Microassay of gamma-glutamyl transpeptidase in needle biopsies of human liver

A method is described for determination of liver gamma-GTP activity in homogenates of the small amount of human liver tissues (approx. 5--7 mg wet wt.) obtained by needle biopsy. The gamma-GTP activity in the liver of healthy subject was < 20 mU/mg protein. The microdetermination of gamma-GTP described here is worth in the diagnosis of hepatic injury, especially alcoholic hepatitis and drug-induced liver diseases.

Demonstration of a geometric isomer of bilirubin-IX alpha in the serum of a hyperbilirubinaemic newborn infant and the mechanism of jaundice phototherapy

Photobilirubin-IX alpha in the serum of a hyperbilirubinaemic newborn infant was demonstrated for the first time by reversed-phase high-pressure liquid chromatography. The concentrations increased significantly during phototherapy. Corresponding to these changes in the serum, biliary unconjugated bilirubin concentrations increased markedly but photobilirubin-IX alpha was not detected in the bile. Moreover, large amounts of 'unknown pigment' that are diazo-negative appeared in the bile during phototherapy.

High-pressure liquid chromatographic analysis of anaerobic photoproducts of bilirubin-IX alpha in vitro and its comparison with photoproducts in vivo

To carry out photochemical experiments under conditions similar to those prevailing for neonatal bilirubin metabolism in jaundice phototherapy, we have studied photoproducts produced by the action of light on a bilirubin--albumin solution and further clarified the relationship between the photoproducts obtained from experiments in vitro and in vivo. (1) An accurate and sensitive separation method by high-pressure liquid chromatography for photoproducts of bilirubin under anaerobic irradiation of visible light is described. (2) There were two main photoproducts obtained from experiments both in vivo and in vitro. (3) Exact correspondence of retention time on high-pressure liquid chromatography, diazo-reactivity, thermal reversion and absorption-spectrum maxima was observed between unknown pigment and photobilirubin-IX alpha from biological fluids, and the comparable peaks 2 and 3 from experiments in vitro. (4) The behaviour of photoproducts in various solutions in the absence of light and O2 is described. (5) A lower affinity of photoproducts, especially unknown pigment, for human serum albumin than with bilirubin-IX alpha for the albumin was demonstrated by the gel-filtration method.

Effects of surface potential and membrane potential on the midpoint potential of cytochrome c-555 bound to the chromatophore membrane of Chromatium vinosum

The values of midpoint potential (Em) of cytochrome c-555 bound to the chromatophore membranes of a photosynthetic bacterium Chromatium vinosum was determined under various pH and salt conditions. After a long incubation at high ionic concentrations in the presence of carbonylcyanide m-chlorophenylhydrazone, which was added to abolish electrical potential difference between the inner and outer bulk phases of chromatophore, the Em value was almost constant at pH values between 4.0 and 8.4. With the decrease of salt concentration, the pH dependence of the Em value became more marked. Under low ionic conditions, Em became more positive with the decrease of pH. Addition of salt made the value more positive or negative at pH values higher or lower than 4.5, respectively. Divalent cation salts were more effective than monovalent cation salts in producing the positive shift of Em at pH 7.8. The Em value became more positive when the electrical potential of the inner side of the chromatophore was made more positive by the diffusion potential induced by the K+ concentration gradient in the presence of valinomycin. These results were explained by a change of redox potential at the inner surface of the chromatophore membrane, at which the cytochrome is assumed to be situated, due to the electrical potential difference with respect to the outer solution induced by the surface potential or membrane potential change. The values for the surface potential and the net surface charge density of the inner surface of the chromatophore membrane were estimated using the Gouy-Chapman diffuse double layer theory.

