Lysophosphatidic acid as a stimulator of Na(+)-dependent Ca2+ efflux from adrenal chromaffin cells

The effect of lysophosphatidic acid (LPA) on Ca2+ efflux from cultured bovine adrenal chromaffin cells was examined. LPA stimulated the efflux of 45Ca2+ from the cells in a concentration dependent manner (10(-7)-10(-5)M). Other lysophospholipids (lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylinositol and lysophosphatidylserine), phosphatidic acid, monoolein and oleic acid had not significant effect on 45Ca2+ efflux from the cells. The LPA-stimulated 45Ca2+ efflux was dependent on the extracellular Na+ concentration and was inhibited by amiloride, inhibitor of Na+/Ca2+ exchange. LPA increased 22Na+ uptake into the cells and this effect was also sensitive to amiloride. These results indicate that LPA stimulates extracellular Na(+)-dependent 45Ca2+ efflux from cultured bovine adrenal chromaffin cells, probably through its stimulatory effect on membrane Na+/Ca2+ exchange.

Effects of branched-chain amino acid infusion on protein metabolism in rats with acute hepatic failure

Branched-chain amino acids (BCAA) are known to improve hepatic encephalopathy as well as protein malnutrition in cirrhosis. However, such effects in acute hepatic failure (AHF) remain to be elucidated. The current study was conducted to investigate whether BCAA improves protein metabolism in AHF. AHF was induced in male Donryu rats weighing approximately 230 g by giving 60 mg/kg lipopolysaccaride intravenously and 800 mg/kg D-galactosamine hydrochloride intraperitoneally. From 18 hours after injection, AHF rats and control rats were given one of the following five solutions intravenously for 6 hours: 1) saline, 2) 10% glucose, 3) standard 10% amino acid formula with total nitrogen content of 12.2 g/L and BCAA/aromatic amino acid molar ratio of 37.05, 4) BCAA-enriched solution with nitrogen content of 21.9 g/L and the ratio of 148.2, or 5) an active placebo against BCAA-enriched solution with nitrogen content of 21.9 g/L and the ratio of 37.05. In parallel, each group was given a continuous infusion of 14C-leucine. After the plasma radioactivity of 14C-leucine and the expired 14CO2 level reached a plateau, protein turnover was analyzed according to the kinetic model proposed previously by Waterlow. When compared with the control, rates of total protein turnover (total flux), oxidation, and breakdown all increased significantly in AHF. Infusion of standard 10% amino acid formula, BCAA-enriched solution or the placebo in AHF increased total flux and oxidation significantly as compared with the effect of saline or 10% glucose. Although saline, 10% glucose, standard 10% amino acid formula, and the placebo had no effect on synthesis rate, it was increased significantly with BCAA-enriched solution.(ABSTRACT TRUNCATED AT 250 WORDS)

Pituitary adenylate cyclase-activating polypeptide stimulates the synthesis of dopamine in cultured bovine adrenal chromaffin cells

The effect of pituitary adenylate cyclase-activating polypeptide1-38 (PACAP1-38) on the synthesis of dopamine in cultured bovine adrenal chromaffin cells was examined. PACAP1-38 stimulated [14C]dopamine synthesis from [14C]tyrosine, in a concentration-dependent manner, causing maximal stimulation at 10(-7)M. This stimulatory action of PACAP1-38 was not significantly inhibited by staurosporine (an inhibitor of protein kinase C) or in the cells in which protein kinase C was down-regulated by prolonged exposure to TPA (an activator of protein kinase C), whereas it was partially attenuated in Ca(2+)-free medium. PACAP1-38 increased the formation of [3H] inositol phosphates, [Ca2+]i, 45Ca2+ uptake and cAMP level. The peptide also stimulated the phosphorylation of tyrosine hydroxylase, the enzyme catalyzing the rate-limiting step in dopamine synthesis. Dopamine synthesis and tyrosine hydroxylase phosphorylation stimulated by the maximal effective concentration of dibutyryl cAMP or high K+, which activates Ca2+ uptake, were further enhanced by PACAP1-38. These results indicated that PACAP1-38 may stimulate the activities of cAMP- and calcium-dependent protein kinases in cultured bovine adrenal chromaffin cells, resulting in increase in the synthesis of dopamine probably by stimulation of phosphorylation of tyrosine hydroxylase.

[The changes in nuclear DNA content in acquisition of a high capacity for metastasis of human cell lines]

Quantification of nuclear DNA content in cancer is considered a prognostic factor, and several investigators have demonstrated that aneuploid tumors are more aggressive than diploid tumors. In this report, we investigated the relationship between metastatic capacity and nuclear DNA content using gastric and colon cancer cell lines. We established a highly peritoneal metastatic cell line (2M-D3) from a gastric cancer cell line (2M) and a highly liver metastatic cell line (LM-H3) from colon cancer cell line (LM) in our laboratory. Both the highly metastatic cell lines have more capacity for growth and metastasis, but lower nuclear DNA content and chromosome numbers than these parental cell lines. The results indicated that metastatic capacity was inversely proportional to nuclear DNA content. We cannot provide a satisfactory explanation for this inverse correlation between metastatic capacity and nuclear DNA content, but it is supposed that each cancer cell may have suitable and stable nuclear DNA content in metastasis.

