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To acquire high-resolution T(1)-weighted images of the liver in rats, for which breath-holding cannot be ensured, respiratory triggering is essential. At the respiratory rate of 30-60 times/min in rats, however, T(1)-weighted images cannot be obtained with simple triggering. As a simple solution to this, we applied multiple repeated acquisitions with one trigger signal. With this technique, sufficient T(1) contrast could be easily achieved in rat liver enhanced by gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid infusion., (Copyright © 2012 Elsevier Inc. All rights reserved.)

To evaluate the usefulness of combination chemotherapy with cisplatin powder, which was newly designed for intra-arterial infusion (IA CALL) and lipiodol, for the VX 2 liver cancer model of the rabbit, sequential change of the plasma platinum concentration within the first 24 hours, as well as the tissue platinum concentration at 24 hours was measured after intra-arterial infusion of IA CALL. The infused materials were either IA CALL alone (C) or the combination of lipiodol+IA CALL (CL). In addition,the reduction rate of the VX 2 tumor was calculated among four therapeutic groups (C, CL, lipiodol alone (L), and saline alone (S)) after one week of intra-arterial infusion on the basis of 7.0 Tesla MR images. Total plasma platinum concentrations within the first 24 hours were kept low in group CL. No increase in the tissue platinum concentration in group CL was observed. On the other hand, the tumor reduction rate tended to be higher in group CL (group CL>group L=group C>group S). These results suggested that the intra-arterial infusion of IA CALL with lipiodol is more effective than that of IA CALL alone.

Background: Hepatic hypoxia during resuscitation and other critically ill conditions is a serious cause of acute hepatic failure. Measurement of the ATP concentration is a sensitive method to evaluate the extent of hypoxic damage in the liver. Hypothermia has been shown to attenuate organ injury in hypoxia. Our aim was to evaluate the effects of moderate hypothermia on the hepatic energy metabolism in rats during gradual hypoxia using (31)P nuclear magnetic resonance (NMR) spectroscopy., Materials and Methods: The rats were divided into two groups: a normothermia group (n = 8, rectal temperature at 37-37.5 degrees C) and a hypothermia group (n = 8, rectal temperature at 30-32 degrees C). The fraction of inhaled oxygen (F(I)O(2)) was reduced gradually (0.5, 0.2, 0.15, 0.125, 0.1, 1.0) and rectal temperature was regulated using a water perfusion mat under the rat body. Phosphoenergetic metabolism of the liver was evaluated from the changes in peak areas of beta-adenosine triphosphate (ATP) and inorganic phosphate (P(i)) in (31)P NMR spectra. Intracellular pH (pH(i)) was calculated from the chemical shifts between P(i) and alpha-ATP peaks., Results: In the normothermia group, beta-ATP decreased markedly and P(i) increased during hypoxia, while in the hypothermia group, both beta-ATP and P(i) changed only slightly from the initial state during hypoxia. During hypoxia, the minimal changes in beta-ATP were 18% and 80%, and the maximal changes in P(i) were 270% and 160% in the normothermia and hypothermia groups, respectively. Significant difference between the two groups was observed during hypoxia. The recoveries of beta-ATP and P(i) were more complete in the hypothermia group. The decrease in pH(i) during hypoxia was less in the hypothermia group., Conclusions: During gradual hypoxia, beta-ATP decreased, P(i) increased, and pH(i) decreased in the rat liver, depending on the oxygen concentration. These changes were more prominent in the NT group than in the HT group. We conclude that moderate hypothermia effectively protects high energy phosphoenergetic metabolites in rat liver during gradual hypoxia as compared to normothermia.

We report on a case of metastatic adenocarcinoma of liver that was removed and examined histochemically after microwave coagulation therapy (MCT). The patient was a 65-year-old woman who had a metastatic tumor in the liver (S3) after high anterior resection due to a rectal adenocarcinoma and received MCT against the tumor. One month after MCT, multiple metastatic tumors were detected by abdominal computed tomography (CT) scan. As it was difficult to control them by MCT alone, we performed lateral segmentectomy. To assess the effects of microwave ablation on cellular viability of metastatic tumor, we used enzyme histochemistry for acid phosphatase (AcP), which is positive in macrophages infiltrating in the tumor. In a part of the ablated area of resected liver, there was remaining neoplastic tissue of which the morphology was maintained in H&E staining. This was found to be microwave-fixed non-viable tissue because no enzyme activity of AcP was detected in the infiltrating macrophages. This case report suggests that enzyme histochemistry was useful to assess the effect of MCT, enabling us to distinguish fixed cells from viable cells.

