14 research outputs found

    Characteristics of the pituitary immunopositive ACTH cells in rat females after chronic exposure to constant light

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    The effects of chronic exposure to light of adult female Wistar rats on growth and function of pituitary adrenocorticotropes (ACTH cells) were examined. The animals were exposed to continuous light of 600 lux for 95 days, starting on day 30 of age. Control rats were kept under a 12:12 h light-dark cycle, at ambient temperature. ACTH-producing cells were studied using the peroxidase-antiperoxidase immunohistochemical procedure and blood samples were collected for hormone analyses. In animals exposed to a chronic light-treatment all morphometric parameters measured throughout the present study i.e.: ACTH cell volume, nuclear volume and relative volume density were increased by 22% and the differences between this group and the controls were statistically significant (p<0.05). The concentration of plasma ACTH was elevated by 13% in light-exposed group in comparison with the control and this difference was statistically significant (p<0.05), as well. These findings suggest that continuous exposure to light is specifically involved in growth and secretory activity of ACTH cells of adenohypophysis of rat females.Ispitivani su efekti dugotrajnog izlaganja ženki Wistar pacova stalnom svetlu, na adrenokortikotropne (ACTH) ćelije. Eksperimentalne životinje stare 30 dana izlagane su konstantnom svetlu (600 luksa) tokom 95 dana. Kontrolne životinje odgovarajuće starosti su držane na normalnom, 12:12 h dnevno-noćnom režimu i sobnoj temperaturi. ACTH ćelije su imunohistohemijski bojene metodom peroksidaza-antiperoksidaza (PAP), a istovremeno je sakupljana krv za određivanje koncentracije ACTH u plazmi. Životinje izložene stalnom svetlu imale su za 22% povećane sve morfometrijske parametre ACTH ćelija merene tokom ovog rada (zapremina ćelija, njihovih jedara i volumenska gustina) u odnosu na kontrole i uočene razlike su bile statistički značajne (p < 0.05). Koncentracija ACTH u plazmi je takođe bila veća za 13% (p < 0.05) u odnosu na kontrolne vrednosti. Ovi rezultati ukazuju da dugotrajno izlaganje stalnom svetlu na specifičan način stimuliÅ”e rast i sekretornu aktivnost ne samo ACTH ćelija adenohipofize već i ćelija pars intermedia ženki pacova

    The effect of ovariectomy on thyroid c cells of adult rats

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    The structure and function of C cells of adult female rats after ovariectomy (Ovx) were investigated. Intact control and Ovx rats were i.p. treated with sterile olive oil for 4 weeks. Peroxidase-antiperoxidase (PAP) immunohistochemical procedure was applied to localize calcitonin (CT) in thyroid C cells while its serum content was determined by RIA method. Morphometric analyses of the C cells volume, that of their nuclei and relative volume density included stereological method with the multipurpose test system M42. Also, the average number of C cells number per mm2 was calculated. Ovx led to a significant increase in body weight (21%; p<0.005). At the same time the C cells of Ovx rats had a significantly decreased cell volume (13%; p<0.005) and their number per mm2 was increased by 59% (p<0.001) in comparison with the controls. Ovx resulted in reduction of serum CT level by 45% comparing to the corresponding controls. Based on these data it can be concluded that Ovx inhibits both the structure and function of the C cells.U ovom radu ispitivana je struktura i funkcija C ćelija adultnih ženki pacova posle ovarijektomije (Ovx). Intaktne kontrolne i Ovx životinje su tretirane i.p. sterilnim maslinovim uljem u trajanju od četiri nedelje. Za lokalizaciju kalcitonina (CT) u C ćelijama Å”titaste žlezde koriŔćena je imunohistohemijska metoda peroksidaze- antiperoksidaze (PAP). Nivo CT-a u serumu određen je RIA metodom. Morfometrijska ispitivanja volumena C ćelija, njihovih jedara i relativne volumenske gustine ćelija vrÅ”ena su viÅ”enamenskim testnim sistemom M42. Takođe je izračunat broj C ćelija po mm2. Statistička obrada podataka vrÅ”ena je Studentovim t-testom. Posle Ovx-a telesna masa životinja značajno je povećana za 21% (p<0.005). Volumen C ćelija Ovx pacova značajno je smanjen za 13% (p<0.005), njihov broj po mm2 povećan za 59% (p<0.001), a nivo CT-a u serumu smanjen za 45% u poređenju sa intaktnom kontrolom. Na osnovu dobijenih rezultata možemo zaključiti da Ovx deluje inhibitorno na strukturu i funkciju C ćelija Å”titaste žlezde kod pacova

