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Season's appreciations 2002 and 2003. Imaging in time: the transyear (longer-than-the-calendar year) and the half-year.

Halberg F, Cornélissen G, Stoynev A, Ikonomov O, Katinas G, Sampson M, Wang Z, Wan C, Singh R, Otsuka K, Sothern R, Sothern S, Sothern M, Syutkina E, Masalov A, Perfetto F, Tarquini R, Maggioni C, Kumagai Y, Siegelova J, Fiser B, Homolka P, Dusek J, Uezono K, Watanabe Y, Wu J, Prikryl P, Blank M, Blank O, Sonkowsky R, Schwartzkopff O, Hellbrügge T, Spector N, Baciu I, Hriscu M, Bakken E.
Journal Article 2003; 24(6): 479-498 PubMed PMID: 15073580 Citation  Keywords:  Humans, Hypertension:diagnosis, Neuroendocrinology:trends, Periodicity,.   

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Effects of melatonin and oxytetracycline in autologous intraperitoneal ovary transplantation in rats.

Sapmaz E, Ayar A, Celik H, Sapmaz T, Kilic N, Yasar M.
Journal Article 2003; 24(5): 350-354 PubMed PMID: 14647012 Citation  Keywords:  Animals, Anti-Bacterial Agents:pharmacology, Antioxidants:pharmacology, Female, Graft Survival, Malondialdehyde:blood, Melatonin:pharmacology, Necrosis, Ovary:metabolism, Oxytetracycline:pharmacology, Peritoneal Cavity, Rats, Rats, Wistar,.   

OBJECTIVES: To comparatively investigate the effects melatonin and oxytetracycline as antioxidants on autologous intraperitoneal ovary transplantation in rats.

SETTING AND DESIGN: 28 adult female Wistar rats with regular estrous cycles were randomly divided into four groups. Group 1 (n=7) was the control group; Group 2 (n=7) bilateral oophorectomy and intraperitoneal transplantation group; and Groups 3 (n=7) and 4 (n=7) firstly received 20 mg/kg/IP melatonin and 10 mg/kg/IP oxytetracycline., respectively and fifteen minutes after that, they had bilateral oophorectomy and intraperitoneal transplantation. Ovarian tissue and blood malondialdehyde (MDA) levels, superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) levels were determined. Vaginal cytology and ovarian necrosis were histopathologically investigated. Kruskall Wallis analysis of variance was used in the statistical analysis of data.

RESULTS: Ovarian necrosis, tissue MDA and plasma MDA levels were significantly higher in Group 2 compared to the Groups 1, 3 and 4 (p<0.03). SOD and GSHPx levels were significantly lower in group 2 compared to the groups 1, 3 and 4 (p<0.03). Melatonin was found to be more effective on ovarian necrosis and tissue MDA level than the use of oxytetracycline following autologous intraperitoneal ovary transplantation (p<0.03). There was a significant positive correlation between tissue MDA level and ovarian necrosis and a very strong negative correlation between tissue MDA and SOD level (rs = +/-0.9, n=28, p=0.000).

CONCLUSION: Although both melatonin and oxytetracycline were found to be effective in autologous intraperitoneal pelvic ovary transplantation, melatonin is more effective against both the ovarian necrosis and tissue MDA level in rats....

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The effect of intraperitoneal melatonin supplementation on the release of thyroid hormones and testosterone in rats with hyperthyroid.

Mogulkoc R, Baltaci A.
Journal Article 2003; 24(5): 345-347 PubMed PMID: 14647010 Citation  Keywords:  Animals, Antioxidants:pharmacology, Hyperthyroidism:drug therapy, Injections, Intraperitoneal, Male, Melatonin:pharmacology, Rats, Rats, Sprague-Dawley, Testis:drug effects, Testosterone:metabolism, Thyroid Gland:drug effects, Thyroid Hormones:metabolism,.   

OBJECTIVE: Melatonin has a general inhibitory effect on the reproductive system and thyroid functions. Testosterone secretion increases in parallel to thyroid hormones in hyperthyroidism. The aim of this study was to investigate the effects of melatonin application on total T3, T4 and testosterone in hyperthyroid rats.

METHODS: This study was performed on 4 groups each consisted of 6 male Spraque Dawley rats. Control group (G1); sham group (G2); applied 0.5 ml/day of serum physiologic intraperitoneally for 2 weeks, hyperthyroid group (G3); applied 0.3 mg/kg/day thyroxine intraperitoneally for 2 weeks, and hyperthyroid and melatonin supplemented group (G4); applied 0.3 mg/kg/day thyroxine and 3 mg/kg/day melatonin. Blood samples taken by way of decapitation were analysed for total T3, T4 and testosterone by RIA.

RESULTS: Serum total T3 and total testosterone levels were the highest in hyperthyroid group (G3), whereas in hyperthyroid and melatonin supplemented group (G4) were the lowest (P<0.001). Total T4 levels were higher in group 3 than group 1, 2 and 4 (P<0.001).

CONCLUSION: Results revealed that melatonin supplementation in hyperthyroidism suppress secretion of thyroid hormones and testosterone secretion....

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Effect of unilateral superior cervical ganglionectomy on mandibular bone in rats.

Ladizesky M, Lama M, Roldán E, Cutrera R, Boggio V, Giglio M, Cardinali D.
Journal Article 2003; 24(5): 314-320 PubMed PMID: 14647003 Citation  Keywords:  Animals, Bone Density, Female, Mandible:diagnostic imaging, Rats, Rats, Wistar, Superior Cervical Ganglion:surgery, Sympathectomy, Tomography, X-Ray Computed, Tooth Eruption:physiology,.   