Clinical analysis on steroids. XII. Occurrence of D-homoannulation during the hot acid hydrolysis of 5 beta-pregnane-3 alpha, 20 alpha-diol disulfate

Two D-homosteroids were isolated from the hydrolyzate of 5 beta-pregnane -3 alpha, 20 alpha-diol disulfate (II) when it was refluxed in 3N hydrochloric acid. The structures of these steroids have been elucidated as 17 alpha-methyl-D-homo-5 beta-androstane-3 alpha, 17a beta-diol (VI) and 17 alpha-methyl-17a beta-chloro-D-homo-5 beta-androstan-3 alpha-ol (VIII) by instrumental analyses. The former was identical with a synthetic specimen derived from 5 beta-pregnane-3 alpha, 20 beta-diol disulfate (IV) by uranediol rearrangement. The main hydrolyzates obtained were 17 alpha-ethyl-17 beta-methyl-18-nor-5 beta-androst-13-en-3 alpha-ol (V) and 5 beta-pregnane-3 alpha, 20 alpha-diol (III).

Salt-induced pH changes in spinach chloroplast suspension. Changes in surface potential and surface pH of thylakoid membranes

A pH decrease in chloroplast suspension in media of low salt concentration was observed when a salt was added at pH values higher than 4.4, while at lower pH values a pH increase was observed. The salt-induced pH changes depended on the valence and concentration of cations of added salts at neutral pH values (higher than 4.4) and on those of anions at acidic pH values (lower than 4.4). The order of effectiveness was trivalent greater than divalent greater than monovalent. The pH value change by salt addition was affected by the presence of ionic detergents depending on the sign of their charges. These characteristics agreed with those expected from the Gouy-Chapman theory on diffuse electrical double layers. The results were interpreted in terms of the changes in surface potential, surface pH and the ionization of surface groups which result in the release (or binding) of H+ to (or grom) the outer medium. The analysis of the data of KCl-induced pH change suggests that the change in the surface charge density of thylakoid membranes depends mainly on the ionization of carboxyl groups, which is determined by the surface pH. When the carboxyl groups are fully dissociated, the surface charge density reaches -1.0 +/- 0.1 . 10(-3) elementary charge/square A. Dependence of the estimated surface potential on the bulk pH was similar to that of electrophoretic mobility of thylakoid membrane vesicles.

Evidence of the directive effect of 17 beta-conjugate group on the enzymatic O-methylation of catechol estrogen

Incubations of 2-hydroxyestradiol (I), 2-hydroxyestradiol 17 beta-sulfate (II), and 2-hydroxyestradiol 17 beta-glucuronide (III) with purified rat liver catechol O-methyltransferase were carried out at pH 7.2 in the presence of Mg2+ and (3H-Me)-S-adenosyl-L-methionine. The radioactive methylated products, 2-methoxyestradiol (IV) and 2-hydroxyestradiol-3-methyl ether (V), from each substrate were quantificanted by reverse isotope dilution method after their complete separation and acetylation. In the experiments of conjugated substrates, II and III, the analyses of the methylated products were done after their hydrolysis of 17 beta-conjugate groups with acid or beta-glucuronidase. The product ratios (2-methoxy/3-methoxy) of substrates I, II, and III, were 1:1, 4:1, and 45:1, respectively. These results are suggesting that 17 beta-conjugate groups of 2-hydroxyestradiol has directive effect on enzymatic O-methylation of estrogen catechols. Further, it is estimated that following process may be present in the estradiol metabolism in rat and/or humans: estradiol leads to estradiol 17 beta-conjugates leads to 2-hydroxyestradiol 17 beta-conjugates leads to 2-methoxyestradiol 17 beta-conjugates.

Effects of surface potential on the equilibrium and kinetics of redox reactions of membrane components with external reagents in chromatophores from Rhodopseudomonas sphaeroides

The characteristics of the salt and pH dependences of the redox levels of cytochrome c2 and reaction center bacteriochlorophyll were studied in chromatophores from Rhodopseudomonas sphaeroides. They could be explained in terms of the difference of redox potential in the membrane from that in the bulk aqueous phase due to the electrostatic potential difference arising from charges fixed on the membrane surface. The midpoint potentials (Em) became lower when the surface potential (the electrostatic potential at the surface with reference to the bulk aqueous phase) had large negative values at lower salt concentrations at neutral pH, as predicted by the Gouy-Chapman theory. The rate of oxidation of cytochrome c2 in chromatophores by ferricyanide also depended on salt and pH levels. The rate was low at low salt concentrations, probably because of the lower surface concentration of ferricyanide compared with the bulk concentration, due to the surface potential.