    Vitex agnus-castus L.: Essential oil increases human erythrocyte membrane fluidity

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    Fluidnost membrane eritrocita uslovljava njihove reoloÅ”ke karakteristike, svojevrsne dinamičke kvalitete, izmenjene u hipertenziji i aterosklerozi. Rizik od navedenih i drugih kardiovaskularnih oboljenja se kod žena povećava sa starenjem. Tegobe koje prate menopauzu se obično ublažavaju supstitucionom hormonskom terapijom, koja može povećati rizik od pojave malignih oboljenja. Esencijalno ulje biljke Vitex agnus-castus L. sadrži različita organska jedinjenja (monoterpene, seskviterpene i terpenoide) i sve čeŔće se koristi kao alternativno terapijsko sredstvo za simptome menopauze. Navedene komponente esencijalnog ulja mogu se ugraditi u ćelijske membrane i menjati njihovu fluidnost. Cilj studije bio je da se utvrde efekti esencijalnog ulja biljke Vitex agnus-castus na fluidnost membrane eritrocita po njenoj du bini. KoriŔćena je spektroskopija elektronske paramagnetne rezonance i masnokiselinske spinske probe (5-doksil stearinska i 12-doksil stearinska kiselina), čiji spektri za vise od fluidnosti membrane. Nakon tretmana eritrocita esencijalnim uljem biljke Vitex agnus-castus utvrđeno je značajno (p=0,029) i reverzibilno povećanje fluidnosti njihove membrane u dubljim, hidrofobnim regionima, dok u povrÅ”inskim, hidrofilnim regionima eritrocitne membrane nisu utvrđene značajne promene (p>0,05). Ovi rezultati ukazuju na povećanje fluidnosti eritrocitne membrane nakon tretmana esencijalnim uljem biljke Vitex agnus-castus, Å”to može biti koristan efekat pri tretmanu pacijentkinja sa hipertenzijom i drugim kardiovaskularnim oboljenjima u menopauzi.Erythrocyte membrane fluidity is related to their rheologic behavior, the dynamic quality of erythrocytes, which is tempted in hypertension and atherosclerosis. An increased risk of these and other cardiovascular diseases occurs in ageing women. Menopause-related conditions are often treated with hormone replacement therapy that may increase the risk of malignancies. Vitex agnus-castus L. essential oil contains various organic compounds (monoterpenes, sesquiterpenes and terpenoids), and is increasingly used as an alternative therapy for menopausal symptoms. These components of the oil may be incorporated into cell membranes, thereby changing the membrane fluidity. The aim of this study was to determine the effects of Vitex agnuscastus essential oil on human erythrocyte membrane fluidity at graded depths. We used Electron Paramagnetic Resonance spectroscopy and fatty acid spin probes (5-doxyl stearic acid and 12-doxyl stearic acid), whose spectra depend on membrane fluidity. After treatment with Vitex agnus-castus essential oil the erythrocytes had a significant (p=0.029) and reversible increase in membrane fluidity in the deeper hydrophobic membrane regions, with no change (p>0.05) in fluidity near the membrane's hydrophilic surface. These results document increased fluidity of the human erythrocyte membrane by Vitex agnus-castus essential oil, and this action may be useful in patients with menopause-related hypertension and other cardiovascular conditions

    Effects of intracerebroventricularly administered octreotide on gonadotrophic cells in female rats