The effects of ketamine and isoflurane on the phosphoenergetic state of the liver during haemorrhage were investigated using 31P nuclear magnetic resonance (NMR) spectroscopy. Male Wistar rats were anaesthetized with ketamine (1.0 mg kg-1 min-1 i.v., Ket 1.0 group, or 1.5 mg kg-1 min-1 i.v., Ket 1.5 group), or isoflurane 1.4% (Iso group). Haemorrhage was induced by withdrawing blood until the mean arterial pressure was reduced to 40 mm Hg, and this pressure level was then maintained for 45 min. Hepatic energy metabolism was evaluated from the changes in adenosine triphosphate (ATP) and inorganic phosphate (Pi). The beta-ATP decrease and the Pi increase were more marked in the two Ket groups than in the Iso group. At 20 min after haemorrhage, the beta-ATP peak areas were 34%, 32% and 76%, and the Pi peak areas were 257%, 260% and 160% of their initial values in the Ket 1.0, Ket 1.5 and Iso groups, respectively. NMR data were supported by chemical assessments. These results demonstrated that, in terms of phosphoenergetic levels, a continuous administration of 1.0 or 1.5 mg kg-1 min-1 ketamine markedly decreased hepatic metabolism during haemorrhagic shock, whereas inhalation of 1.4% isoflurane mitigates the metabolic damage.

Background: During endotoxemia, glucose and energy metabolism varies depending on the stage, severity, and other conditions. In this study, gluconeogenesis from 13C-labeled alanine and phosphoenergetic state in rat liver during the acute phase of endotoxemia were concurrently observed by in vivo 13C and 31P NMR spectroscopy in a noninvasive manner., Materials and Methods: Lipopolysaccharide from Escherichia coli (10 mg/kg) was injected intravenously followed by infusion of [3-13C]alanine. In vivo 13C and 31P NMR spectra were alternately collected for 90 min with a 2.0 Tesla CSI Omega System., Results: In our experimental model, endotoxin increased the pulse rate without decreasing the blood pressure and elevated the blood sugar level, which suggests the so-called hyperdynamic state. Even under such conditions, a slight, but significant, impairment of the phosphoenergetic state in the liver (a decrease in ATP and an increase in Pi) was detected with 31P NMR spectroscopy. The 13C peaks of glucose C6 and Glu/Gln C2 of the liver in endotoxemia were significantly lower than those of the control, despite hyperglycemia in endotoxemia., Conclusions: NMR spectroscopic studies suggest that the endotoxin caused the inhibition of gluconeogenic activity from the infused [3-13C]alanine and the TCA cycle accompanied by a deterioration in the phosphoenergetic state even in the hyperglycemic phase. Since the blood sugar level might be influenced by the systemic utilization of glucose, such direct measurements should prove important in the in vivo evaluation of glucose and energy metabolism in the liver.

We studied the effects of halothane versus isoflurane on the phosphoenergetic state and intracellular pH (pHi) of the rat liver using in vivo 31P nuclear magnetic resonance (NMR) spectroscopy during and after hemorrhagic shock. Seventeen rats were anesthetized with 1 minimum alveolar anesthetic concentration of halothane or isoflurane. The mean arterial blood pressure was reduced to 40 mm Hg and maintained at this level for 45 min by withdrawing blood from the common carotid artery. The shed blood was then returned slowly. In vivo 31P NMR spectra were consecutively collected throughout the study. The phosphoenergetic state of the liver was evaluated from the changes in adenosine triphosphate (ATP) and inorganic phosphate (P(i)) levels. pHi was calculated from the chemical shifts of P(i) and alpha-ATP peaks. During hemorrhagic shock, beta-ATP decreased to 35% and 45%, and P(i) increased to 300% and 230% of their initial values in the halothane and isoflurane groups, respectively. Intracellular acidosis was more severe in the halothane group. The recoveries of beta-ATP and P(i) were better in the isoflurane group. Halothane showed a more detrimental effect than isoflurane on the hepatic phosphoenergetic level during and after hemorrhagic shock.

