Adenine nucleotide translocation in liver mitochondria of hypothyroid rats

Hoch, Frederic L.

doi:10.1016/0003-9861(77)90224-7

Cited by 65 publications

(33 citation statements)

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“…Thyroid hormones, especially T 3 , are known to be thermogenic. They stimulate oxidative phosphorylation and ATP exportation [12,14] and mitochondria biogenesis [9]. Their decreased concentrations at high temperature [21,32] are consistent with the reduction in heat production in observed in such conditions [23,27].…”

Section: Discussionmentioning

confidence: 66%

Effects of high temperature on body temperature and hormonal adjustments in piglets

2002

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-Effects of a high (33°C) or thermoneutral (23 °C) temperature on body temperature and endocrine parameters were studied in weaned piglets. Rectal and skin temperatures were measured in four ad libitum fed animals per temperature during three weeks. After this acclimation period, 11 blood samples were withdrawn on a 24-h period. Over the acclimation period, rectal and skin temperatures were 0.6 and 2.9°C higher, respectively, at 33°C than at 23°C (P < 0.01), this change occurring from the 1st day at 23 or 33°C. A tendency of serum leptin concentrations to be lower after meals at 33°C than at 23°C was also displayed (P = 0.09). Plasmatic concentrations in Insulin-like growth factor I and thyroxine were decreased at 33°C relative to 23°C (P < 0.01 and P < 0.06, respectively), and triiodothyronine concentrations tended to be lower at 33°C than at 23°C (P = 0.1), which could account for the lower heat production and growth observed in pigs exposed to high temperatures.piglet / heat exposure / body temperature / thyroid hormones / IGF-I Résumé -Effets d'une température ambiante élevée sur la température corporelle et les ajustements hormonaux chez le porcelet sevré. Les effets d'une température ambiante élevée (33°C) ou thermoneutre (23°C) sur la température corporelle et le statut hormonal sont étudiés chez le porcelet sevré. Les températures rectale et cutanée sont mesurées sur 4 animaux par tempé-rature, nourris à volonté et acclimatés à la température expérimentale pendant trois semaines. Après cette période, les paramètres sanguins sont mesurés sur 11 échantillons prélevés sur un nycthémère. Au cours de la période d'acclimatation, les températures rectale et cutanée sont rapidement supérieures à 33°C qu'à 23°C, respectivement de 0,6 et 2,9°C (P < 0,01). Les concentrations sériques en leptine tendent à être inférieures à 33°C à l'état nourri (P = 0,09). Les taux d'Insulin-like growth factor I et thyroxine plasmatiques sont plus faibles à 33 qu'à 23°C (respectivement P < 0,01 et P < 0,06), et les concentrations en triiodothyronine tendent à être inférieures à 33°C (P = 0,1), en accord avec la production de chaleur et la croissance plus faible de ces animaux au chaud.porcelet / chaleur / température corporelle / hormones thyroïdiennes / IGF-I Reprod. Nutr. Dev. 42 (2002) 45-53 45

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Section: Discussionmentioning

confidence: 66%

Effects of high temperature on body temperature and hormonal adjustments in piglets

2002

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“…Fig. 1 presents data from one such experiment plotted according t o Eqn (9) and demonstrates that, a t least for the initial rapid exchange, the suposition is valid. This was found t o be the case with both euthyroid and hypothyroid preparations.…”

Section: The Effect Of' Inhihitars Of Phohphorylutianmentioning

confidence: 99%

“…One potential component in this lowered phosphorylating ability may be the reduced rate of adenine nucleotide translocation found in hypothyroid mitochondria [8,9], since the recent elegant experiments of Tager and his co-workers [lo, 1 I] have shown that a significant measure of control of oxidative phosphorylation is exerted by the transfer. Portnay et al [8] found that the lowered translocation rate was increased after 6 days of thyroxine replacement therapy to hypothyroid ani- mals: in experiments with normal animals, the same group [12] had shown that a single large dose of triiodothyronine increased translocator activity after 3 days but not significantly after 20 h. If lowered adenine nucleotide translocation can contribute, at least in some measure, to the reduced ADPjO ratio then the translocator rate ought to respond within 15 min of hormone administration just as the ratio does.…”

Section: The Mitochondrion Has Long Been Considered a Likely Subcellumentioning

confidence: 99%

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“…We have established conditions under which liver mitochondria from thyroidectomised rats show ADPjO ratios with both NAD' and FAD-linked substrates of 50-70% of those obtained using preparations from euthyroid animals with no loss of respiratory control [3,6]. Mitochondria from thyroidectomised rats isolated 15 min after intravenous injection of a physiological dose of hormone or isolated after incubation with hormone and other cell fractions showed ADPjO ratios and respiratory control ratios indistinguishable from those obtained with euthyroid preparations although the low rates of respiration per mass of protein were unchanged [3, 6, 71.One potential component in this lowered phosphorylating ability may be the reduced rate of adenine nucleotide translocation found in hypothyroid mitochondria [8,9], since the recent elegant experiments of Tager and his co-workers [lo, 1 I] have shown that a significant measure of control of oxidative phosphorylation is exerted by the transfer. Portnay et al [8] found that the lowered translocation rate was increased after 6 days of thyroxine replacement therapy to hypothyroid aniEnzymes.…”

