PubMed Health⌕ Search

Biomedical subjects

T Obata

Publications and source records attributed to T Obata.

At least 235 records · Page 13Linked to original sources

Intrahepatic cholestasis and hyperbilirubinemia in ethynyl estradiol and chlorpromazine-treated rats.

Intrahepatic cholestasis associated with hyperbilirubinemia was induced by the simultaneous administration of ethynyl estradiol (EE) and chlorpromazine hydrochloride (CPZ) for 7 days to female Sprague-Dawley rats. Increases in direct serum bilirubin levels and alkaline phosphatase activities were observed concomitantly with diminished bile flow and bile acid excretion. However, the bilirubin output in the bile remained unchanged. [14C]Erythritol clearance decreased in parallel with the diminished bile flow, while [14C]sucrose biliary clearance increased, suggesting that the decrease in bile flow was of canalicular origin and also due to increased permeability in the biliary tract. There was a prominent decrease in the bile acid-independent flow, and the bile acid-dependent flow also decreased concomitantly with the diminished bile acid excretion. Slight increases in cytochrome P-450 and anilin hydroxylase activities in liver microsomes were observed, and bilirubin UDP-glucuronyl transferase activity increased significantly. Indirect bilirubin clearances determined by a bilirubin load test were markedly reduced in the icteric rats. The bilirubin load test also suggested that bilirubin flowed back into the circulating blood and that gluculonidation of bilirubin mono-gluculonide (BMG) to bilirubin diglucuronide (BDG) was impaired. Light microscopic examinations of the liver revealed marked proliferation of the bile ductules and numerous vacuoles in the hepatocytes. Dilatation of the bile canaliculi with diminished microvilli was also detected by scanning electron microscopy.

Animals↗

Brain tyrosine hydroxylase activity and calculated amount of brain dopa synthesized in carbon tetrachloride-intoxicated rats.

Tyrosine hydroxylase activity in the corpus striatum was measured in a large dose of carbon tetrachloride (CC14)-intoxicated rats in order to confirm whether brain catecholamine contents decrease in acute hepatic failure or not. Theoretical amounts of dopa synthesized in the brain of the treated animals were calculated according to an equation of enzyme kinetics. Tyrosine hydroxylase activities in CCl4-injured rats were similar to those in control rats, and calculated amounts of brain dopa in liver-injured rats were rather higher as compared to those in untreated animals.

Amino Acids↗

A simple and rapid method for determining blood ammonia levels.

Blood ammonia levels in patients with various liver diseases were determined quantitatively by a simple and rapid method using the Amitest Meter System. The results were compared to those obtained by an enzymatic method and were well correlated. This simple Amitest is also useful in animal experiments, particularly when there is a need to determine blood ammonia levels serially. This paper test was evaluated as being accurate and reliable for clinical and experimental use.

Ammonia↗

ONO-3144, a new anti-inflammatory drug and its possible mechanism of action.

Anti-inflammatory activities of ONO-3144 have been studied in various experimental models. This compound showed an inhibitory effect on increased vascular permeability and acute inflammation. In the carrageenin test the activity of ONO-3144 was comparable to that of indomethacin (IM), while in the dextran, albumin, yeast and scald edema test it was more potent than that of IM. Unlike IM, phenylbutazone (PB) and tiaramide (TI), ONO-3144 showed marked inhibitory effects on H2O2-induced hemolysis and lipid peroxidation. In the prostaglandin (PG) biosynthesis series, ONO-3144 did not inhibit cyclooxygenase activity but stimulated PG hydroperoxidase activity, facilitated conversion to PGH2 and also inhibited thromboxane (Tx) synthetase. The findings suggest that ONO-3144 is potentially a new type of anti-inflammatory drug. Possible sites of action of ONO-3144 are discussed.

Animals↗

Characteristics change in serum amino acid levels in different types of hepatic encephalopathy.

Serum amino acid patterns in patients with different types of hepatic encephalopathy were investigated. Marked elevations in most of serum amino acids observed in untreated patients with acute type of fulminant hepatitis were not remarkable in the patients who have already treated; particularly branched chain amino acids (BCAA), phenylalanine and tyrosine were much lower in the latter group. However, elevation of serum methionine levels and lower ratio of BCAA/(phenylalanine + tyrosine) were similarly observed in both groups. In encephalopathic patients with decompensated cirrhosis, many amino acids such as phenylalanine, tyrosine and methionine were elevated with a slight depressed levels of serum BCAA. Highly significant decrease in serum BCAA levels and no elevation of phenylalanine and methionine with a minimal increase of tyrosine were observed in patients with chronic type of hepatic encephalopathy; other amino acids except for glutamine and arginine were much lower as compared to those in decompensated cirrhotics and even to the control values.

