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Journal Article 2002; 23(4): 321-324 PubMed PMID: 12195234 Citation  Keywords:  Adjuvants, Immunologic:pharmacology, Animals, Carcinogenicity Tests, Dehydroepiandrosterone:pharmacology, Estradiol:pharmacology, Female, Galanin:genetics, Gene Expression:drug effects, Pituitary Gland, Anterior:drug effects, Prolactin:blood, RNA, Messeng.   

OBJECTIVES: The effects of dehydroepiandrosterone (DHEA) on galanin (GAL) and prolactin (PRL) mRNA expression in the anterior pituitary of Fischer 344 rats were studied, taking in consideration that: (1) DHEA is an androgen with estrogenic activity on pituitary lactotrophs; (2) estrogens induce prolactinomas in Fischer 344 rats; and (3) GAL has been considered the main mediator of estrogen-induced lactotroph proliferation.

DESIGN: Female rats were ovariectomized and used as controls or treated during 2 weeks with DHEA (500 mg/kg/day or 5 mg/kg/day or 50 mg/kg/day) or estradiol (E2, 50 microg/kg/day), as a positive control for pituitary growth and GAL induction. GAL and PRL mRNA expression were studied by in situ hybridization.

RESULTS: Both DHEA and E2 induced PRL mRNA synthesis. However, DHEA neither produced pituitary enlargement nor GAL induction, in contrast to E2.

CONCLUSIONS: Our results shows that GAL is not involved in the estrogenic activity of DHEA on pituitary lactotrophs, and suggest that DHEA effects are exerted directly on the PRL gene or through another mechanism(s) not related to GAL....

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Clinical Trial 2002; 23(4): 303-308 PubMed PMID: 12195231 Citation  Keywords:  Arsenic:analysis, Autistic Disorder:complications, Child, Child, Preschool, Female, Fursultiamin:administration & dosage, Hair:chemistry, Humans, Lead:analysis, Male, Pilot Projects, Severity of Illness Index, Thiamine Deficiency:complications,.   

OBJECTIVES: In a Pilot Study, the clinical and biochemical effects of thiamine tetrahydrofurfuryl disulfide (TTFD) on autistic spectrum children were investigated.

SUBJECTS AND METHODS: Ten children were studied. Diagnosis was confirmed through the use of form E2, a computer assessed symptom score. For practical reasons, TTFD was administered twice daily for two months in the form of rectal suppositories, each containing 50 mg of TTFD. Symptomatic responses were determined through the use of the computer assessed Autism Treatment Evaluation Checklist (ATEC) forms. The erythrocyte transketolase (TKA) and thiamine pyrophosphate effect (TPPE), were measured at outset and on completion of the study to document intracellular thiamine deficiency. Urines from patients were examined at outset, after 30 days and after 60 days of treatment and the concentrations of SH-reactive metals, total protein, sulfate, sulfite, thiosulfate and thiocyanate were determined. The concentrations of metals in hair were also determined.

RESULTS: At the beginning of the study thiamine deficiency was observed in 3 out of the 10 patients. Out of 10 patients, 6 had initial urine samples containing arsenic in greater concentration than healthy controls. Traces of mercury were seen in urines from all of these autistic children. Following administration of TTFD an increase in cadmium was seen in 2 children and in lead in one child. Nickel was increased in the urine of one patient during treatment. Sulfur metabolites in urine did not differ from those measured in healthy children.

CONCLUSIONS: Thiamine tetrahydrofurfuryl disulfide appears to have a beneficial clinical effect on some autistic children, since 8 of the 10 children improved clinically. We obtained evidence of an association of this increasingly occurring disease with presence of urinary SH-reactive metals, arsenic in particular....

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Journal Article 2002; 23(4): 281-285 PubMed PMID: 12195225 Citation  Keywords:  Anti-Inflammatory Agents, Non-Steroidal:adverse effects, Aspirin:adverse effects, Asthma:chemically induced, Humans, Neurosecretory Systems:pathology,.   

