Search results for "homeostasi"

Magnesium metabolism in hypertension and type 2 diabetes mellitus.

2007

The increasing evidence for the clinical relevance of altered magnesium metabolism to states of altered insulin resistance confirms the role of magnesium deficit as a possible underlying common mechanism of the "insulin resistance" of hypertension and altered glucose tolerance. The pioneer work of Lawrence M. Resnick and his group using the cellular ion-based approach that we are only partially presenting here has consistently contributed to the progress of the field, demonstrating (a) the critical importance of magnesium metabolism in regulating insulin sensitivity as well as vascular tone, and blood-pressure homeostasis; (b) that magnesium deficiency, defined on the basis of intracellular…

Base Excess and Lactate Concentration in Infusion Solutions and Blood Products

2002

PGC-1α: a master gene that is hard to master

2012

Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a transcriptional coactivator that favorably affects mitochondrial function. This concept is supported by an increasing amount of data including studies in PGC-1α gene-deleted mice, suggesting that PGC-1α is a rescue factor capable of boosting cell metabolism and promoting cell survival. However, this view has now been called into question by a recent study showing that adeno-associated virus-mediated PGC-1α overexpression causes overt cell degeneration in dopaminergic neurons. How is this to be understood, and can these seemingly conflicting findings tell us something about the role of PGC-1α in cell stress and in cont…

Glucose homeostasis is impaired in mice deficient for the neuropeptide 26RFa (QRFP)

2019

AbstractIntroduction26RFa (QRFP) is a biologically active peptide that has been found to control feeding behaviour by stimulating food intake, and to regulate glucose homeostasis by acting as an incretin. The aim of the present study was thus to investigate the impact of 26RFa gene knockout on the regulation of energy and glucose metabolism.Research design and methods26RFa mutant mice were generated by homologous recombination, in which the entire coding region of prepro-26RFa was replaced by the iCre sequence. Energy and glucose metabolism was evaluated through measurement of complementary parameters. Morphological and physiological alterations of the pancreatic islets were also investigat…

Possibilities and necessities of parenteral nutrition with amino acid mixtures.

1975

In recent years, there have been conclusive findings in the field of maintaining homeostasis following trauma, bleeding, nutritional and metabolic disturbances and infections. These findings can help save the lives of an increasing number of injured and sick by enlarging the therapeutic possibilities which have previously been unimaginable. This development has been made possible by the good cooperation of both basic research and clinical staff whose common aim was to achieve advances in this field of intensive care. The aim of the present study is to make a relevant theoretical and practical contribution to the widening possibilities and necessities in this field.

Role of the gamma-glutamyl cycle in the regulation of amino acid translocation

1989

Amino acid translocation was studied in the mammary gland of lactating rats and in the placenta of pregnant rats. The uptake of amino acids by the mammary gland is maximal on days 10-14 of lactation and is minimal on days 19-21. However, on day 19 maximal uptake can be restored by injection of 1) small amounts of gamma-glutamyl amino acids, 2) 5-oxoproline, and 3) an inhibitor of 5-oxoprolinase. A severe decrease in uptake of amino acids at the peak of lactation is provoked by anthglutin, an inhibitor of gamma-glutamyltranspeptidase (GGT). Simultaneous injection of 5-oxoproline blocks these effects of anthglutin. In pregnant rats, inhibition (79%) of placental GGT activity by acivicin resul…

Are skeletal muscleFNDC5gene expression and irisin release regulated by exercise and related to health?

2013

Recently, contradictory findings have been reported concerning the function of irisin and its precursor gene, skeletal muscle FNDC5, in energy homeostasis, and the associated regulatory role of exercise and PGC-1α. We therefore evaluated whether muscle FNDC5 mRNA and serum irisin are exercise responsive and whether PGC-1α expression is associated with FNDC5 expression. The male subjects in the study performed single exercises: (1) 1 h low-intensity aerobic exercise (AE) (middle-aged, n = 17), (2) a heavy-intensity resistance exercise (RE) bout (young n = 10, older n = 11) (27 vs. 62 years), (3) long-term 21 weeks endurance exercise (EE) training alone (twice a week, middle-aged, n = 9), or …

Artrial Natriuretic Peptide Concentrations in Preeclampsia

1989

During pregnancy various humoral and functional mechanisms were recognized, that regulate the water and electrolyte household. In preeclampsia, increased water-sodium retention results from a variety of pathophysiological changes in the endocrinological system. There are also organ-specific changes, such as renal clearance reduction up to 30% in comparison to normal pregnancy. For many years, physiologists expected to find additional cardial mechanisms that influence homeostasis. In 1981, de Bold [3] identified ANP a new humoral factor that leads to increased water and sodium excretion. The influence of ANP in preeclampsia has been the subject of controversial discussion.

Agouti-related peptide-expressing neurons are mandatory for feeding.

2005

Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis.

Intrinsic changes on automatism, conduction, and refractoriness by exercise in isolated rabbit heart.

2001

We have studied the intrinsic modifications on myocardial automatism, conduction, and refractoriness produced by chronic exercise. Experiments were performed on isolated rabbit hearts. Trained animals were submitted to exercise on a treadmill. The parameters investigated were 1) R-R interval, noncorrected and corrected sinus node recovery time (SNRT) as automatism index; 2) sinoatrial conduction time; 3) Wenckebach cycle length (WCL) and retrograde WCL, as atrioventricular (A-V) and ventriculoatrial conduction index; and 4) effective and functional refractory periods of left ventricle, A-V node, and ventriculoatrial retrograde conduction system. Measurements were also performed on coronary…