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    Effects of intracerbroventricularly (ICV) administered octreotide on gonadotrophic cells (FSH and LH) of adult Wistar female rats were examined by immunocytochemical and morphometric methods. The animals received ICV three 1.0 mg doses of octreotide dissolved in 10 mL saline every second day. The controls were treated with equivalent volume of physiological saline by the same schedule. FSH- and LH-producing cells were examined using peroxidase-antiperoxidase immunocytochemical procedure. Morphometric and stereologic examinations were performed to evaluate changes in the number, volume and volume densities of gonadotrophic cells. In females treated with octreotide, the gonadotrophic cells were smaller and often pycnotic, while the number of FSH- and LH-immunopositive cells per unit area (mm2) was significantly reduced. Octreotide also induced a significant reduction of the FSH- and LH-immunoreactive cells volume, as well as of their volume densities. On the basis of these results it can be concluded that octeotride, centrally administered to adult female rats provokes changes in immunocytochemical and morphometric features of both types of gonadotrophic cells.Ispitivani su efekti oktreotida davanog intracerebroventrikularno (ICV) odraslim ženkama pacova na gonadotropne ćelije (FSH i LH). Životinje su tretirane sa ukupno tri doze od 1 mg oktreotida rastvorenog u 10 mL fizioloÅ”kog rastvora svakog drugog dana. Kontrole su na isti način primile odgovarajuću zapreminu fizioloÅ” kog rastvora. FSH i LH ćelije su ispitivane imunocitohemijskim postupkom peroksidaza-antiperoksidaza. Da bi se ustanovile promene u broju, zapremini i zapreminskoj gustini gonadotropnih ćelija primenjen je morfometrijski kao i stereoloÅ”ki pristup. Kod ženki tretiranih oktreotidom, gonadotropne ćelije su bile manje i često piknotič ne. Broj imunopozitivnih FSH i LH ćelija po jedinici povrÅ”ine (mm2) je bio statistički značajno smanjen. Oktreotid je, takodje, izazvao značajno smanjenje zapremine FSH i LH imunoreaktivnih ćelija, kao i njihove zapreminske gustine. Na osnovu ovih rezultata, može se zaključiti da je oktreotid, dat ICV odraslim ženkama pacova doveo do promena imunocitohemijskih i morfometrijskih osobina oba ispitivana tipa gonadotropnih ćelija

    Characteristics of the pituitary immunopositive ACTH cells in rat females after chronic exposure to constant light

    Get PDF
    The effects of chronic exposure to light of adult female Wistar rats on growth and function of pituitary adrenocorticotropes (ACTH cells) were examined. The animals were exposed to continuous light of 600 lux for 95 days, starting on day 30 of age. Control rats were kept under a 12:12 h light-dark cycle, at ambient temperature. ACTH-producing cells were studied using the peroxidase-antiperoxidase immunohistochemical procedure and blood samples were collected for hormone analyses. In animals exposed to a chronic light-treatment all morphometric parameters measured throughout the present study i.e.: ACTH cell volume, nuclear volume and relative volume density were increased by 22% and the differences between this group and the controls were statistically significant (p<0.05). The concentration of plasma ACTH was elevated by 13% in light-exposed group in comparison with the control and this difference was statistically significant (p<0.05), as well. These findings suggest that continuous exposure to light is specifically involved in growth and secretory activity of ACTH cells of adenohypophysis of rat females.Ispitivani su efekti dugotrajnog izlaganja ženki Wistar pacova stalnom svetlu, na adrenokortikotropne (ACTH) ćelije. Eksperimentalne životinje stare 30 dana izlagane su konstantnom svetlu (600 luksa) tokom 95 dana. Kontrolne životinje odgovarajuće starosti su držane na normalnom, 12:12 h dnevno-noćnom režimu i sobnoj temperaturi. ACTH ćelije su imunohistohemijski bojene metodom peroksidaza-antiperoksidaza (PAP), a istovremeno je sakupljana krv za određivanje koncentracije ACTH u plazmi. Životinje izložene stalnom svetlu imale su za 22% povećane sve morfometrijske parametre ACTH ćelija merene tokom ovog rada (zapremina ćelija, njihovih jedara i volumenska gustina) u odnosu na kontrole i uočene razlike su bile statistički značajne (p < 0.05). Koncentracija ACTH u plazmi je takođe bila veća za 13% (p < 0.05) u odnosu na kontrolne vrednosti. Ovi rezultati ukazuju da dugotrajno izlaganje stalnom svetlu na specifičan način stimuliÅ”e rast i sekretornu aktivnost ne samo ACTH ćelija adenohipofize već i ćelija pars intermedia ženki pacova