Effect of neonatal hydrocortisone treatment on brain monoamines in developing rats

In our previous study, neonatal treatment with hydrocortisone was shown to produce a marked retardation of pituitary-adrenocortical development in infant rats. The present investigation was an attempt to determine whether or not the retarded activity is caused by functional changes in brain monoamine systems. In rats treated with hydrocortisone (0.5 mg/rat, s.c.) on the 2nd day of life, the development of whole brain was suppressed significantly. However, norepinephrine, dopamine and serotonin contents in the brain were higher in these rats than controls. These changes of monoamine contents were apparent in the hypothalamus, diencephalon and pons-medulla oblongata. Our data suggest that monoaminergic nervous systems are potentiated with hydrocortisone in these brain regions, although the results do not necessarily explain the retarded hypothalamo-pituitary function.

Composite ganglioneuroblastoma--a case report and short term culture of tumor cells

A 1-year-old male infant showed cerebellar signs and symptoms, and excess urinary excretion of vanillylmandelic acid (VMA). Each of them disappeared spontaneously but a large abdominal tumor occurred at 3 years of age. Surgical specimen of the tumor was diagnosed as neuroblastoma and the patient died at 4 years of age. Autopsy revealed the huge tumor originated from the right adrenal, and occupying the retroperitoneum, pelvic cavity and posterior mediastinum. Histology of the primary lesion was chiefly that of ganglioneuroma, while all of the metastatic ones neuroblastoma. Transitional histology from neuroblastoma to ganglioneuroma was also observed in the primary lesion. The diagnosis was designated as composite ganglioneuroblastoma. The surgical material of the metastatic neuroblastoma was cultured for 2 months in vitro and the tumor cell clumps extended spontaneously abundant long neurites. This phenomenon suggests the high maturation ability of the neuroblastoma cells.

Conditioned circadian rhythm of plasma corticosterone in the rat induced by food restriction

Earlier observations that food restriction for a short period of time in the morning produced an altered circadian rhythm of plasma corticosterone having the peak just before feeding time, and that the elevated plasma corticosterone levels declined promptly immediately after food presentation were confirmed. After a 14-day restricted feeding schedule, where food was given from 11:00 to 13:00, if food was not given, elevated levels of plasma corticosterone were sustained for at least 1 hr and then declined gradually. On the other hand, if food was given 2 hr earlier than the scheduled time, the peak at 11:00 disappeared. The conditioned peak of plasma corticosterone was maintained for at least 3 days after the restricted feeding schedule if hypertonic saline, but not tap water, was given without food in male rats and ovariectomized female ones. When female rats were treated with lysine vasopressin for 5 days 10 min before the food presentation, highly elevated levels of plasma corticosterone were found at the time of food presentation. However, administration of cortisol 2 hr before the feeding time blocked the effect of vasopressin. The results suggest that vasopressin is involved in the acquisition and consolidation of the conditioned circadian rhythm of plasma corticosterone induced by restricted feeding.

An accurate and sensitive analysis by high-pressure liquid chromatography of conjugated and unconjugated bilirubin IX-alpha in various biological fluids

An accurate and sensitive method was developed for the complete separation of the native tetrapyrroles, such as bilirubin and its mono- and di-conjugates of glucuronic acid, glucose and xylose, by ion-pair reversed-phase high-pressure liquid chromatography. The application of this method was demonstrated by the analysis of bile pigments in human bile and urine, and the method also makes it possible to estimate very low UDP-glucuronyltransferase activity, such as is found in the human foetal and neonatal liver.

The rate of phase shift of plasma corticosterone circadian rhythm during early developmental stages in neonatally blinded rats

The phase shift of circadian periodicity of pituitary-adrenocortical activity was studied in neonatally blinded infant rats. The phase shift of the rhythm was surprisingly rapid during the early stage of prepubertal period, while changes in the rhythm pattern were rather small after puberty, as indicated by a slight shift of the acrophase. Low amplitude was observed in the group data of blinded rats after puberty.