Adolescent↗

Effects of intraduodenal feeding of a branched-chain amino acid-rich solution on ammonia-induced encephalopathy in liver-injured rats.

A preventive effect of intraduodenal prefeeding of a branched-chain amino acid (BCAA)-rich solution on ammonia-induced encephalopathy was investigated with carbon tetrachloride CC14-injured rats with the elevated levels of blood ammonia. Five out of six cirrhotic rats, to which an electrolyte solution alone was preinfused for 24 hours, fell into coma following ammonia acetate injection and two comatose rats died. However, no cirrhotic rats preinfused with a BCAA-rich solution died and only two out of the six showed coma with complete recovery. The similar preventive effect could not be observed in rats with acute liver injury.

Acetates↗

Effects of insulin and glucagon on serum amino acid concentrations in liver disease.

The effects of insulin and glucagon administration on serum amino acid levels were investigated in patients with severe liver disease, since simultaneous injection of pancreatic hormones has been recently introduced as a therapeutic approach. The changes in serum amino acid concentrations, as observed 3 h after ceasing a 3 h infusion of insulin and glucagon in 500 ml glucose solution, were an elevation of serum branched chain amino acid (BACA) levels and of the molar ratio of BCAA/aromatic amino acid (AAA) levels in patients with liver cirrhosis. Similar increases of serum BCAA levels during the infusion were also observed in patients with fulminant hepatitis. The results suggest that insulin-glucagon therapy for severe liver disease has no harmful side effects at least with respect to alterations in the serum aminogram.

Amino Acids↗

[Clinical evaluation of pivmecillinam in the maintenance therapy of chronic urinary tract infection (author's transl)].

In order to evaluate the efficacy and safety of pivmecillinam (melysin tablet, PMPC), PMPC was administered to 78 chronic UTI cases in the field of obstetrics and gynecology (posthysterectomy infection, chronic cystitis, chronic pyelonephritis and etc.). In principle, daily 400 mg of PMPC was administered for 2 weeks. (1) Overall clinical efficacy judged by doctor was evaluated in 78 cases and the result was; excellent in 17, good in 37, fair in 10, poor in 13 and unknown in 1 case with the effectiveness rate of 69.2%. (2) Overall clinical efficacy judged by 'criteria for clinical evaluation in complicated UTI' recommended by UTI study member was evaluated in 54 cases and the result was; excellent in 15, good in 20 and poor in 19 cases with the overall efficacy rate of 64.8%, the result of which was similar to that of doctor's judgement. (3) Efficacy on pyuria was evaluated in 72 cases and it was cleared in 27, decreased in 25, unchanged in 20 and unknown in 6 cases. Efficacy on bacteriuria was evaluated in 72 cases and it was eliminated in 44, decreased in 9, replaced in 8, unchanged in 8 and unknown in 9 cases. (4) Side effect, considered by doctors to be caused by PMPC administration, was noticed in 3 out of 78 cases (3.8%), all of which was mild gastrointestinal disturbance and the administration of PMPC was continued. Abnormal change of laboratory finding considered by doctors to be caused by PMPC administration was noticed in 1 out of 78 cases, which was slight elevation of GOT and GPT values. It is therefore considered that PMPC appear to be useful drug for the maintenance therapy of chronic UTI in the field of obstetrics and gynecology.

Adult↗

[Effects of 16,16-dimethyl-trans-delta 2-PGE1 methyl ester (ONO-802) on uterine motility (author's transl)].

In rats on day 20 of pregnancy, ONO-802 exerted a uterine contractile effect when 0.2 microgram/kg was given i.v. and also with an intrauterine administration of 0.5 ng, s.c. administration of 1 microgram/kg and vaginal administration of 10 microgram/kg. The contractile activity of ONO-802 was 100-1000 times more potent than that of PGE2 alpha and was long-acting. Intravenous PGE1 or PGE2 induced a transient contraction followed by inhibition of spontaneous uterine motility in nonpregnant rats and in those with an early pregnancy. In nonpregnant hamsters, a relaxation was seen. ONO-802, similar to PGF2 alpha, showed a contractile effect regardless of states of nonpregnancy and pregnancy, both rats and hamsters. IN rats, a contractile threshold dose of ONO-802 was similar from day 15 to day 21 of pregnancy. Oxytocin produced an acute decrease in this threshold dose on phentolamine or methysergide, but was inhibited by papaverine, dibutyryl cAMP, salbutamol and verapamil. These results suggest that uterine contraction induced by ONO-802 differs from the contractions induced by PGE1, PGE2, and oxytocin, that ONO-802 does not induce endogenous PGs, and that the effect of ONO-802 is not mediated by the autonomic nervous system.

Alprostadil↗