OBJECTIVE: To assess the effect of local sympathectomy on mandibular bone during tooth eruption in rats.

METHODS: The effect of a unilateral superior cervical ganglionectomy (Gx) on morphometry of ipsi- and contralateral mandible and volumetric bone density (as assessed by peripheral computed tomography) was examined 30 days after surgery.

RESULTS: Only a few mandibular morphometric parameters decreased significantly after denervation in rats subjected to a unilateral Gx and a contralateral sham-operation. Mandibular volumetric bone density decreased significantly after sympathetic denervation. In a second experiment, carried out under conditions of unilateral unimpeded eruption of incisors performed ipsilaterally or contralaterally to a unilateral Gx, a significant interaction "denervation x type of eruption" was found for most morphometric parameters. Further analysis indicated higher morphometric indexes in denervated mandibles than in the innervated ones under impeded incisor eruption conditions, and lower morphometric indexes in denervated mandibles than in the innervated ones under unimpeded incisor eruption conditions. Unimpeded eruption augmented total volumetric bone density providing the innervation was intact and caused opposite effects on cortical volumetric bone density in the presence of innervation (increase) or absence of innervation (decrease). Trabecular volumetric bone density decreased significantly after sympathetic denervation.

CONCLUSION: The results support a role of the sympathetic nervous system in the regulation of bone remodeling....

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The effects of photoperiod on testes in rat: a morphometric and immunohistochemical study.

Kus I, Akpolat N, Oner H, Ayar A, Pekmez H, Ozen O, Sarsilmaz M.
Journal Article 2003; 24(3-4): 209-214 PubMed PMID: 14523359 Citation  Keywords:  Animals, Immunohistochemistry, Leydig Cells:physiology, Luminescent Measurements, Male, Organ Size:physiology, Photoperiod, Rats, Rats, Wistar, Seminiferous Tubules:anatomy & histology, Testis:anatomy & histology, Testosterone:blood,.   

OBJECTIVE: The aim of this study was to examine the effects of photoperiod on testes in rat.

DESIGN: For this purpose 21 male Wistar rats were used. Animals were divided into three groups. Control rats in group I were kept under 12 hrs light: 12 hrs dark conditions (12L: 12D) for 10 weeks. Animals in group II were exposed to long photoperiods (18L: 6D), while rats in group III were exposed to short photoperiods (6L: 18D) for 10 weeks. At the end of the experiment, all animals were killed by decapitation and blood samples were obtained. Serum testosterone levels were determined with the use of a chemiluminescent enzyme immunoassay. The testes of all rats were removed and weighed. Testicular tissue was processed semiquantitative evaluation of immunohistochemical testosterone staining. Intensity of immunostaining was determined on a scale between 0 (no staining) and 5 (heavy staining). For morphometric comparison, diameters of seminiferous tubules in each group were measured.

RESULTS: In rats exposed to long photoperiods, testicular weights, diameters of seminiferous tubules and serum testosterone levels were significantly increased as compared to those in control rats. Whereas, exposure of rats to short photoperiods resulted in significantly decrease of testicular weights, diameters of seminiferous tubules and serum testosterone levels as compared to those in control rats and rats maintained in long photoperiods. Immunostaining of testosterone was moderate (3+) in control rats, heavy (5+) in rats exposed to long photoperiods and minimal (1+) in rats exposed to short photoperiods.

CONCLUSIONS: The results of our study indicate that testicular functions increase after exposure to long photoperiods and decrease after exposure to short photoperiods....

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Effects of central and peripheral administration of leptin on pain threshold in rats and mice.

Kutlu S, Canpolat S, Sandal S, Ozcan M, Sarsilmaz M, Kelestimur H.
Comparative Study 2003; 24(3-4): 193-196 PubMed PMID: 14523356 Citation  Keywords:  Animals, Hot Temperature, Injections, Intraperitoneal, Injections, Intraventricular, Leptin:administration & dosage, Male, Mice, Pain Measurement:drug effects, Pain Threshold:drug effects, Rats, Rats, Wistar, Reaction Time:drug effects,.   

OBJECTIVE: This study was planned to investigate the effects of exogenous leptin on the pain threshold.

METHODS: Adult male Wistar rats weighing 250-300 g and mice weighing 25-30 g were used in this study. Leptin was intracerebroventricularly (i. c. v.) injected in a dose of 3.5 micro g/rat. Mice were intraperitoneally (i. p.) injected with leptin in a dose of 25 micro g/mouse. Control animals were injected with the respective vehicle. The pain threshold test was performed using hot plate analgesia meter. The experiments were performed during the day and at night. The data were statistically analysed by Mann-Whitney U test. Level of significance was set at p<0.05.

RESULTS: During the day, there were no significant changes in hot plate latencies half an hour after i.c.v. injection of vehicle or leptin in the control and leptin-treated rats, respectively. At night, like during the day, i.c.v. injection of neither vehicle nor leptin caused any significant change in pain sensitivity. In mice, i.p. injection of leptin decreased latencies significantly (p<0.05) during the day and at night. Thus, leptin caused an increase in pain sensitivity during the day and at night.

CONCLUSION: These results clearly demonstrated that leptin has a decreasing-effect on pain threshold if it is peripherally administered in mice....

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