[Kyotorphin like substance in human cerebrospinal fluid of patients with persistent pain]

Kyotorphin is an analgesic neuropeptide isolated from the bovine brain in 1979. Further studies showed that kyotorphin produces an analgesia through an increased release of met-enkephalin in the brain and the spinal cord. We showed that it is also found in the human cerebrospinal fluid and the concentrations of kyotorphin in normal human CSF is 1.19 +/- 0.51 pmol.ml-1. We also found that it is lower in patients with persistent pain (0.24 +/- 0.04 pmol.ml-1). Above results suggest that kyotorphin acts as a putative neuromediator and/or an endogenous pain modulator in the human brain.

A GM1b-derived disialoganglioside GD1c is the predominant ganglioside of rat thymocytes

The thin-layer chromatographic (TLC) pattern of gangliosides of rat thymocytes showed a profile characterized by the occurrence of a predominant ganglioside which did not correspond to any reference gangliosides of rat brain. The ganglioside was isolated from rat thymus, and characterized by compositional analysis, methylation analysis, sialidase treatment, negative-ion fast atom bombardment (FAB) mass spectrometry, and proton NMR spectroscopy. The structure was elucidated to be NeuGc alpha 2-8NeuGc alpha 2-3Gal beta 1-3GalNac beta 1-4Gal beta 1-4Glc beta 1-1Cer. This is the major ganglioside of rat thymus lymphoid cells and is one of the GM1b-derived gangliosides, GD1c, having two N-glycolylneuraminic acids. This is the first report on the occurrence of GD1c in normal animal cells.

Definition of total biosynthesis pathway of taurolipids in Tetrahymena cells

Taurine-combined fatty acids were found in the lipotaurine fraction of cells of Tetrahymena thermophila. Taurine and fatty acid moieties of the compounds were identified by nuclear magnetic resonance and gas chromatography-mass spectrometry, respectively. The molar ratio of fatty acid methyl esters and taurine in the hydrolysate of the lipotaurine fraction by methanolic hydrochloric acid hydrolysis, was 1.06:1.00. From the results, the structures of six taurine-combined fatty acids including lipotaurine in the fraction were identified. These structures suggest that the compounds are precursors of lipotaurine as an intermediate of taurolipids biosynthesis, and lipotaurine is biosynthesized via 2-(octadecanoylamino)ethanesulfonic acid and 2-(7-hydroxy-13-octadecenoylamino)ethanesulfonic acid. From the results of the present study and our previous studies, the total biosynthesis pathway of taurolipids is defined.

Species-specific antibodies of Tetrahymena acid alpha-glucosidase

1. Tetrahymena acid alpha-glucosidases A and B were purified from T. pyriformis W and T. thermophila 399, respectively. The acid alpha-glucosidases A and B were different in immunological properties and thermostability. 2. The acid alpha-glucosidases A and B reflected specific distribution between T. pyriformis and T. thermophila. 3. Type A and B of taurolipid showed a species-specific distribution pattern between T. pyriformis and T. thermophila.

A unique fucoganglioside with blood group B determinant in rat spleen

A unique fucoganglioside was isolated from rat spleen and characterized by compositional analysis, methylation analysis, exoglycosidase treatment, negative ion fast atom bombardment (FAB) mass spectrometry, and proton NMR spectrometry. The ganglioside was identified as alpha Gal,Fuc-GM1(NeuGc), which has the blood group B determinant at the nonreducing termini, as shown below: (formula; see text) This is the first report describing the occurrence in nature of alpha Gal,Fuc-GM1 containing N-glycolylneuraminic acid.

Identification of novel gangliosides containing lactosaminyl-GM1 structure from rat spleen

Two novel monosialogangliosides were isolated from rat spleen. The structures of the gangliosides (shown below, where NeuNGc is N-glycolylneuraminic acid) were characterized by compositional analysis, methylation analysis, hydrolyses with exoglycosidases, direct probe fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectrometry. A novel structure common to both gangliosides was N-acetyllactosaminyl-GM1 LacN-GM1; where GM1 is II3NeuAc-GgOse4Cer), and this is the first paper to report the occurrence of a new group of gangliosides. [formula: see text] Furthermore, in a monosialoganglioside fraction of rat spleen, the occurrence of a ganglioside having two lactosamine units (Gal alpha 1-3(Gal beta 1-4GlcNAc beta 1-3)2-GM1(NeuAc) (alpha Gal-(LacN)2-GM1] was suggested. These gangliosides have a unique structure, which includes the ganglio series ganglioside core and the extended modification characteristic of the lacto series.