: Available clinical data on aspirin-sensitive asthma (ASA) indicate that ASA patients have certain disturbances in the nervous, endocrine, immune and other body systems. It has been found that such patients have a lower melatonin (MT) production in daytime, a pathology of the platelet membrane-receptor complex, and a pathological response to exogenic MT and acetylsalicylic acid. A hypothesis has been suggested in which ASA is considered as apudopathy caused by dysfunction of MT-producing cells. The decreased MT production and the disturbed cell sensitivity to MT lead to pathological changes in individual organs and functional systems. As a result, there is an enhanced lipid peroxidation, an excessive production of reactive oxygen radicals, and a reduced inhibitory action of MT on the 5-lipoxygenase and NO-synthase activities. The lower MT content also results in an intense aggregation of platelets, activating these cells and increasing the production of leukotrienes and nitric oxide. These changes disturb the pulmonary microcirculation, causing the bronchial obturation syndrome even in patient who do not take aspirin or other nonsteroidal anti-inflammatory drugs. The lower basic production of MT is also responsible for a lower content of its metabolite-endogenic acetylsalicylic acid, thereby increasing the sensitivity of melatonin-producing cells, in particular of platelets, to this acid. So, even minimal aspirin doses inhibit the activity of COX-1, which shunts the already abnormal metabolism of arachidonic acid. This, in turn, leads to a greater production of leukotrienes and, hence, to a severe course of the disease. This hypothesis has become the basis for a new pathogenetic approach to the treatment of ASA patients by correcting the melatonin content with peptide bioregulators--the epiphysis extracts--Epithalamin and Epiphamin....

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Journal Article 2002; 23(4): 273-280 PubMed PMID: 12195224 Citation  Keywords:  Animals, Humans, Pituitary Gland, Posterior:physiology, Receptors, Purinergic:physiology,.   

: The neurohypophysis is an original model of the CNS secretory system releasing vasopressin (AVP) and oxytocin (OXT), two neuropeptides hormones synthesized by the magnocellular neurons of the hypothalamus. Specific patterns of action potentials originating from cellular bodies of magnocellular neurons control the release of AVP and OT, but intra-neurohypophysis regulations do modulate the neuropeptides release. There is now good evidence for the effects of extracellular purines in the control of neurohypophysial secretion. This paper brings together evidence for the multiple, intricate actions of purines in the extracellular space of the neurohypophysis. It covers four main points. First, the activity-dependent release of endogenous ATP in the neurohypophysis. Second, the action of ATP on both neuronal and non-neuronal compartments of the neural lobe. Third, the termination of ATP positive feedback by ecto-nucleotidases. And finally the possible involvement of adenosine in the regulation of neurohypophysial secretion and glial plasticity. The data suggest that ATP and adenosine are physiological modulators of the release of neurohypophysial peptides by acting directly on nerve terminals and indirectly on neurohypophysial astrocytes. Since purinergic receptors are widespread in nervous and endocrine systems, the neurohypophysis appears as an useful model for studying the role of purines in the regulation of stimulus-secretion coupling and neuron-glia interactions. The feedback mechanisms found in the neurohypophysis could be ubiquitous, occurring throughout the central nervous system and in other secretory systems....

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Editorial 2002; 23(4): 271-272 PubMed PMID: 12195223 Citation  Keywords:  Humans, Neuroendocrinology:trends, Periodicals as Topic:trends,.   

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Congresses 2002; 23(Suppl 2): 84-87 PubMed PMID: 12163855 Citation  Keywords:  Animals, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

: The International Symposium "Light, Endocrine Systems and Cancer" was held on May 2-3 at Cologne University, Germany. The symposium was organized by Professor Claus Piekarski and Dr. Thomas C. Erren, Institute and Polyclinic for Occupational and Social Medicine. The main goal of the symposium was to evaluate the epidemiological and experimental data on the effect of the exposure to light-at-night on cancer risk and to indicate the main directions of future research in the field. The symposium covered also the mechanisms and epidemiology of skin cancer which, however, are not included in the present summary....

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Editorial 2002; 23(Suppl 2): 82-83 PubMed PMID: 12163854 Citation  Keywords:  Circadian Rhythm:physiology, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

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Editorial 2002; 23(Suppl 2): 79-81 PubMed PMID: 12163853 Citation  Keywords:  Animals, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

: A conference was held at the University of Cologne on May 2-3, 2002, to discuss the strength-of-the-evidence supporting a linkage between light, endocrine systems and cancer. This overview of the conference is intended to summarize some of the key elements of the conference and to indicate both conclusions and research gaps identified by this reviewer....

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