The relationship between the phosphoenergetic state and gluconeogenesis in the liver after ischemic damage was investigated using living rats. The ATP level was determined with in vivo 31P nuclear magnetic resonance spectroscopy, and gluconeogenesis was evaluated with in vivo 31C NMR spectroscopy using L-[3-13C]alanine as a tracer. These two measurements were alternated repeatedly. The rats were divided into three groups: without ischemia (group A); with 10 min ischemia (group B); and with 30 min ischemia (group C). ATP was depleted to 20% of the preischemic state after 10 min ischemia and this level was maintained during 30 min ischemia. After reperfusion, the ATP level was partially restored, but the recovery was smaller in group C. Infusion of [3-13C]alanine was started immediately after the reperfusion. In vivo 13C NMR disclosed changes in the alanine C3, glutamine/glutamate C2 and C3, glucose C1-6, and glycogen C1 signals in the liver. After 60 min infusion of [3-13C]alanine, the ATP level correlated negatively with the signal intensity of alanine (r = -0.664, p = 0.008) and positively with those of glucose and glyogen (r = 0.586, p = 0.023, and r = 0.643, p = 0.011, respectively). These results suggest that the ATP level participates in gluconeogenesis and glycogenesis in the liver. Such multinuclear in vivo NMR observations might uncover new aspects of the metabolic function of the liver in the in vivo state.

Glucose and energy metabolism in rat liver after ischemic damage was investigated by in vivo 31P NMR spectroscopy, 1H-detected 13C NMR spectroscopy, and in vitro 13C NMR spectroscopy using [1-13C]glucose as a tracer. Arterial ketone body ratio (AKBR; acetoacetate/beta-hydroxybutylate) and oxygen consumption of isolated mitochondria were also examined to evaluate hepatic function. The rats were divided into three groups: (A) without ischemia, (B) 10-min ischemia, and (C) 30-min ischemia. ATP was almost depleted at 10 min of ischemia and recovered after reperfusion, but the recovery was not complete. The recovery after 30-min ischemia was smaller than that after 10-min ischemia. [13C]Glucose was infused immediately after the reperfusion, and in vivo 1H-detected 13C NMR demonstrated sequential glucose incorporation into the liver. However, the incorporation depended on the blood sugar levels and did not reflect hepatic function. In vitro 13C NMR disclosed the glycogen C-1 signal in the nonischemic group and alanine C-3 and lactate C-3 signals in the ischemic groups. The intensity of glycogen was correlated positively (r = 0.648, P = 0.002) and those of alanine and lactate were correlated negatively (r = -0.831, P < 0.005 and r = -0.710, P = 0.005, respectively) to the ATP levels as measured by in vivo 31P NMR. These results suggested that ATP level participates in glycogenesis and gluconeogenesis in the liver. The AKBR and oxygen consumption of isolated mitochondria were the highest in the 10-min ischemia group, which might reflect mitochondrial compensatory response to the decreased ATP level.

The activities of cathepsin B, L, J and H in rat liver were significantly increased by starvation if compared with normal diet rats. Furthermore, the activity of cathepsin L increased with glucagon treatment, and the activities of cathepsin L and H decreased significantly with insulin treatment. The changes in cathepsin B and J activities showed the same tendencies as those of cathepsin L and H, but the differences were not statistically significant. The changes in the activities of cathepsin B and L on starvation corresponded with the changes of enzyme protein amounts judged from Western blotting analysis. The levels of the lysosomal cysteine proteinases and amino acid deaminases in the liver changed in parallel with the hormonal and dietary conditions. The increases of alanine amino transferase activity (AAT) started from a much earlier stage than those of cathepsins under the starvation condition. Although administration of prednisolone caused marked induction of the deamination enzymes such as AAT, the levels of cathepsins in the liver were not changed.

The cytoprotective effect of prostaglandins (PG) was evaluated by in vivo 31P MR spectroscopy. Twenty rabbits were divided into two groups; the control group given physiological saline, and the PG group given prostaglandin E1 (0.5 microgram/kg/min). Each solution was infused for 8 min, after which complete hepatic ischemia was induced for 20 min, followed by reperfusion for 40 min. During ischemia, beta-ATP decreased to 23.6% and 42.3%, phosphomonoester increased to 260% and 200% of their initial values in the control and the PG groups, respectively. Inorganic phosphate also increased. After reperfusion, beta-ATP recovered to 65.2% and 96.5%, phosphomonoester to 130% and 110%, inorganic phosphate to 140% and 120% in the control and PG groups, respectively. The changes during ischemia were significantly smaller and the recoveries during reperfusion were more complete in the PG group. These results may confirm the cytoprotective effect of prostaglandins by in vivo 31P-MR spectroscopy.