2-(7,13-Dihydroxy-2-trans-octadecenoylamino)ethanesulfonic acid (lipotaurine) as an intermediate of taurolipids biosynthesis

A hydroxy fatty-acid-combined taurine (lipotaurine) was found in the taurolipids fraction of Tetrahymena thermophila. Lipotaurine accounted for about 1.4% of the total taurolipids of the cells, and was composed of taurine and 7,13-dihydroxy-2-trans-octadecenoic acid. By nuclear magnetic resonance, mass and infrared spectrometries, the chemical structure of lipotaurine was identified as 2-(7,13-dihydroxy-2-trans-octadecenoylamino)ethanesulfonic acid. When cells of T. thermophila were incubated with the double-labeled lipotaurine which was biosynthesized from [2(n)-3H]taurine and [1-14C]stearic acid, both the radioactivities were detected in taurolipid A, B and C. Furthermore, the ratio of the radioactivities of 3H and 14C in the lysotaurolipids were the same as that of the lipotaurine. From these results, it is suggested that lipotaurine is an intermediate of taurolipid biosynthesis.

Identification of pentahydroxystearic acid-containing taurolipid (taurolipid C) isolated from Tetrahymena thermophila

A pentahydroxystearic acid-containing taurolipid (taurolipid C) was found in cells of Tetrahymena thermophila. The lipid accounted for about 1.2% of the total taurolipids of the cells. The lipid was subjected to mild alkaline and methanolic hydrochloric acid hydrolyses, and the structures of the hydrolyses products were identified by mass and nuclear magnetic resonance spectrometries, as taurine, non-hydroxy fatty acid and 2,3,7,12,13-pentahydroxystearic acd, a novel fatty acid. The NMR spectra of the intact and acetylated lipid showed that the carboxyl group of the pentahydrxyostearic acid was combined with the amino group of taurine, and the hydroxy group at C-3 was esterified with non-hydroxy fatty acids. From these results, the pentahydroxystearic acid-containing taurolipid (taurolipid C) isolated from T. thermophila was identified as 2-(3-acyloxy-2,7,12,13-tetrahydroxyoctadecanoylamino)ethanesulf oni c acid.

[A simple method of extracorporeal membrane oxygenation (ECMO)--3. The effects of pumpless ECMO (arterio-venous shunt) on arterial blood gas measured for 24 hours]

In eight anesthetized mongrel dogs, the pumpless ECMO applied between the femoral artery and vein was performed under the condition of hypoventilation for 24 hours. The methods were same as the first and second reports, except the pumpless ECMO was used. The abnormal parameters in the cardiovascular and respiratory system (blood gas analysis and end expiratory gas analysis), induced by hypoventilation, recovered to almost normal ranges, by operation of the pumpless ECMO for 24 hours. The pumpless ECMO might have such advantages over ECMO with pump as the less destruction of blood cell, easy performance and simple apparatus. In conclusion, pumpless ECMO using arterio-venous shunt may be applied clinically on respiratory distress conditions.

[A simple method of extracorporeal membrane oxygenation (ECMO)--2: The effects of ECMO (arterio-venous shunt) on the arterial blood gases measured for 24 hours]

In eight anesthetized mongrel dogs with thiopental, diazepam and pancuronium bromide, ECMO with arterio-venous shunt was performed under hypoventilation for 24 hours. The blood flow through the ECMO which was connected between the femoral artery and vein was approximately 40% of the cardiac output. Hypoventilation was induced to decrease PaO2 to around 40mmHg and increase PaCO2 to around 80 mmHg. The ECMO improved the abnormal parameters, which were induced by the hypoventilation, to almost normal range (PaO2 80mmHg, PaCO2 30mmHg) for 24 hours. Furthermore, there were no abnormalities in cardiovascular and other systems during ECMO.

[A study of the leucine enkephalin like substance and enkephalin degrading enzyme activity in human cerebrospinal fluid]

Leucine enkephalin like substance (Leu-Enk) and enkephalin degrading enzyme activity (EDEA) in cerebrospinal fluid (CSF) of three patients suffering from pain were measured. As compared with control values before treatments, the values of Leu-Enk in CSF decreased, and those of EDEA increased in all the patients. After the treatment, two patients were fortunately cured of pain, and their two values returned to normal. But the other patient could not recover from severe pain, and their values remained abnormal. It is concluded that Leu-Enk and enkephalin degrading enzyme in CSF may play an important role in regulation of pain sensitivity.

Protection of endogenous enkephalin degradation from peptidases in human serum by actinonin

This paper describes a new method for detecting the endogenous enkephalin level in human serum without interference from serum peptidases and contaminating proteins. The method consists of a combination of addition of a peptidase inhibitor, actinonin to serum and dialysis. The activity of enkephalin degrading enzymes was completely abolished by actinonin. Furthermore, contaminating proteins which interfered with RIA assay of enkephalins were removed by the dialysis process. This combination process enabled precise detection of the concentration of enkephalin-like substances in human serum. The mean normal serum level of leucine-enkephalin assayed by this method in 12 healthy volunteers was 93.4 pg/ml.

