Monoacylcadaverines in the blood of schizophrenic patients

Concentrations of cadaverine, monoacetylcadaverine and monopropionylcadaverine in the blood of schizophrenic and nonschizophrenic subjects were measured. Two groups, one from the U.S.A. the other from Japan, were tested. Monoacetylcadaverine and monopropionylcadaverine were found elevated in the blood of some schizophrenic patients in comparison with those in controls in each group. Their increase could be caused by a reduced monoamine oxidase activity or by an increased acylation in schizophrenic patients.     

Duality of alpha-subunit of canine kidney sodium- and potassium-activated adenosinetriphophatase in electrophoresis

Sodium- and potassium-activated adenosinetriphosphatase (Na+, K+-ATPase) purified from dog kidney outer medulla was examined by polyacrylamide gel electrophoresis and by photoaffinity labeling with N-(ouabain)-N'-(2-nitro-4-azidophenyl)-ethylenediamine (NAP-ouabain). The large subunit band (alpha-band) split into two bands on the gel after the enzyme was heat-treated in the presence of 1% sodium dodecylsulfate (SDS). Of the two bands (alpha I and alpha II), alpha I had the same electrophoretic mobility as the original band, while alpha II moved slightly faster. Total conversion into alpha II was not observed, about half of the original remaining as alpha I. Below 60 degree C, heat treatment did not produce alpha II. Phenylmethylsulfonyl fluoride did not prevent the appearance of alpha II. Both alpha I and alpha II were labeled with [3H]NAP-ouabain. Nonspecific incorporation of [3H]NAP-ouabain also occurred irrespective of illumination, but it was removed either by diffusion during staining and destaining of the gel or by treatment of the enzyme with trichloroacetic acid. It is tentatively concluded that the splitting of the band reflects some intrinsic differences in situ of the alpha-subunit of dog kidney membrane Na+,K+-ATPase.     

Epinephrine-stimulated phosphorylation of pyruvate kinase in hepatocytes

Incubation of rat liver parenchymal cells with 10^?5m epinephrine or norepinephrine resulted in a rapid incorporation of ³²P into pyruvate kinase. Inclusion of α-adrenergic blocking agents (phenoxybenzamine or phentolamine) in the hepatocyte incubation medium prior to addition of epinephrine suppressed the subsequent phosphorylation of pyruvate kinase. On the other hand, inclusion of the β-adrenergic antagonist, propranolol, in the hepatocyte incubation medium prior to addition of epinephrine did not suppress the epinephrine-elicited phosphorylation of pyruvate kinase. Exogenous addition of either cyclic AMP or cyclic GMP to the hepatocyte incubation medium also resulted in increased phosphorylation of pyruvate kinase. To investigate whether the same amino acid residue(s) of liver pyruvate kinase was being phosphorylated in each instance, ³²P-labeled pyruvate kinase was isolated from hepatocytes after incubation in the presence or absence of either glucagon or epinephrine. In addition, purified liver pyruvate kinase was phosphorylated in vitro with a rat liver cyclic AMP-dependent protein kinase. Each ³²P-labeled pyruvate kinase was then subjected to tryptic digestion, two-dimensional thin-layer peptide mapping, and autoradiography. Each ³²P-labeled pyruvate kinase sample yielded 44 to 48 tryptic peptides upon staining with ninhydrin and 4 peptides that contain ³²P as detected by autoradiography. Furthermore, the same 4 peptides of pyruvate kinase were radiolabeled in each instance. Thus phosphorylation of pyruvate kinase in vitro with [γ-³²P]ATP or upon addition of either glucagon or epinephrine to hepatocytes incubated with ³²P_i resulted in phosphorylation of the same amino acid residues.     

Habituation in suspension-cultured soybean cells to thiamine and its precursors

When thiamine concentration in subculture medium was rapidlylowered to nil, soybean cells in suspension became necroticand stopped growing entirely. When it was gradually lowered,cell growth was vigorous until the concentration was reducedto 7.8?10^–3 mg/liter. The cells at this level of thiamineceased growing for a time, but prolonged culture in the samemedium resulted in the appearance of fresh white cells whichcould be easily distinguished from the old brown, necrotic cellsin the aggregates. These new cell lines could be subculturedwith further reduction in the thiamine supply, growing as largeraggregates of about 4 mm in diameter. New cell lines were similarly obtained by prolonged culturesin media containing a thiamine precursor; three lines appearedto be habituated to the pyrimidine moiety and one to the thiazolemoiety. The latter cell line could be subcultured without thiamineand its precursors for at least eight passages. These habituatedcells were characterized by the increase of the dry to freshweight ratio and by their growth in large aggregates. ¹Present address: Section of Phytochemical Research, Eisai Co.,Ltd., Kawashima, Gifu 483, Japan. (Received December 15, 1978; )     

A self-organizing neural network model for the development of complex cells

On the basis of recent neurophysiological findings on the mammalian visual cortex, a selforganizing neural network model is proposed for the understanding of the development of complex cells. The model is composed of two kinds of connections from LGN cells to a complex cell. One is direct excitatory connections and the other is indirect inhibitory connections via simple cells. Inhibitory synapses between simple cells and complex cells are assumed to be modifiable. The model was simulated on a computer to confirm its behavior.     

Cycloamylose-accelerated cleavage of acylimidazoles

Hydrolyses of N-trans-cinnamoylimidazole (1) and N-acetylimidazole (2) were accelerated by cyclohexaamylose (α-CA) and cycloheptaamylose (β-CA) at 25°C. The cleavage of the amide bond in 1 at pH 9.0 was accelerated by α-CA and β-CA by 28- and 38-fold, respectively, whereas the cleavage of the amide bond in 2 at pH 7.0 was accelerated by α-CA and β-CA by 50- and 28-fold, respectively. The β-CA-accelerated hydrolysis of 1 proceeded via binding, acylation of β-CA, and deacylation of β-CA trans-cinnamate, which is consistent with the pathway used by serine proteases. The deuterium oxide solvent isotope effects for acylation and deacylation steps indicate nucleophilic attack in acylation and general basic attack in deacylation. The present finding of the acceleration by cycloamyloses in the cleavages of amide bonds in 1 and 2 indicates that cycloamyloses are an excellent model for hydrolytic enzymes.     

Radioimmunoassay for β-endorphin: Presence of immunoreactive “big-big” β-endorphin (“big” β-lipotropin) in human and rat pituitaries

A sensitive and specific radioimmunoassay for β-endorphin has been developed with an antiserum obtained in a rabbit immunized with β-endorphin contained in crude porcineACTH preparations. The minimal detectable quantity was 5 pg. The antiserum used reacted slightly with ovine β-lipotropin (5.5 %), but showed negligible cross-reactivity with other fragments of β-lipotropin, α-MSH and ACTH. Using this radioimmunoassay we have observed the presence of “big-big” β-endorphin (“big” β-lipotropin) with apparent molecular weights of 37,000 and 31,000 in human and rat pituitaries respectively, in addition to β-lipotropin and β-endorphin, by Sephadex gel-chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis.     

Abscisic acid from Pinus densiflora pollen

(+)-Abscisic acid was isolated as the methyl ester from Pinus densiflora pollen and identified spectroscopically.