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Editorial 2005; 26(3): 173-174 PubMed PMID: 15990718 Citation  Keywords:  Humans, Love, Neurosecretory Systems:physiology, Stress, Psychological:physiopathology,.   

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Editorial 2005; 26(3): 167-171 PubMed PMID: 15990717 Citation  Keywords:  Data Interpretation, Statistical, Neuroendocrinology, Statistics as Topic:methods,.   

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Clinical Trial 2005; 26(2): 143-147 PubMed PMID: 15855886 Citation  Keywords:  Adult, Cerebral Cortex:physiology, Diabetes Complications:physiopathology, Diabetes Mellitus, Type 2:complications, Diabetic Neuropathies:diagnosis, Evoked Potentials, Motor:physiology, Evoked Potentials, Somatosensory:physiology, Humans, Middle Aged, Neu.   

OBJECTIVES: Diabetic neuropathy and autonomic nervous system neuropathy are recognized as the most common clinical pictures of nervous system disorders caused by diabetes mellitus (DM). Damage to the brain and the spinal cord is rare. The aim of this work is to show the importance of somatosensory and motor evoked potentials (SEP and MEP) for the early diagnosis of nervous system damage related to diabetes mellitus.

MATERIAL AND METHODS: We examined spinal and cortical somatosensory evoked potentials (SEP) after median and fibular nerve stimulation in diabetics and control subjects. We measured the latencies of individual wave deflections and peripheral and central conduction time (PCT and CCT) of spinal and cortical SEP. Similarly, transcranial magnetic stimulation was used for measuring the central and peripheral conduction time (CCT and PCT) in a group of type 1 diabetics and a control group of volunteers.

RESULTS: The examination SEP and MEP proved and confirmed the prolongation not only of peripheral conduction time, but also of the central conduction time - especially in spinal cord structures. An assumption that spinal cord changes are connected with the decreased number of myelinated fibers able to conduct the impulses from periphery and brain cortex, respectively, has to be accepted.

CONCLUSIONS: The results suggest that the use of somatosensory and motor evoked potentials (SEP and MEP) examination and conduction times measurement has significance in the confirmation of unapparent lesions of the spinal cord in diabetics of both types....

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Clinical Trial 2005; 26(2): 136-142 PubMed PMID: 15855885 Citation  Keywords:  Adult, Aged, Alcohol Drinking:urine, Body Mass Index, Circadian Rhythm:physiology, Electromagnetic Fields, Female, Humans, Lymphoma:urine, Male, Melatonin:analogs & derivatives, Middle Aged, Reference Values, Statistics, Nonparametric,.   

OBJECTIVES: Exposure to extremely low frequency electromagnetic fields (ELF-EMF) has been suggested to suppress melatonin secretion, which might result in higher cancer risks because of its missing oncostatic action. We investigated the effects of residential exposure to ELF-EMF on the excretion of urinary 6-sulfatoxymelatonin (6-OHMS), the major melatonin metabolite, as an indicator of nocturnal melatonin secretion.

METHODS: 6-OHMS was measured in two spot urine samples, collected at 22.00 h and 08.00 h, in 29 men and 22 women. Spot ELF-EMF measurements were conducted at the centre and the four angles of the living room, the bedroom, and the kitchen of study subjects at low current configuration (all lights and appliances turned off), and they were repeated immediately at high current configuration (all lights and appliances turned on).

RESULTS: Risk of a reduced 6-OMHS nocturnal secretion was elevated for daily alcohol intake (OR = 6.4; 95%C.I. 1.4,33.1), and body mass index (BMI) above the median (OR = 2.2; 95%C.I. 0.5,9.6). Risk of disrupted rhythm of 6-OHMS excretion was moderately elevated for domestic ELF-EMF exposure above the upper tertile at low current configuration (OR = 2.6; 95%C.I. 0.4,15.7).