Effect of a cholecystokinin preparation on brain monoamines in the rat

In order to elucidate the central action mechanism of cholecystokinin (CCK), effects of this peptide on norepinephrine, dopamine and serotonin contents in the brain were observed in saline control, alpha-methyl-p-tyrosine-, L-DOPA- and pargyline-pretreated rats. Intraperitoneal injection of CCK in a dose of 40 U/kg did not produce any significant changes in the monoamine contents. However, since a tendency to increase in norepinephrine turnover rate after CCK injection was noticed, the possibility that brain monoamines are involved in the central action of CCK could not be excluded.

Postnatal development of uridine diphosphate glucuronyltransferase activity towards bilirubin and 2-aminophenol in human liver

UDP-glucuronyltransferase activities towards 2-aminophenol and bilirubin were studied in a total of 70 human subjects, including premature and full-term newborn babies, infants, children and adults. These two activities have been reported in rat to develop latefoetally and neonatally respectively, but in man they both develop neonatally. There is a linear relationship between the logarithm of each liver transferase activity and the logarithm of the number of days after birth during the first 3 months of life, after which each activity remains constant.

Surface potential and reaction of membrane-bound electron transfer components. I. Reaction of P-700 in sonicated chloroplasts with redox reagents

Salt- or pH-induced change of the rate of reduction of the photoxidized membrane bound electron transfer components, P-700, by ionic and nonionic reductants added in the outer medium was studied in sonicated chloroplasts. The rate with the negatively charged reductants increased with the increase of salt concentration at a neutral pH or with the decrease of medium pH. Salts of divalent cations were much more effective than those of monovalent cations. A trivalent cation was even more effective. The rate with a nonionic reductant was little affected by salts. The change of the reduction rate was analysed using the Guoy-Chapman theory, which explains the change of reduction rate by the changes of activities of ionic reductants at the charged membrane surface where the reaction takes place. This analysis gave more useful parameters and explained more satisfactorily the case with high-valence cation salts than the Brönsted type analysis. The values for the surface charge density and the surface potential of the membrane surface in the vicinity of P-700 estimated from the analysis were lower than those estimated for the surface in the vicinity of Photosystem II primary acceptor, suggesting the heterogeneity of the thylakoid surface. The salt-induced surface potential change was shown to affect the activation energy of the reaction between P-700 and the ionic reagent.

Surface potential and reaction of the membrane-bound electron transfer components. II. Integrity of the chloroplast membrane and reaction of P-700

Electrostatic characteristics of the membrane in the vicinity of P-700 were estimated by analyzing the salt and detergent effects on its reaction rate with ionic reagents using the Gouy-Chapman diffuse double layer theory in various preparations of chloroplasts. Upon disruption of thylakoid membranes by sonic treatment or by treatment with digitonin, the reaction rate markedly increased, while the estimated surface charge density became smaller. It was concluded that the membrane surface which determines the reaction rate between P-700 and the ionic reagents changed as the disruption of thylakoid structure. The outer thylakoid surface had more negative charges than the inner one. Changes in the electrical potential profile across the thylakoid membrane during the illumination were also discussed from these results.

Circannual variation of mortality rate following a single injection of hydrocortisone in newborn rats

Under constant experimental conditions of room temperature and illumination, a highly significant seasonal difference was observed in the mortality rate of rats which received hydrocortisone on the first day of life. The rate was high in winter and low in summer. Inborn circannual variation of the susceptibility to exogenous corticosteroid was shown to exist in newborn rats.

Suppressive effect of pentagastrin on pituitary-adrenocortical secretion

The effect of pentagastrin on the pituitary-adrenocortical secretion was examined in male rats. In the morning the intraperitoneal injection of this peptide produced a slight, but significant, decrease in the plasma corticosterone levels, but it had no effect on the evening rise due to circadian periodicity and the stress-induced elevation of the plasma corticosterone level. Following intracerebroventricular administration of pentagastrin, plasma corticosterone tended to decrease and in in vitro incubation of rat pituitary tissue the addition of pentagastrin elicited a suppressive effect on the ACTH release from the tissue into the medium. It was suggested that gastrin-like peptide might control the secretion of ACTH.

