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Biography 2002; 23(Suppl 4): 8-9 PubMed PMID: 12496728 Citation  Keywords:  Awards and Prizes, Behavioral Research:history, History, 20th Century, History, 21st Century, Neuroendocrinology:history,.   

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Biography 2002; 23(Suppl 4): 6-115 PubMed PMID: 12496727 Citation  Keywords:  Awards and Prizes, Behavioral Research, Czech Republic, History, 20th Century, History, 21st Century, Humans, Neuroendocrinology:history,.   

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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(5-6): 452-454 PubMed PMID: 12500171 Citation  Keywords:  Administration, Intranasal, Animals, Capillaries:drug effects, Food Deprivation, Male, Oligopeptides:administration & dosage, Photoperiod, Pineal Gland:blood supply, Proto-Oncogene Proteins c-fos:biosynthesis, Rats, Rats, Wistar, Stress, Physiological:phy.   

OBJECTIVES: The content of C-Fos protein was tested in rat pinealocytes in the norm and stress and in case of intranasal administration of Epitalon (Ala-Glu-Asp-Gly), which regulated pineal secretion processes, presumably, via protooncogenes.

SETTING: Intact and osmotic-stress-exposed rats were used for the immunohistochemical detection of C-Fos protein. All animals were intranasally administered with Epitalon, the last infusion made in two hours before the biopsy. Simultaneously, light microscopy of the pineal parenchyma was performed in all groups of animals.

RESULTS: A slight but significant C-Fos increase was observed only in stress-exposed pinealocytes of rats after intranasal Epitalon infusions. C-Fos was irregularly distributed throughout pineal cells. In stress, the clusters of 5 10 cells containing C-Fos in their cytoplasm were detected. The dilation of capillaries and pericapillary space induced by an osmotic stress was partially reduced by the intranasal infusions of Epitalon.

CONCLUSIONS: Tetrapeptide Epitalon is synthesised on the basis of the amino acid composition of pineal peptide extract Epithalamin. Epitalon modulates pineal secretion only under a stress impact but never in the norm. It prevents osmotic-stress-induced pathologic changes in the pineal parenchyma structure. Besides, the physiological activity of Epitalon seems to be mediated by the activation of protooncogenes in pinealocytes....

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Journal Article 2002; 23(5-6): 447-451 PubMed PMID: 12500170 Citation  Keywords:  Animals, Cell Differentiation:physiology, Gene Expression Regulation:physiology, Humans, Immune System:physiology, Neuroendocrine Tumors:metabolism, Neuronal Plasticity:physiology, Neuropeptides:metabolism, Neurosecretory Systems:cytology,.   

: The term neuroendocrine has been used to define cells that secrete their products in a regulated manner, in response to a specific stimulus. The neuroendocrine system includes neurons and endocrine cells sharing a common phenotypic program characterized by the expression of markers such as neuropeptides, chromogranins, neuropeptide processing enzymes SPC2 and SPC3 (subtilase-like pro-protein convertases) or dense core secretory granules. Various theories such as the APUD (amine precursor uptake decarboxylation) concept, the diffuse neuroendocrine system (DNES) or the paraneuron concept have been put forth to classify neuroendocrine cells as a cohesive group. Neuroendocrine characteristics have been used as evidence of a common embryological origin for normal and neoplastic cells. However, it is now recognized that neuroendocrine characteristics can be observed in various cell types, such as immunocytes, that are not of a common embryological origin with either neurons or endocrine cells. We propose to redefine previous "neuroendocrine" concepts to include the notion that activation of specific genetic switches can lead to the expression of a partial or full neuroendocrine phenotype in a variety of cell types, including immune cells....

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Journal Article 2002; 23(5-6): 443-446 PubMed PMID: 12500169 Citation  Keywords:  Animals, Cell Nucleus:ultrastructure, Cell Size:physiology, Cricetinae, Endoplasmic Reticulum, Rough:ultrastructure, Female, Ganglionectomy, Glycogen, Golgi Apparatus:ultrastructure, Lysosomes:ultrastructure, Mitochondria:ultrastructure, Organelles:ultras.   

OBJECTIVES: Superior cervical ganglia are of crucial importance in regulating the secretion of the pineal hormone melatonin. Changes in pineal morphology have been observed in many mammalian species after sympathectomy. Therefore, we decided to investigate the ultrastructure of Djungarian hamster pinealocytes following superior cervical ganglionectomy.