CONCLUSION: Alcohol consumption, BMI, and gender seem to affect nocturnal melatonin secretion, while an effect of residential exposure to ELF-EMF is uncertain. Future studies should properly account for the effect of such variables, when addressing the hypothesis of disturbances in melatonin secretion as a plausible explanation for the reported excess risk of several tumoral diseases associated with low level ELF-EMF exposure....

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Clinical Trial 2005; 26(2): 131-135 PubMed PMID: 15855884 Citation  Keywords:  Adolescent, Adult, Autoantibodies:analysis, Drug Combinations, Estradiol:therapeutic use, Estriol:therapeutic use, Female, Germ Cells:immunology, Hormone Replacement Therapy, Humans, Medroxyprogesterone Acetate:therapeutic use, Menstruation Disturbances:c.   

INTRODUCTION: To investigate levels of antiovarian autoantibodies in girls and young women with disturbances of menstrual cycle before and during treatment with hormonal therapy. To explain morphological changes in ovarian structure in these patients.

MATERIAL AND METHODS: Studied group included 39 patients. 18 patients were treated for primary amenorrhoea, 21 for menstrual cycle disorders. Patients included in the study were repeatedly examined at the beginning of the study and after six months during which they were treated by estrogen and gestagen. In all patients we have tested FSH, LH and FSH/LH ratio, presence of antiovarian antibodies. Results were compared with those obtained in control women. 21 antiovarian antibodies positive patients were indicated for laparoscopic biopsy. Bioptic sample was examined using light and electron microscopy.

RESULTS: Our treatment with hormonal therapy lead to the reduction of ovarian antigens. In 85% of the cases marked decrease of antiovarian autoantibodies levels was observed, while in 28% of the cases the levels were undetectable. From morphological changes of the bioptic sample enhanced atresia of follicules at different developmental stages was frequently observed. It evoked marked reduction of follicular apparatus up to its complete disappearing.

CONCLUSION: The results of our study and mapping of the antiovarian antibodies positivity support our hypothesis that the antiovarian antibodies positivity corresponds with the clinical symptoms. Appropriate treatment with hormonal replacement therapy minimizes ovarian destruction, preserves ovarian hormonal functions and saves healthy ovarian tissue necessary for future fertility....

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Comparative Study 2005; 26(2): 125-130 PubMed PMID: 15855883 Citation  Keywords:  Action Potentials:physiology, Animals, DNA-Binding Proteins:metabolism, Electrophysiology, Hypothalamus:cytology, In Vitro Techniques, Male, Milk Proteins:metabolism, Neurons:metabolism, Prolactin:physiology, Rats, Rats, Wistar, Receptors, Prolactin:metab.   

OBJECTIVES: The study investigated the role of prolactin (PRL) in modulating STAT5 and electrical activity of magnocellular neurones in the supraoptic (SO) nucleus of male rats.

METHODS: Evidence of expression of STAT5 in the SO nucleus was investigated by immunocytochemical methods. Effect of blocking prolactin receptors on STAT 5 expression was investigated by Western blotting following transfection of SO neurones with a dominant negative mutant form of the PRL receptor. Prolactin-induced changes in electrical activity were investigated by extracellular recording in hypothalamic slices.

RESULTS: A high proportion of SO neurones in male rats expressed immunoreactive STAT5. Levels of activated STAT5 within the SO nucleus of PRL-treated rats was reduced following transfection with a dominant negative mutant form of the PRL receptor, as compared to rats transfected with wild type PRL receptor. Electrophysiological recordings from the SO nucleus in horizontal brain slices showed that approximately 25% of neurones were responsive to PRL, with both inhibitory and excitatory effects being observed. Cells displaying PRL responses included pharmacologically-identified oxytocinergic neurones.

CONCLUSIONS: Collectively, the results suggest that central PRL targets neurones of the SO nucleus, influencing both activation of the JAK-STAT signalling pathway and neuronal excitability. Whilst the functional significance of this interaction remains to be established, it might be important in co-ordinating oxytocin secretion with physiological events associated with changes in plasma PRL, or in mediating a feedback loop in the oxytocinergic regulation of lactotrophs....