Isolation and characterization of stable hybrid mRNA molecules transcribed from ribosomal protein promoters in E. coli

The promoters from the str and spc operons of ribosomal proteins from E. coli were inserted into the Hind II cleavage site of mini-Col E1 (pVH51) plasmid. For both promoters, strains with the hybrid plasmid accumulated a small RNA species not present in strains carrying the vector. These RNAs were analyzed by RNA sequencing techniques and compared to DNA sequences. In both cases, synthesis of the new RNA species is initiated by the cloned r protein promoter at the site predicted by previous in vitro experiments. The RNAs extend across the Hind II site used for cloning and terminate specifically in the vector sequences. The termination site was localized to six consecutive thymine nucleotides preceded by a sequence with dyad symmetry. We found that the RNA from the str promoter was 205 (+/- 3) nucleotides long and that from the spc promoter was 177 (+/- 3) nucleotides long. These "hybrid mRNAs" are much more stable than ordinary mRNA. The str hybrid mRNA has a half-life of about 8 min, and the spc hybrid mRNA has a half-life of about 18 min at 37 degrees C. These hybrid mRNAs provide an in vivo system with which to examine directly the discrete transcription products from ribosomal protein promoters, and to study promoter function and mRNA metabolism in vivo.

A high potential acceptor for photosystem II

The effects of ferricyanide on Photosystem II reactions have been investigated by measurements of microsecond and millisecond prompt fluorescence and microsecond-delayed fluorescence in dark-adapted chloroplasts: (1) Titrations using ferri-ferrocyanide mixtures on: (a) the fast phase of the increase in fluorescence yield observed during a xenon flash, and (b) the normalised area above the millisecond fluorescence induction curve for chloroplasts inhibited by DCMU, showed a pH dependent mid point potential of 400 mV at pH 7.0 which varied by approx. -60 mV/pH unit between pH 6 and 8.5. (2) A saturating laser flash induced a fluorescence increase (as monitored by a weak measuring beam) of only 50% of that reached following a second flash in chloroplasts preincubated with ferricyanide and inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) prior to illumination. In the absence of ferricyanide, the fluorescence level reached after a single flash was initially close to that measured after a second flash (although the level subsequently declined). (3) The initial amplitude of the microsecond-delayed fluorescence excited by a single laser flash was diminished in chloroplasts dark-adapted with ferricyanide. In the presence of DCMU and ferricyanide, the amplitude was also diminished for the first flash of a series, but subsequently enhanced above the level obtained in chloroplasts in the presence of DCMU alone. (4) The above effects were not seen if DCMU was added to the chloroplasts before ferricyanide, or if the period of incubation with ferricyanide was much less than 4 min. (5) These results suggested the presence of a second acceptor Q2, with Em7 = 400 mV and n = 1, before the DCMU block in Photosystem II. There is 0.35--1 equivalent of the acceptor per reaction centre, and its reduction occurs within less than 5 mus. The role of the acceptor in double turnovers of the photochemistry during a single flash and its likely operating redox potential are discussed.

Effects of pH on reactions on the donor side of photosystem II

The effects of pH on the increase of fluorescence yield measured in the microsecond range, and on the microsecond delayed fluorescence have been studied in dark adapted chloroplasts as a function of flash number. (1) At pH 7, the amplitude of the fast-phase of the microsecond fluorescence yield rise oscillated as a function of flash number with period 4 and with maxima on flashes 1 and 5, and minima on flashes 3 and 7. The damped oscillations were apparent over the range between 6 and 8, although the absolute amplitude of the fast phase was diminished at the lower end of the range. At pH 4, there was no fast phase in the rise and, at pH 9, an enhanced fast-phase occurred only for the first flash. (2) The decay of microsecond delayed fluorescence was described by the sum of exponentials with half-times of 10--15 mus and 40--50 mus. Over the pH range 6- less than 8, the extrapolated initial amplitude and the proportion of the change due to the faster component showed oscillations which were opposite in phase to those observed for the prompt fluorescence yield rise; the slower component showed weaker oscillations of the same phase. At pH 4, there were no oscillations and the slow phase predominated. At pH 9, the delayed fluorescence intensity was diminished on the first flash, and high on subsequent flashes. (3) The results are interpreted in terms of a model in which protons are released during all transitions of the S-states with the exception of S1 leads to S2, and in which ther are two sites of inhibition on the donor side of the photo-system at extreme pH values. At pH 4, electron donation to P+ occurs with a half-time approx. 135 mus, either by a back reaction from Q-, or from D; electron transport is interrupted between Z1 and P. At pH 9, electron transport is inhibited between Z1 and Z2; rapid re-reduction of P+ by Z1 occurs after 1 flash, and on subsequent flashes electrons from D, an alternative donor reduce P+. The location of the positive charge on states S2 and S3 is discussed.