Phosphorus-31 NMR spectra in rabbit liver were successively observed for more than 5 months in a chronic CCl4 intoxication model using implanted wireless surface coils. The quality of the obtained NMR spectra was satisfactory and there was sufficient time resolution to follow the dynamic changes that occurred during a fructose tolerance test. The implanted coil did not lead to any serious adverse effects such as infection or liver dysfunction. During an 18-week administration of CCl4, the area of the phosphodiester peak significantly decreased. The ratio of P(i)/beta-ATP was transiently elevated and gradually returned to the control level. In the fructose tolerance test, the increase in phosphomonoester and the decrease in P(i) and beta-ATP after i.v. fructose loading were apparent, but the degrees in these changes became smaller during the CCl4 intoxication. This wireless surface coil was useful for consecutive and non-invasive 31P NMR observations of the liver to follow chronically treated animal models over a period of several months.

Hypothermically preserved rat livers were studied with proton magnetic resonance imaging (1H-MRI) under proton density-, spin-lattice relaxation time-, spin-spin relaxation time- and diffusion-weighted (P-W, T1-W, T2-W and D-W) conditions. Relative signal intensities (RSI) of the liver to distilled water in terms of P-W, T1-W, T2-W and D-W increased time-dependently during 12 h hypothermic (4 degrees C) preservation with saline, while these parameters did not increase during preservation with University of Wisconsin (UW) solution. One-hour Wiggers' hypotensive treatment before the harvesting increased the RSIs of P-W, T2-W and D-W, and the subsequent 12-hour preservation with UW solution did not improve the increased RSIs. These results suggest that 1H-MRI has potential application in evaluating the biophysical changes of water molecules in the liver graft, which were measured by placing the harvested liver in a plastic bag under a magnetic field at a low temperature.

Changes in lipoprotein metabolism after liver transplantation from living related donors were investigated in nine pediatric patients by means of biochemical and proton nuclear magnetic resonance (NMR) analyses of lipoprotein. NMR offers rapid and nondestructive measurement of lipoprotein. The ratio of esterified cholesterol to total cholesterol, expected to be a prognostic indicator after liver transplantation, was low before the operation (0.44) and recovered to over 0.6 at 3 weeks. The half line width of the methylene peak of lipoprotein, as measured by proton NMR, was correlated with the ratio of esterified cholesterol to total cholesterol. It is suggested that proton NMR analysis can provide information about the biophysical changes in lipoprotein associated with liver transplantation.

The energy metabolism of the heart and the liver was assessed in brain-dead dogs by 31P nuclear magnetic resonance spectroscopy. The mean blood pressure and pulse rate changed respectively from 136.1 +/- 9.3 mm Hg (mean +/- SEM) and 126.7 +/- 4.4/min in the control period, to 212.9 +/- 15.8 mm Hg and 146.7 +/- 13.3/min during Cushing phenomenon (CU period), and to 60.0 +/- 6.4 mm Hg and 60.0 +/- 2.9/min after completion of brain death (BD period). The ratio of creatine phosphate to inorganic phosphate (PCr/Pi) of the heart decreased from 5.00 +/- 1.08 to 3.24 +/- 0.80 in the CU period and increased to the levels of the control values in the early BD period. The intracellular pH of the heart decreased from 7.20 +/- 0.07 to 6.91 +/- 0.02 in the CU period and increased to 7.12 +/- 0.01 in the BD period. The positive relationship between the Pi/PCr and the rate-pressure product (BP x PR) indicates that the regulation of the oxidative metabolism by free ADP was well maintained except at some points in the CU period (Pi/PCr = 8.77 x 10(-6) BP x PR + 0.164, r = 0.704). This suggested that the remarkable hypotension and bradycardia in the BD period is not associated with cardiac energy failure. Although the energy states of both the heart and the liver in brain-dead dogs were adequately maintained in the BD period, the changes were different.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic blood flow (HBF) and energy metabolism during moderate hypotension induced by prostaglandin E1 (PGE1) and nicardipine were studied by in vivo magnetic resonance spectroscopy. HBF was determined by the deuterated water clearance method by using deuterium magnetic resonance spectroscopy, and energy metabolism was estimated from the changes in the levels of adenosine triphosphate and inorganic phosphate by using phosphorus (31P) magnetic resonance spectroscopy. Mean arterial blood pressure was intentionally reduced to 60% of control with PGE1 (n = 5) or nicardipine (n = 5). The HBF decreased by 38% and by 50% during the hypotension induced by PGE1 and nicardipine, respectively. The level of adenosine triphosphate decreased by 12% and that of inorganic phosphate increased by 80% during nicardipine-induced hypotension, whereas the corresponding levels showed no remarkable changes during PGE1-induced hypotension. After the cessation of drug administration, mean arterial blood pressure and HBF recovered to the control levels in the PGE1 group, but not completely in the nicardipine group. In the latter group, the level of inorganic phosphate did not recover either. These results indicate that during hypotension induced with PGE1 hepatic circulation and metabolism are conserved to a greater extent than during hypotension induced with nicardipine.

