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Acta Veterinaria Hungarica
Authors: Á. Klein, Margit Kulcsár, Virág Krízsik, R. Mátics, P. Rudas, J. Török and Gy. Huszenicza

The basic patterns of thyroid hormones [thyroxine (T4) and 3,3',5-triiodothyronine (T3)] and the T4 and T3 responses induced by thyrotropin releasing hormone (TRH) are reported in captive female barn owls (Tyto alba) during the non-breeding period. The main findings of the study, conducted on a total of 10 owls, are as follow: (1) The thyroid gland of barn owl can be stimulated by the classical TRH stimulation test. (2) T3 response was much more pronounced both under cold (around 10°C) and warm (around 20°C) conditions, whereas T4 response ranged so widely that we could not point out any significant change in it. (3) Basal T3 plasma level was significantly (p = 0.036) higher in birds exposed to cold temperature, and they responded to TRH treatment with a lower plasma T3 elevation than the birds kept in a warm chamber. This pattern, however, cannot be explained by increased food intake, but is in agreement with the fact that enhanced T3 level may account for higher avUCP mRNA expression, which results in higher heat production on the cell level. From the results it is concluded that altering T3 plasma level plays a significant role in cold-induced thermoregulation.

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Pétervári E, Balaskó M, Szelényi Z, Hummel Z, Székely M: Fasting hypometabolism and thermoregulation in cold-adapted rats. J. Thermal Biol. 27, 359-364 (2002) Fasting hypometabolism and thermoregulation in cold-adapted rats

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Abstract  

Thermal investigations were performed on a colony of the Colombian stingless bee Trigona (Frieseomelitta) nigra paupera by means of thermometry and direct calorimetry. A nest with about 2000 individuals was transferred to a twin calorimeter, where the bees continued their normal life and development. Two camping boxes (‘Poor Man’s Calorimeter, PMC’) with Peltier elements as cooling systems were used as a differential system. Each box had a volume of 8 L and a sensitivity of 19.2 mV W−1. The colony was monitored calorimetrically and thermometrically with resistors distributed in the nest. Signals were recorded continuously by a four-channel data logger.

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changes of temperature differences in chosen areas may suggest some influence of hyperbaric oxygenation on the thermoregulation process in tissues. A similar decrease of Δ T was observed for the healthy group; however, the values captured were smaller

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. 2003 ; 189 : 599 – 607 . 10.1007/s00359-003-0436-9 . 12. Schmolz , E , Hoffmeister , D , Lamprecht , I . Calorimetric investigations on metabolic rates and thermoregulation of

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Abstract

Seabirds are considered ecosystem engineers, because they facilitate ecosystem functioning (e.g., nutrient cycling), crucial for other marine and terrestrial species, including reptiles. However, studies of seabird-reptile interactions are limited. Here, we assessed the influence of the ‘Critically Endangered’ Whenua Hou Diving Petrel (Pelecanoides whenuahouensis) on the occurrence of two threatened skinks, Stewart Island green skink (Oligosoma aff. chloronoton) and southern grass skink (O. aff. polychroma). We surveyed skinks for 26 consecutive days at 51 sites with and 48 sites without Diving Petrel burrows in the dunes on Codfish Island (Whenua Hou), New Zealand. We used occupancy modelling to assess the influence of burrows on the occurrence of skinks, while accounting for other factors affecting occupancy (Ψ) and detection probabilities (p). Diving Petrel burrows had a contrasting effect on the occurrence of skinks. On average, Ψ̂ of Stewart Island green skinks was 114% higher at sites with burrows compared to sites without, while Ψ̂ of southern grass skinks was only 2% higher. Occurrence of both skinks was negatively influenced by the presence of the other skink species. On average p̂ were low: 0.013 and 0.038 for Stewart Island green and southern grass skinks, respectively. Stewart Island green skinks appear attracted to burrows, which might facilitate thermoregulation (i.e., shelter from temperature extremes). The larger Stewart Island green skinks may subsequently exclude the smaller southern grass skinks at burrows, causing the contrasting relationships. We suggest that these interspecific interactions should be considered when implementing conservation management, e.g., through the order of species reintroductions.

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A központi idegrendszer és az endokrin rendszer kapcsolata rendkívül összetett. Az autonóm működéseket a hypothalamus neuronális és hormonális úton integrálja, biztosítja a szervezet homeosztázisát, koordinálja növekedési és szaporodási funkcióit, a stresszreakciókat, az élettani folyamatok ritmicitását, periodicitását és időzítését. Az általa termelt hormonok közül az antidiuretikus hormonnak a jól ismert hatásain túl szerepe van a szociális viselkedésben, mivel a vazopresszin-1A receptoron keresztül fokozza az agressziót. Az oxitocin az anyai viselkedés kialakítása mellett más szociális interakciókban, a párkapcsolati kötődésben, valamint az analgesiában és a fájdalom modulálásában játszik szerepet. A corticotrop-releasing hormon neurotranszmitterként is működik, kitüntetett szerepe van a stresszviselkedésben, szorongásban és depresszióban, erősen gátolja a mély alvást. Az evészavarok kialakulásában a hypothalamus neurotranszmitterei és neuropeptidjei közül a szerotoninnak, noradrenalinnak, GABA-nak, kolecisztokininnek, neuropeptid Y-nak, Agouti-related proteinnek, α-melanocyta-stimuláló hormonnak és ghrelinnek van alapvető jelentősége, a leptin- és galaninszintek határozzák meg, hogy anabolikus vagy katabolikus neurotranszmitterek képződjenek. A hőszabályozásban a centrális termoreceptorok játszanak szerepet, a cirkadián ritmusért a nucleus suprachiasmaticus főként „időzítő géneken” keresztül felelős. A hypothalamicus kórképek leggyakrabban bulimiához vagy anorexiához, hypersomniához, impotenciához, szorongásos attakokhoz vezetnek. Leggyakoribb térszűkítő folyamata a craniopharyngeoma. A vazopresszin-elválasztás hiánya vagy csökkenése diabetes insipidust, míg a túlzott mennyiségben képződő vazopresszin Schwartz–Barter-szindrómát okoz. A Fröhlich-, Kleine–Levin- és a Prader–Willi-szindróma jellegzetes neuropszichiátriai eltérésekkel jár. A hypophysis hipofunkció pszichiátriai képét a demencia-delírium kombináció jellemzi, a hypophysis-adenomák legjellegzetesebb neurológiai tünete a látótérkiesés. A somatotrop adenomák okozta tipikus neurológiai eltérések a carpal tunnel-szindróma, az obstruktív alvási apnoe és a fejfájás.

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Orvosi Hetilap
Authors: Júlia Szabó, Dénes Zádori, Edina Tímea Varga and László Vécsei

Pazderska, A., O’Connell, M., Pender, N., et al.: Insights into thermoregulation: A clinico-radiological description of Shapiro syndrome. J. Neurol. Sci., 2013, 329 (1–2), 66–68.

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Viswanathan M, Laitinen JT, Saavedra JM: Expression of melatonin receptors in arteries involved in thermoregulation. Proc. Natl. Acad. Sci. USA. 87, 6200-6203 (1990) Expression of melatonin receptors in arteries involved in

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Controlling, ed. Morrison JL, NOVA Publishers, pp. 83–104 https://www.novapublishers.com/catalog/product_info.php?products_id=19499 Szekely M, Petervari E, Balasko M: Thermoregulation, energy balance, regulatory

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