Effect of surface potential on the intramembrane electrical field measured with carotenoid spectral shift in chromatophores from Rhodopseudomonas sphaeroides

Changes in the surface potential, the electrical potential difference between the membrane surface and the bulk aqueous phase were measured with the carotenoid spectral shift which indicates the change of electrical field in the membrane. Chromatophores were prepared from a non-sulfur purple bacterium, Rhodopseudomonas sphaeroides, in a low-salt buffer. Surface potential was changed by addition of salt or by pH jump as predicted by the Gouy-Chapman diffuse double layer theory. When a salf was added at neutral pH, the shift of carotenoid spectrum to shorter wavelength, corresponding to an increase in electrical potential at the outside surface, was observed. The salts of divalent cations (MgSO4, MgCl-2, CaCl2) were effective at concentrations lower than those of monovalent cation salts (NACl, KCl, Na2SO4) by a factor of about 50. Among the salts of monoor divalent cation used, little ionic species-dependent difference was observed in the low-concentration range except that due to the valence of cations. The pH dependence of the salt-induced carotenoid change was explained in terms of the change in surface charge density, which was about 0 at pH 5--5.5 and had negative values at higher pH values. The dependence of the pH jump-induced absorbance change on the salt concentration was also consistent with the change in the charge density. The surface potential change by the salt addition, which was calibrated by H+ diffusion potential, was about 90 mV at the maximum. From the difference between the effective concentrations with salts of mono- and divalent cations at pH 7.8, the surface charge density of (-1.9 +/- 0.5) . 10(-3) elementary charge per A2, and the surface potential of about -100 mV in the presence of about 0.1 mM divalent cation of 5 mM monovalent cation were calculated.

Study on trace impurity elements in highly purified iron and aluminum by neutron activation analysis

Activation analysis was carried out on the purified iron and aluminum to study the behavior of trace impurities on purification process, and to estimate the purity of the purified samples. Thermal neutrons with high Cd ratio through D2O column or graphite column were used for the activation of samples to reduce the interference effects by fast neutrons, the reactions, (n, p) or (n, a), from matrix elements. On the zone refined aluminum, the segregation of impurity elements was cleary observed. In the case of iron, decrease of impurity content was confirmed on superposing the various purification processes.

Five patients with nonalcoholic diabetic cirrhosis

Five nonalcoholic diabetic women were clinically and histologically verified as having micronodular cirrhosis. In this series all the patients were over 50 years of age, and showed obesity, hyperglycemia, enlarged liver and mild abnormalities of liver function tests. The histological findings differed from hepatitic cirrhosis. In two patients serial biopsies confirmed development of cirrhosis from centrilobular necrosis.

[General pharmacological studies on pepleomycin sulfate (NK 631) (author's transl)]

Pharmacological actions of pepleomycin sulfate (NK 631) which is a new antitumor agent derived from bleomycin were studied and the following results were obtained. NK 631 had no significant influences on the central, motor and sensory nervous systems at relatively higher doses (5 approximately 10 mg/kg, i.v., i.p., s.c.). NK 631 (5 approximately 10 mg/kg, i.v.) caused a slight decrease in blood pressure in anesthetized rats and slight increases in blood pressure, heart rate and peripheral blood flow in anesthetized dogs. NK 631 (1 approximately 3 mg) given close-arterially caused a slight increase in the developing tension in the isolated blood-perfused papillary muscle. NK 631 slightly contracted the isolated guinea pig ileum and rat uterus but did not affect the contraction of isolated guinea pig trachea. NK 631 caused significant increases in urine output and Cl excretion in saline loaded rats at 20 mg/kg, i.p. By the local injection of NK 631, a slight edema of rat paw and an increase in rabbit cutaneous permeability were observed. The intraperitoneal injection of NK 631 caused a significant increase in leakage of dye injected intravenously into the peritoneal cavity of mice. NK 631 did not affect hemolysis and prothrombin time at 10(-4) g/ml. In pharmacological actions, significant differences between NK 631 and pepleomycin were not observed.

