenic women were carrying mutations of the CYP21 gene. Women with LOCAH had significantly higher serum testosterone, DHEA-S, 17-OHP and ACTH stimulated 17-OHP values compared with controls. Their aMT6s values (44.6+/-20.3 microg/24h) were significantly higher than the values in control women (31.5+/-20.3) (p<0.03). The urinary aMT6s values were positively correlated with testosterone (p<0.04), DHEA-S (p<0.02) and peak 17-OHP (p<0.04).

CONCLUSIONS: Women with LOCAH have increased melatonin production. There is a relationship between adrenal androgens and melatonin in these women....

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Journal Article 2001; 22(5): 349-355 PubMed PMID: 11600877 Citation  Keywords:  Animals, Appetite Regulation:drug effects, Energy Metabolism:drug effects, Estradiol:blood, Female, Follicle Stimulating Hormone:blood, Galanin:blood, Hormones:blood, Leptin:analysis, Luteinizing Hormone:blood, Neuropeptide Y:blood, Neuropeptides:blood, P.   

OBJECTIVES: Some hormonal disturbances were demonstrated in starvation. Leptin, NPY and galanin play an important role in the control of appetite and in the mechanism of hormone release.

METHODS: In order to evaluate the effect of starvation on the relationship between leptin, neuropeptide Y (NPY) galanin and pituitary and gonadal hormones release, plasma leptin, NPY and galanin as well as serum LH, FSH, prolactin (PRL), estradiol, progesterone levels in non-starved female rats (in diestrus) and after 72 hrs of starvation were measured with RIA methods. Effects of leptin, NPY and galanin administration on pituitary and gonadal hormones were investigated in vivo and in vitro experiments.

RESULTS: Plasma leptin, NPY and galanin as well as serum estradiol and progesterone concentrations were significantly lower in starved rats as compared with non-starved rats. However serum prolactin level was significantly higher in starved rats. Opposite effects after leptin and NPY administration on hormone release in vivo and in vitro experiments were observed in non-starved rats. However, in starved rats we did not find changes in pituitary and gonadal hormones release after leptin, NPY and galanin injection or the hormonal response was blunted.

CONCLUSIONS: 1) The disturbances in neuropeptides activity and in hormones release were observed in starvation. 2) Leptin, NPY and galanin have direct and indirect effects on pituitary and gonadal hormones release. 3) In starvation the hormonal response to leptin, NPY and galanin is impaired....

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