For the assessment of 31P-NMR spectroscopic data, phospholipid precursors (phosphorylethanolamine (PE) and phosphocholine) and catabolites (glycerophosphorylethanolamine (GPE) and glycerophosphorylcholine (GPC)), as well as adenosine phosphates were chemically determined in regenerating rat liver. The data were compared with those obtained by in vivo and in vitro 31P-NMR spectroscopies. Chemical assay revealed a significant increase of PE and a decrease of GPE, GPC and ATP in hepatectomy group compared to sham operation group. The values obtained by in vitro NMR were in good agreements with those of chemical assay, but significant differences between the two groups were observed only in PE and inorganic phosphate (Pi). Noticeable increase in PME was not detected by in vivo 31P-NMR spectroscopy, although the increase of PE was about 2.5-times that of the control and its constitution ratio to the whole phosphomonoester (PME) was less than 15%. On the other hand, in vivo NMR showed a large phosphodiester (PDE) peak occupying approx. 40% of the total phosphorus signal, while the contribution of its constituents, GPE and GPC was about 5% found by both chemical assay and in vitro NMR. The PDE peak in in vivo NMR seemed to reflect the membrane phospholipid itself rather than its catabolites. A slight decrease of phosphoenergetic level in regenerating rat-liver was commonly suggested by all three analytical methods.

The changes in hepatic energy state were assessed by 31P-nuclear magnetic resonance spectroscopy (31P-MRS) and arterial ketone body ratio (AKBR) in brain dead dogs. 31P-MRS and AKBR were measured before and at 3 hours after brain death. Wiggers' shock model was employed to compare the energy metabolism during hypotension. 1) The brain death model: Systemic blood pressure changed from 178.3/115.0 mmHg (mean) in the control period, to 259.5/162.5 mmHg during Cushing phenomenon (CU period) and to 63.3/51.7 mmHg after completion of brain death (BD period). beta-ATP/Pi increased from 1.27 +/- 0.14 (mean +/- SEM) to 1.46 +/- 0.16 in the early CU period, and then decreased to 1.11 +/- 0.15 at 60 minutes after BD, followed by a gradual increase to 1.33 +/- 0.13 at 3 hours after BD. Intracellular pH (pHi) increased alkaline to the control value. AKBR decreased from 1.10 +/- 0.26 to 0.46 +/- 0.15 in the CU period (p less than 0.05) and then increased to 1.48 +/- 0.25 after BD. 2) Wiggers' shock model: Systemic blood pressure was 190.0/112.5 mmHg in the control period, 83.8/51.3 mmHg during exsanguination (EX period) and 185.0/117.0 mmHg after retransfusion (RT period). beta-ATP/Pi decreased from 1.17 +/- 0.13 to 0.61 +/- 0.10 in the EX period (p less than 0.05) and increased to 1.37 +/- 0.08 in the RT period. The pHi deviated from 7.33 +/- 0.07 to 6.82 +/- 0.14 in the EX period (p less than 0.01) and to 7.51 +/- 0.21 in the RT period. AKBR decreased from 1.00 +/- 0.11 to 0.21 +/- 0.04 in the EX period and increased to 1.08 +/- 0.12 in the RT period. The energy metabolism of the liver was well maintained in the state of brain death in spite of remarkable hypotension, although that was not the case with Wiggers' shock model. It was suggested that the combination of 31P-MRS and AKBR was useful for the evaluation of graft liver viability.