Membrane surface potential and the reactivity of the system II primary electron acceptor to charged electron carriers in the medium

A hypothesis is proposed to explain the changes in the apparent rate constant for the reaction between the primary electron acceptor of System II situated in the thylakoid membrane and the artificial electron acceptors added in the medium. Dark oxidation rate of the primary acceptor by artificial electron acceptors was monitored by measuring the induction of chlorophyll fluorescence in the presence of an electron transport inhibitor, 3-(3',4'-dichlorophenyl)-1,1-dimethylurea, in spinach chloroplasts. The apparent rate constant for the oxidation changed widely when the medium pH or salt concentrations were varied, or ionic detergents were added. The change was quantitatively ascribed (1) to the change in the local concentration of electron acceptors at the thylakoid surface due to the electrical potential difference between the surface and the bulk aqueous phase (Gouy-Chapman diffuse double layer theory) and (2) to the situation whereby the apparent rate constant is determined with respect to concentration in the bulk phase. Values for the surface potential in the vicinity of System II were estimated from the change in the apparent rate constant under various conditions. The results closely agreed with those obtained previously from the rate constant of the dark step of the System II-dependent Hill reaction with ferricyanide (Itoh, S. (1978) Plant Cell Physiol. 19, 149--166). Application of the hypothesis to various reactions between the added ionic reagents and the endogenous components in the membrane or between the endogenous components situated in different parts of the membrane is discussed.

[Postnatal development of adrenocortical circadian rhythm in neonatally cortisol- and estriol-treated rats (author's transl)]

The effect of a single neonatal administration of cortisol and estriol on the development of the adrenocortical circadian rhythm was investigated in immature rats. In normal control rats of both sexes, the plasma corticosterone rhythm was discernible on day 21. In male rats the adult pattern was observed on day 28, but in females as the plasma corticosterone level elevated progressively during puberty, the rhythm increased in amplitude and the adult pattern was established at 8 weeks of age. In neonatally cortisol-treated rats, the plasma corticosterone rhythm appeared at 4 weeks of age, but the plasma level was significantly lower than that of the controls until 6 weeks and attained a level similar to the controls at 8 weeks. Neonatally estriol-treated rats exhibited the rhythm as early as 2 weeks of age, but this was temporary. It disappeared at 3 weeks and reappeared a 4 weeks. Although 5-week-old males showed normal rhythm as seen in the controls, in females the plasma corticosterone level remained low for weeks and approached the control level at 8 weeks of age. The development of circadian periodicity of adrenal corticosterone content almost paralleled that of plasma corticosterone not only in the controls but also in steroid-treated groups, but the rhythm was occasionally equivocal. In neonatally estriol-treated rats, stress response of plasma and adrenal corticosterone to ether was similar to that of the controls, but the response to exposure to a strange environment was significantly small.