MATERIAL AND METHODS: Eight adult female Djungarian hamsters (Phodopus sungorus) were used in this study. The superior cervical ganglia were removed bilaterally in four animals, whereas the other four animals served as sham-operated controls. The pineal glands were removed four weeks after the operation and processed for electron microscopic study. The cross-sectional areas of pinealocyte and its nucleus, and relative volume of mitochondria, Golgi apparatus, lysosomes, granular endoplasmic reticulum, and glycogen particles as well as the numbers of dense-core vesicles and "synaptic" ribbons were estimated using a digital analyzer connected on-line to IBM-PC computer. Statistical analysis of the data was performed using Student's t test and Snedecor F test.

RESULTS: Significant reduction in the cross-sectional areas of the pinealocyte and its nucleus as well as in the relative volumes of mitochondria and glycogen particles was observed after superior cervical ganglionectomy in comparison with sham-operated controls. Sympathectomy resulted also in reduction of the number of dense-core vesicles. On the contrary 2,5 fold increase in the number of "synaptic" ribbons was observed in ganglionectomized animals in comparison to sham-operated controls.

CONCLUSION: Deprivation of sympathetic innervation leads in Djungarian hamsters not only to suppression of melatonin synthesis and secretions but, as appears from our studies, induces also morphological changes suggesting lower metabolic and secretory activity of pinealocytes....

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Clinical Trial 2002; 23(5-6): 440-441 PubMed PMID: 12500167 Citation  Keywords:  Adult, Brain:diagnostic imaging, Female, Graves Disease:metabolism, Humans, Ligands, Male, Middle Aged, Receptors, Somatostatin:biosynthesis, Sample Size, Sex Factors, Somatostatin:analogs & derivatives, Tomography, Emission-Computed, Single-Photon,.   

: Animal experiments and observations in human brains have convincingly shown that sexual differentiation not only concerns the genitalia but also the brain. This has been investigated also in the light of a possible explanation of a presumed biological aetiology of transsexuality. The volume of the central subdivision of the bed nucleus of the stria terminalis, a brain area that is essential for sexual behaviour, has been reported to be larger in men than in women. Additionally, the number of somatostatin expressing neurons in this region was shown to be higher in men than in women. As neuronal production of somatostatin is involved the idea is striking whether somatostatin-receptor density in the cortex of cerebral hemispheres might be related to gender identity. We investigated in vivo the density of somatostatin-receptors in selected regions of the human brain in both sexes by means of receptor scintigraphy. Basal ganglia tracer uptake of 111-In-Pentreotide was equally low in both genders at 0,80% +/ 0,26 (related to tracer uptake of the whole brain layer). Temporal cortex accumulated at 2,9% +/ 1,1 in men and at 2,3% +/ 0,76 in women. Frontal brain region had an uptake of 3,0% +/ 1,4 in male and of 2,5% +/ 1,3 in female. This shows a tendency in males for relatively augmented uptake indicating higher somatostatin receptor density in temporal and frontal cerebral cortex....

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Journal Article 2002; 23(5-6): 437-439 PubMed PMID: 12500166 Citation  Keywords:  Animals, Diabetes Mellitus, Experimental:chemically induced, Disease Models, Animal, Insulin:pharmacology, Insulin-Like Growth Factor I:analysis, Male, Rats, Rats, Sprague-Dawley, Sulfonylurea Compounds:pharmacology,.   

OBJECTIVE: Diabetes Mellitus is associated with decreased insulin-like growth factor-I (IGF-I) levels and also, poor growth in diabetes is related with low circulating levels of IGF-I. Insulin acts via an increase of IGF-I synthesis on growth. We studied the effects of insulin and sulphonylureas on serum IGF-I levels and aimed to evaluate the restoration of IGF-I in different therapeutic strategies.

DESIGN AND SETTING: Thirty male rats were used in the study and diabetes was induced by a single intraperitoneal injection of streptozotocin (35 mg/kg body weight). After confirmation of hyperglycemia, rats were divided into three groups. The first group was treated with insulin, and second group with glimepiride, third group was not treated (control group). IGF-I levels were measured at basal, after streptozotocin and at the end of the treatment period.

RESULTS: Serum IGF-I levels were found to decrease from 577.2 ng/ml to 253.0 ng/ml after streptozotocin (p<0.005). After 1 month, IGF-1 levels were found 524.0 ng/ml in insulin group, 449.3 ng/ml in sulphonylurea group, and 313.1 ng/ml in control group. The increase in IGF-I was statistically significant in insulin group (p<0.005), and in sulphonylurea group (p<0.05), but it was not significant in control group (p>0.05).

CONCLUSIONS: Serum IGF-I levels decrease in diabetes and insulin treatment restores IGF-I depletion significantly. And although less effective, treatment with glimepiride restores IGF-I levels significantly....

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