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Short‐term control of mitochondrial adenine nucleotide translocator by thyroid hormone

Mowbray¹,

Corrigall²

1984

European Journal of Biochemistry

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1. An improved simple technique for measuring adenine nucleotide translocator activity at low medium substrate concentrations is described.2. Confirming previous reports, thyroidectomy was shown to lead to lowered translocator activity in rat liver mitochondria. The rapidly exchangeable portion of the matrix nucleotide also decreased in hypothyroid preparations even though the total nucleotides increased substantially.3. The apparent K,,, of translocator for ADP increased from 2.8 to 6.2pM in hypothyroid preparations: Mg2+ ions raised this to about 20 pM.4. All of these changes in adenine nucleotide translocation were entirely reversed by 15min after a single intravenous near-physiological dose of triiodothyronine.The mitochondrion has long been considered a likely subcellular target of thyroid hormone action (review [I]). Mitochondria have been shown to acquire iodine [2] and triiodothyronine [3] at very short times after radiohormone administration to hypothyroid animals and a proteolipid fraction with specific tight binding sites for the hormone has been isolated from rat liver mitochondrial inner membrane [4].Rapid effects of hormone on oxidative phosphorylation have also been observed. Hoch [2] found changes in respiratory control and uncoupler sensitivity 2 min after thyroxine injection to hypothyroid rats; Sterling and his co-workers have reported increased phosphorylation in sub-mitochondrial vesicles both using direct addition of nanomolar hormone concentrations [5] and with vesicles prepared 30 rnin after injection of a near-physiological dose of triiodothyronine [I]. We have established conditions under which liver mitochondria from thyroidectomised rats show ADPjO ratios with both NAD' and FAD-linked substrates of 50-70% of those obtained using preparations from euthyroid animals with no loss of respiratory control [3,6]. Mitochondria from thyroidectomised rats isolated 15 min after intravenous injection of a physiological dose of hormone or isolated after incubation with hormone and other cell fractions showed ADPjO ratios and respiratory control ratios indistinguishable from those obtained with euthyroid preparations although the low rates of respiration per mass of protein were unchanged [3, 6, 71.One potential component in this lowered phosphorylating ability may be the reduced rate of adenine nucleotide translocation found in hypothyroid mitochondria [8,9], since the recent elegant experiments of Tager and his co-workers [lo, 1 I] have shown that a significant measure of control of oxidative phosphorylation is exerted by the transfer. Portnay et al. [8] found that the lowered translocation rate was increased after 6 days of thyroxine replacement therapy to hypothyroid aniEnzymes. Hexokinase (EC 2.7.1.1); pyruvate kinase (EC 2.7.1.40); lactate dehydrogenase (EC 3.1.1.27); adenylate kinase (EC 2.7.4.3); glucose-6-phosphate dehydrogenase (EC 1 .I .1.49). mals: in experiments with normal animals, the same group [12] had shown that a single large dose of triiodothyronine increased translocator activi...

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Thyroid hormones and the creatine kinase system in cardiac cells

Seppet

Saks

1994

Cellular Bioenergetics: Role of Coupled Creatine Kinases

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The paper reviews the current evidence on the role of thyroid hormones in regulating the creatine kinase energy transfer system at multiple structures in cardiac cells. 1) Thyroid hormones modulate the overall synthesis of phosphocreatine (PCr) by increasing the rate of mitochondrial oxidative phosphorylation. 2) Thyroid hormones regulate the total activity of creatine kinase and its isoenzyme distribution. In comparison with normal thyroid state (euthyroidism), hypothyroidism is characterized by decreased total creatine kinase activity owing to diminished fraction of creatine kinase. On the other hand, hyperthyroidism, while causing no change in total creatine kinase activity, leads to increased fractions of neonatal isoforms of creatine kinase, and, in case of prolonged hyperthyroidism, to decreased fraction of mitochondrial creatine kinase. The latter change is associated with partial uncoupling between mitochondrial creatine kinase and adenine nucleotide translocase reflected by decreased PCr/O ratio. 3) Hyperthyroidism leads to increased passive sarcolemmal permeability due to which the leakage of creatine along its concentration gradient occurs. As a result of (i) increased sarcolemmal permeability for creatine, (ii) uncoupling of mitochondrial PCr synthesis, and (iii) increased energy utilization rate the steady state intracellular PCr content decreases under hyperthyroidism which, in turn, increases the myocardial susceptibility to hypoxic damage. Thyroid state also modulates the protective effects of exogenous PCr on energetically depleted myocardium. (Mol Cell Biochem 133/134: 299-309, 1994)

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Adenine nucleotide translocation in liver mitochondria of hypothyroid rats

Cited by 65 publications

References 31 publications

Effects of high temperature on body temperature and hormonal adjustments in piglets

Effects of high temperature on body temperature and hormonal adjustments in piglets

Short‐term control of mitochondrial adenine nucleotide translocator by thyroid hormone

Thyroid hormones and the creatine kinase system in cardiac cells

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