On the role of the pineal in thermoregulation in the pigeon

Diurnal rhythm in body temperature of pigeons subjected to different experimental conditions (pinealectomized, sham-operated, melatonin-implanted, cold-exposed) was studied under a 12 h light and 12 h dark regimen. The body temperature of pigeons during photophase was higher than that during scotophase in the normal as well as every treatment group studied. Pinealectomized pigeons showed higher body temperature in the photophase as well as scotophase, than that of the normal and sham-operated birds when examined 2 or 3 weeks following the post-surgical acclimatization to 25 or 3 degrees C. However, subcutaneous implantation of melatonin pellets into pinealectomized pigeons nullified or even reversed the hyperthermic effect of pinealectomy. Exposure of pigeons to--18 degrees C for 280 min during photophase as well as scotophase, produced a marked drop in body temperature in pinealectomized, sham-operated and normal pigeons. The pinealectomized pigeons exhibited a higher body temperature than that of the sham-operated and normal ones when exposed to--18 degrees C during the photophase, but not during the scotophase. It was concluded that while the pineal is not necessary for maintaining the daily thermal rhythm in the avian body, it has a thermoregulatory role, in that it prevents rise in body temperature in warm (25 degrees C) acclimatized and chronic cold (3 degrees C) exposed birds. In acute short-term cold (--18 degrees C) exposure however, the temperature regulatory role of the pineal was not effective during the scotophase.

Nonalcoholic fatty liver with alcoholic hyalin after long-term glucocorticoid therapy

Alcoholic hyalin was found in liver of a nonalcoholic patient with fatty liver after long-term glucocorticoid therapy for systemic lupus erythematosus. Hepatocytes including hyalin bodies showed fatty change or vesiculated degeneration. Occasionally, basophilic substance which was recognized in the hepatocytes with or without hyalin was noticed showing the feature quite similar to delicate alcoholic hyalin.

A new enzymatic method for determination of serum choline-containing phospholipids

A new enzymatic method is presented for the determination of serum choline-containing phospholipids with a combined enzymatic method using phospholipase D (from Streptomyces species), choline oxidase (from Arthrobacter species) and peroxidase. The method is reproducible, and the results correlate well with those obtained by the conventional digestion method (Hoeflmayr, J. and Fried, R. (1966) Med. Ernaehr. 7, 9-10). The method affords better specificity, requires a smaller quantity of the sample and shorter time than those previously reported, and has excellent precision.

[Changes in adrenal gland and thymus induced by sex steroid administration in newborn rats (author's transl)]

Testosterone, dehydroepiandrosterone (DHEA), progesterone, estradiol-17beta, estrone, estriol, 2-hydroxyestradiol-17beta, 2-hydroxyestriol, deoxyestrone and diethylstilbestrol were injected s.c. in a dose of 0.5 mg each into newborn rats on the first day of life, and changes in the adrenal gland, thymus and spleen were examined 3 days later. Increase in the body weight during the 3 days was less in rats treated with DHEA, 2-hydroxyestriol and deoxyestrone, as compared with that in controls. Development of the thymus was significantly impaired in rats injected with various kinds of sex steroids, except progesterone and diethylstilbestrol. Reduction of the spleen weight by sex steroid treatment was not marked. The weight of adrenal gland decreased in rats injected with DHEA and progesterone, while the weight increased in those given estrone and diethylstilbestrol. Estrogens, particularly estriol, induced a marked increase in adrenal corticosterone content, while 2-hydroxyestriol caused only slight elevation and 2-hydroxyestradiol and deoxyestrone had no influence on the content. Suppressive effect of cortisol on the adrenal gland of newborn rats was slightly, but significantly, lessened by estriol treatment. From the results, physiological role of estriol and DHEA in adrenal secretion was discussed.

[Postnatal development of the adrenal gland in the rat (author's transl)]

Postnatal development of adrenocortical function of rats was studied. During the first week after birth the increase in adrenal weight was very slight. Consequently, the relative weight of the gland per body weight decreased progressively during the postnatal 14 days. However, adrenal corticosterone concentration showed a gradual elevation over this period of postnatal days. Adrenal corticosterone response to ether stress did not appear in male rats at 12 days of age, but a distinct response was observed in female ones at the same age. A sex difference in the duration of the stress-nonresponsive period is likely to exist in newborn rats. In accord with the stress-nonresponsive period, the thymus-lymphatic system showed a marked development. The pattern of circadian periodicity of plasma corticosterone levels in 21-day-old rats was somewhat different from that in adult rats. Peak value of the corticosterone rhythm was attained at 0300 in the infant rats. A sex difference was again noticed in the evening rise of plasma corticosterone level in these infant rats: the rise was steeper in females than in males. A significant circadian periodicity was observed in female rats at 14 days of age, but the periodicity was equivocal in male ones at the same age.