decarboxylase/hypoxia

Histidine decarboxylase (HDC) catalyzes the formation of histamine from histidine. Histamine has various effects in physiological and pathological reactions, such as inflammation, cell growth, and neuro-transmission. We investigated the role of hypoxia-inducible factor (HIF)-1 on hypoxia-induced HDC

Objective To study the developmental changes of glutamic acid decarboxylase-67 (GAD-67, a GABA synthetic enzyme) in normal and hypoxic ischemic (HI) brain. Methods C57/BL6 mice on postnatal day (P) 5, 9, 21and 60, corresponding developmentally to premature, term, juvenile and adult human brain were

In rat lung and cultured lung vascular cells, hypoxia decreases ornithine decarboxylase (ODC) activity and increases polyamine import. In this study, we used rat cultured pulmonary artery endothelial cells to explore the mechanism of hypoxia-induced reduction in ODC activity and determined whether

The cellular responses to hypoxia are poorly understood. To test the hypothesis that ornithine decarboxylase (ODC; L-ornithine carboxy-lyase; EC 4.1.1.17) activity and polyamine concentrations change in response to acute hypoxia, we performed the following studies. Pregnant Sprague-Dawley rats

Although glucocorticoids are widely used to stimulate fetal/neonatal lung function, they also interfere with cellular development in the central nervous system. Dexamethasone was administered to pregnant rats in late gestation at a dose (0.8 mg/kg) that lies just above the threshold for stimulation

Ornithine decarboxylase activity (ODC; E.C. 4.1.1.17), is significantly elevated in fetal and newborn rat brain in response to acute hypoxia. Because relatively little is known about ODC activities and polyamine metabolism in hypoxia and also because ODC and the polyamines are essential for normal

Recent studies in vivo have demonstrated that ornithine decarboxylase (ODC) activity in the fetal rat brain is elevated 4-5-fold by acute maternal hypoxia. This hypoxic-associated increase is seen in the rat brain in both the newborn and the adult. Because of the intimate involvement of ODC in

In fetal as well as newborn rats, acute hypoxic exposure results in significantly elevated brain ornithine decarboxylase (ODC) activity, polyamine concentrations, and ODC mRNA. The interpretations of these in vivo hypoxic-induced changes, however, are complicated by maternal confounding effects. To

A former study indicated that hypoxic-ischemic encephalopathy in rat sustained during early postnatal life may result in permanent epileptic activity in the baseline electroencephalogram. We, therefore, investigated whether the presumed higher firing frequency and metabolic activity of neurons in

The immature brain is resistant to cell damage from hypoxia, such as that experienced during parturition. Because cocaine causes cerebral ischemia, we examined whether cocaine interferes with this resistance. On postnatal days 1, 4 or 8, neonatal rats were given an acute injection of saline or

Intermittent hypoxia (IH) associated with sleep apnea leads to cardio-respiratory morbidities. Previous studies have shown that IH alters the synthesis of neurotransmitters including catecholamines and neuropeptides in brainstem regions associated with regulation of cardio-respiratory functions.

BACKGROUND Chronic hypoxia-induced pulmonary hypertension and vascular remodeling have been shown to be associated with ornithine decarboxylase 1 (ODC1). However, few animal studies have investigated the role of ODC1 in acute hypoxia. OBJECTIVE We investigated ODC1 gene expression, morphologic and

The polyamines are a family of low-molecular-weight organic cations that play essential intracellular regulatory roles in cell growth and differentiation. Elevations in cellular polyamine contents necessary for most physiological and pathological events in the lung appear to be driven by increase de

We have shown that there is a highly significant difference between right and left ventricular ornithine decarboxylase activity. The left ventricle had a much higher activity compared with the right ventricle. A restricted diet caused a decrease in ornithine decarboxylase activity after 24 hr.

In response to acute maternal hypoxia, ornithine decarboxylase (ODC) activity increased significantly in fetal rat brain, peaking at 4 h. This was associated with increased ODC mRNA and elevated polyamine concentrations. To correlate this response with development, we measured ODC activity in the