    The effect of ovariectomy on thyroid c cells of adult rats

    Get PDF
    The structure and function of C cells of adult female rats after ovariectomy (Ovx) were investigated. Intact control and Ovx rats were i.p. treated with sterile olive oil for 4 weeks. Peroxidase-antiperoxidase (PAP) immunohistochemical procedure was applied to localize calcitonin (CT) in thyroid C cells while its serum content was determined by RIA method. Morphometric analyses of the C cells volume, that of their nuclei and relative volume density included stereological method with the multipurpose test system M42. Also, the average number of C cells number per mm2 was calculated. Ovx led to a significant increase in body weight (21%; p<0.005). At the same time the C cells of Ovx rats had a significantly decreased cell volume (13%; p<0.005) and their number per mm2 was increased by 59% (p<0.001) in comparison with the controls. Ovx resulted in reduction of serum CT level by 45% comparing to the corresponding controls. Based on these data it can be concluded that Ovx inhibits both the structure and function of the C cells.U ovom radu ispitivana je struktura i funkcija C ćelija adultnih ženki pacova posle ovarijektomije (Ovx). Intaktne kontrolne i Ovx životinje su tretirane i.p. sterilnim maslinovim uljem u trajanju od četiri nedelje. Za lokalizaciju kalcitonina (CT) u C ćelijama Å”titaste žlezde koriŔćena je imunohistohemijska metoda peroksidaze- antiperoksidaze (PAP). Nivo CT-a u serumu određen je RIA metodom. Morfometrijska ispitivanja volumena C ćelija, njihovih jedara i relativne volumenske gustine ćelija vrÅ”ena su viÅ”enamenskim testnim sistemom M42. Takođe je izračunat broj C ćelija po mm2. Statistička obrada podataka vrÅ”ena je Studentovim t-testom. Posle Ovx-a telesna masa životinja značajno je povećana za 21% (p<0.005). Volumen C ćelija Ovx pacova značajno je smanjen za 13% (p<0.005), njihov broj po mm2 povećan za 59% (p<0.001), a nivo CT-a u serumu smanjen za 45% u poređenju sa intaktnom kontrolom. Na osnovu dobijenih rezultata možemo zaključiti da Ovx deluje inhibitorno na strukturu i funkciju C ćelija Å”titaste žlezde kod pacova

    Effects of intracerebroventricularly administered octreotide on gonadotrophic cells in female rats

    Get PDF
    Effects of intracerbroventricularly (ICV) administered octreotide on gonadotrophic cells (FSH and LH) of adult Wistar female rats were examined by immunocytochemical and morphometric methods. The animals received ICV three 1.0 mg doses of octreotide dissolved in 10 mL saline every second day. The controls were treated with equivalent volume of physiological saline by the same schedule. FSH- and LH-producing cells were examined using peroxidase-antiperoxidase immunocytochemical procedure. Morphometric and stereologic examinations were performed to evaluate changes in the number, volume and volume densities of gonadotrophic cells. In females treated with octreotide, the gonadotrophic cells were smaller and often pycnotic, while the number of FSH- and LH-immunopositive cells per unit area (mm2) was significantly reduced. Octreotide also induced a significant reduction of the FSH- and LH-immunoreactive cells volume, as well as of their volume densities. On the basis of these results it can be concluded that octeotride, centrally administered to adult female rats provokes changes in immunocytochemical and morphometric features of both types of gonadotrophic cells.Ispitivani su efekti oktreotida davanog intracerebroventrikularno (ICV) odraslim ženkama pacova na gonadotropne ćelije (FSH i LH). Životinje su tretirane sa ukupno tri doze od 1 mg oktreotida rastvorenog u 10 mL fizioloÅ”kog rastvora svakog drugog dana. Kontrole su na isti način primile odgovarajuću zapreminu fizioloÅ” kog rastvora. FSH i LH ćelije su ispitivane imunocitohemijskim postupkom peroksidaza-antiperoksidaza. Da bi se ustanovile promene u broju, zapremini i zapreminskoj gustini gonadotropnih ćelija primenjen je morfometrijski kao i stereoloÅ”ki pristup. Kod ženki tretiranih oktreotidom, gonadotropne ćelije su bile manje i često piknotič ne. Broj imunopozitivnih FSH i LH ćelija po jedinici povrÅ”ine (mm2) je bio statistički značajno smanjen. Oktreotid je, takodje, izazvao značajno smanjenje zapremine FSH i LH imunoreaktivnih ćelija, kao i njihove zapreminske gustine. Na osnovu ovih rezultata, može se zaključiti da je oktreotid, dat ICV odraslim ženkama pacova doveo do promena imunocitohemijskih i morfometrijskih osobina oba ispitivana tipa gonadotropnih ćelija

    Biologia Futura: does the aging process contribute to the relativity of time?