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Comparative Study 2005; 26(2): 121-124 PubMed PMID: 15855882 Citation  Keywords:  Animals, Exploratory Behavior:drug effects, Female, Habituation, Psychophysiologic:drug effects, Male, Motor Activity:drug effects, Pregnancy, Prenatal Exposure Delayed Effects, Rats, Sex Factors, Testosterone:pharmacology, Vocalization, Animal:drug effec.   

OBJECTIVES: The purpose of the present study was to characterize the influence of testosterone administered to pregnant females on offsprings postnatal behavioral strategies in the open field.

METHODS: The influence of maternal testosterone on behaviour of 23 day old male and female offsprings was studied in a 20-minute open field test. A total of 9 behavioural events were compared between a control (male n=12, female n=8) and a testosterone group (male n=9, female n=9). Dynamics and patterns of association of these behavioural events were analyzed. The testosterone group was prenatally exposed to testosterone (a single intramuscular injection of 2.5 mg testosteroni isobutyras on gestation day 14).

RESULTS: Male offsprings exposed prenatally to testosterone displayed significantly high levels of ambulation (P<0.05), sniffing (P<0.01), sniffing the air (P<0.05), urination (P<0.05) and significantly lower level of vocalization (P<0.05) than control. Female offsprings exposed prenatally to testosterone displayed significantly higher level of sniffing the air (P<0.05) than control. Significant differences in the dynamics of habituation process were registered only in the group of male. They were from 5 to 10 min in ambulation (P<0.05), from 10 to 15 min in sniffing (P<0.05) and vocalization (P<0.05), from 10 to 15 min and from 15 to 20 min in sniffing the air (P<0.05) and from 0 to 5 min in defecation (P<0.05) and urination (P<0.01).

CONCLUSION: Our results suggest that maternal testosterone may influence especially male postnatal open field strategies....

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Comparative Study 2005; 26(2): 113-120 PubMed PMID: 15855881 Citation  Keywords:  Adrenal Medulla:physiology, Adrenalectomy, Animals, Epinephrine:physiology, Fibrosarcoma:chemically induced, Hormones:physiology, Male, Methylcholanthrene, Rats, Rats, Wistar, Transplantation, Autologous, Tumor Burden:physiology,.   

OBJECTIVE: Effects of adrenomedullary hormone(s) on the induction and growth of fibrosarcoma by methylcholanthrene (MC) were examined.

METHODS: At 28 days of age, male Wistar rats were divided into four groups: 1) control, 2) bilateral adrenomedullectomy (Bil. AMX), 3) right AMX + left adrenomedullary autotransplantation (AMX + AMT), 4) Bil. AMX + epinephrine injection (Bil. AMX + E) groups. 14 days after surgery, MC crystals were inserted underneath the dorsal skin, and in the Bil. AMX + E group, epinephrine was injected subcutaneously, twice every week.

RESULTS: The incidence of tumor at 90 days after the MC injection was 8 per 35 cases (22.9%) in the control group, 12 per 36 cases (33.3%) in the AMX + AMT group, 8 per 28 cases (28.6%) in the Bil. AMX + E group, and each value was lower compared with that of the Bil. AMX group, 24 per 34 cases (70.6 %), (P<0.001, P<0.002, P<0.005). Such differences among groups were not seen at 165 days after the injection of MC.

DISCUSSION: The mechanisms of effects of AMX, AMT and/or epinephrine on the tumor incidence have been discussed with reference to tumor promotion, vascular neoplasia, etc. Since norepinephrine remaining in the blood of AMX rats was ineffective, at least it is likely that this inhibitory effect of epinephrine is mediated via the beta2-receptor.

CONCLUSION: The results suggest that adrenomedullary hormone, probably epinephrine, has inhibitory effects on the induction and growth of fibrosarcoma by MC, particularly in the early stage....

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