Isolation and structural characterization of a diacyltaurolipid in cells of Tetrahymena mimbres

A diacyltaurolipid was found in cells of Tetrahymena mimbres (formerly Tetrahymenas pyriformis NT-1). The lipid accounted for about 0.05% of the total lipids of the cells, and was composed of taurine (1 equiv.), 3,7,13-trihydroxystearic acid (1 equiv.) and non-hydroxy fatty acids (2 equiv.). By mild alkaline hydrolysis, non-hydroxy fatty acids (2 equiv.) and 2-(3,7,13-trihydroxyoctadecanoyl)aminoethanesulfonic acid were obtained. For determination of the positions of the ester bonds of the lipid, the free hydroxy group of the intact lipid was converted to a ketone, and the esterified hydroxy groups were acetylated after methanolic hydrochloric acid hydrolysis. By mass and nuclear magnetic resonance spectrometry, the structure of the derivative was identified as methyl 3,7-diacetoxy-13-oxooctadecanoate. From these results, the diacyltaurolipid isolated from T. mimbres was identified as 2-(3,7-diacyloxy-13-hydroxyoctadecanoyl)aminoethanesulfonic acid (7-acyltaurolipid A). This structure suggests that the diacyltaurolipid may be formed by acylation of taurolipid A.

Inhibitory effect of taurolipids on Clostridium perfringens sialidase

Taurolipids A and B, which are detergent-type compounds isolated from protozoan Tetrahymena cells, were demonstrated to inhibit strongly the activity of Clostridium perfringens sialidase. On addition of 280 pmol of taurolipid B to 20 mU of the enzyme, the sialidase activity was decreased to 7% of the original activity at pH 5.1 as the optimum pH. The inhibition was non-competitive. Effective inhibition was observed at the acidic region from the isoelectric point of the sialidase, and at a low ionic strength. Both the long chain acyl and sulfonic acid groups of taurolipids were required for the inhibition of the sialidase activity. A mechanism is postulated for the inhibition.

Pathway of taurolipid B formation from exogenous taurolipid A by Tetrahymena thermophila

When Tetrahymena thermophila was incubated with taurolipid A isolated from T. pyriformis NT-1, the exogenously added taurolipid A was deacylated rapidly, and taurolipid B content in the cells was increased. The deacylated taurolipid A (lysotaurolipid A) content reached a maximum early on during incubation, and then declined. Taurolipid B and lysotaurolipid B contents in the cells were increased continuously during the incubation. These observations suggest that lysotaurolipid A was an intermediate for taurolipid B formation. When cells were incubated with lysotaurolipid A, newly formed lysotaurolipid B and taurolipid B were observed. Furthermore, when cells were incubated with lysotaurolipid B, only taurolipid B was newly formed. In contrast, newly formed lysotaurolipid B was observed when cells were incubated with exogenous taurolipid B. From the results, we have postulated the biosynthetic pathway of taurolipid B from exogenous taurolipid A in cells of Thermophila.

Effect of di-n-octyl phthalate on fatty acid composition of phosphatidylcholine in Tetrahymena

We examined the effect of di-n-octyl phthalate (DOP) on fatty acid composition of phosphatidylcholine (PC) in Tetrahymena pyriformis NT-1. When Tetrahymena cells were grown in DOP-containing proteose peptone medium, the cell growth was repressed. This repression was attended by decreases in the PC content of the cells and decreases in oleic (18:1), linoleic (18:2) and linolenic (18:3) acids of PC and an increase in palmitoleic acid (16:1). The ratio of 18:1/stearic acid (18:0) of PC in cells grown in DOP-containing medium was lower than that of control cells, while the ratio of 16:1/palmitic acid (16:0) was higher than that of control. On the other hand, no changes in the ratios of 18:2/18:1 and 18:3/18:2 were observed. The activity of microsomal stearoyl-CoA desaturase from cells grown with DOP (0.63 mumol/ml medium) decreased to 27% of that from control cells, while the microsomal palmitoyl-CoA desaturase activity increased to 210% of the control value. By the addition of dioleoyl glyceride to the DOP-containing medium, the effects of DOP on Tetrahymena cells were completely blocked. These results suggest that the changes in fatty acid composition of PC may be due to the alteration of the substrate specificity of microsomal delta 9-desaturase, and the decrease in stearoyl-CoA desaturase activity may be a cause for the cell growth repression.