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    In his Theory of relativity, Einstein determined that the time is relative to the reference frame of the observer. Under specific conditions, there is a difference in the elapsed time between two clocks, known as time dilation. A similar relativistic effect could be attributed to the brain operating at different frequencies, e.g., while it is slow and during the thought process. Time flow and the aging process are causally linked. Herein, we introduce physical relativity into the mind/thought context and elaborate changed perception of the time flow (the impression of the time acceleration) with aging. The phenomenology of time is observed in the context of physical and biological clock, as well as by introducing the category of ā€˜mind time.ā€™ Mental processing impairment is crucial for the ā€œaging-caused relativity of time,ā€ while adjusting of itsā€™ perception seems to be a matter of body/mind rest, mental hygiene and physical activity of the aging subject. We also provide a brief overview of the percep- tion of time flow in some disease states that coincide with aging. Our main idea has a perspective for future development in the interdisciplinary synergy of philosophy, physicalā€“mathematical elaboration, experimental biology and clinical investigations

    Daidzein effects on ACTH cells: immunohistomorphometric and hormonal study in an animal model of the andropause

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    Daidzein is a potential natural alternative to estradiol during therapy of some malignancies in men. Besides weak inhibition of tyrosine kinase activity, daidzein has a sizeable inhibitory effect on calcium channels. The aim of this study was to examine the effects of daidzein on the immunohistomorphometric features of pituitary adrenocorticotropes (ACTH cells) and circulating levels of ACTH and corticosterone, in comparison with estradiol, in an animal model of the andropause. Sixteen-month-old Wistar rats were divided into sham operated (SO), orchidectomized (Orx), estradiol treated orchidectomized (Orx+E) and daidzein treated orchidectomized (Orx+D) groups. Estradiol (0.625 mg/kg/day) and daidzein (30 mg/kg/day) were administered subcutaneously for three weeks, while the SO and Orx groups received the vehicle alone. ACTH cells were identified by the peroxidase-antiperoxidase (PAP) immunohistochemical procedure. Peripheral circulating concentrations of ACTH and corticosterone were measured by immunoassay. Orchidectomy reduced (p<0.05) the cell volume and volume density of adrenocorticotropes by 11% and 16%, respectively, in comparison to SO rats. In Orx+E rats, the volume density of ACTH cells decreased (p<0.05) by 25%, but the circulating level of ACTH increased (p<0.05) by 29%, compared to Orx rats. Daidzein treatment significantly decreased (p<0.05): volume density of ACTH cells, circulating ACTH and corticosterone by 24%, 48% and 33%, respectively, compared to the Orx group. In conclusion, this study revealed that daidzein negatively modulated the immunohistomorphometric features of ACTH cells and, unlike estradiol, decreased ACTH and corticosterone secretion, in an animal model of the andropause

    Improving the Throughput of Distributed Hash Tables Using Congestion-Aware Routing

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    Advanced applications for Distributed Hash Tables (DHTs), such as Peer-to-Peer Information Retrieval, require a DHT to quickly and efficiently process a large number (in the order of millions) of requests. In this paper we study mechanisms to optimize the throughput of DHTs. Our goal is to maximize the number of route operations per peer per second a DHT can perform (given certain constraints on the lookup delay). Each peer receives congestion feedback from the DHT, which it uses to adjust its routing decisions. This way, peers can avoid routing through slow parts of the overlay network and hence increase the rate at which they insert new messages into the DHT.We provide a numerical analysis of congestion-aware routing in DHTs and show that considerable improvements in throughput are possible compared to DHTs with proximity neighbor selection and strictly greedy routing
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