Role of SPan-1 antigen in adhesion of human colon cancer cells to vascular endothelium

Recently E-selectin (ELAM-1, endothelial leukocyte adhesion molecule-1) was shown to recognize not only sialyl Lewis X but also sialyl Lewis A, and these carbohydrate antigens may be involved in the process of the adhesion between cancer cells and endothelial cells in cancer metastasis. To investigate the contribution of sialylated carbohydrate antigen, SPan-1, and sialic acid to the adhesion of human colon cancer cells to endothelial cells, adhesion assay using HUVECs (human umbilical vein endothelial cells) was performed. The adhesion was significantly inhibited by pretreatment with anti-E-selectin antibody, indicating that this adhesion was thought to be mediated by E-selectin. When these cancer cells were pretreated with SPan-1 antibody, the adhesion was significantly inhibited in a concentration-dependent manner. The adhesion was also inhibited by pretreatment with neuraminidase. These findings suggest that the SPan-1 antigen plays a significant role in the adhesion of human colon cancer cells to endothelial cells, and sialylation of the terminal structure of carbohydrate antigens is important in this adhesion.

Calcium efflux from cultured bovine adrenal chromaffin cells induced by pituitary adenylate cyclase-activating polypeptide (PACAP): possible involvement of an Na+/Ca2+ exchange mechanism

The effect of pituitary adenylate cyclase-activating polypeptide 1-38 (PACAP1-38) on Ca2+ efflux from cultured bovine adrenal chromaffin cells was examined. PACAP1-38 stimulated the efflux of 45Ca2+ from the cells in a concentration dependent manner (10(-9)-10(-7)M). This effect was inhibited by its potent receptor antagonist PACAP6-38. PACAP1-38 increased the formation of [3H]inositol phosphates and cyclic AMP in the cells. Forskolin, an activator of adenylate cyclase, also stimulated the efflux of 45Ca2+ from the cells. 3-Isobutyl-1-methylxanthine (IBMX), an inhibitor of phosphodiesterase, enhanced PACAP1-38-induced 45Ca2+ efflux from the cells. Phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C, had no effect on the efflux of 45Ca2+ from the cells. The increases in 45Ca2+ efflux induced by PACAP1-38 and forskolin were reduced by deprivation of extracellular Na+ and the Na+/Ca2+ exchange inhibitor amiloride. In addition, PACAP1-38 stimulated 22Na+ influx into the cells, and this action was inhibited by amiloride. These results suggest that PACAP1-38 stimulates an Na+/Ca2+ exchange mechanism through activation of adenylate cyclase in cultured bovine adrenal chromaffin cells.

D2 receptors in the ventrolateral striatum are involved in feeding behavior in rats

To study the role of dopamine D1 and D2 receptors in the ventrolateral striatum in feeding behavior, a D1 receptor agonist (CY 208-243), a D1 receptor antagonist (SCH 23390), a D2 receptor agonist (quinpirole), and a D2 receptor antagonist [(-)-sulpiride] were perfused via a microdialysis probe into the ventrolateral striatum of rats fasted for 22 h. Then the rats were allowed to feed freely for 6 h. Sulpiride perfusion at a high concentration suppressed food and water intake significantly, whereas dopamine release and the levels of DOPAC and HVA were increased at all concentrations. In contrast, quinpirole perfusion at a high concentration increased food intake by 41%. Dopamine release and the levels of DOPAC and HVA were decreased at all concentrations. On the other hand, neither CY 208-243 nor SCH 23390 changed food intake or dopamine release, but both drugs decreased water intake. These results suggest that D2 receptors in the ventrolateral striatum have a more important role than D1 receptors in the feeding behavior of rats.

Regulation of adipocyte gene expression by retinoic acid and hormones: effects on the gene encoding cellular retinol-binding protein

Our laboratory has reported that adipose tissue and adipocytes are importantly involved in retinoid storage and metabolism. To gain further insight, we examined factors that may regulate CRBP mRNA levels in primary cultures of rat epididymal and murine BFC-1 beta adipocytes. Northern blot analysis revealed that retinoic acid is a potent inducer of CRBP mRNA, causing a 7.5-fold rise in mRNA levels in primary adipocytes and a 9.5-fold rise in BFC-1 beta adipocytes. This induction of CRBP mRNA was dose-dependent at retinoic acid concentrations ranging between 10(-8) and 10(-5) M. Retinoic acid induction of CRBP mRNA levels showed a short lag period (6 h) and reached a maximal level of induction by 12 h in BFC-1 beta adipocytes and by 48 h in primary epididymal adipocytes. Nuclear run-on transcription assays of retinoic acid-induced BFC-1 beta adipocytes indicated that the rate of CRBP gene transcription is enhanced 3.6- to 4.3-fold by retinoic acid. In contrast, dexamethasone markedly down-regulated CRBP expression in a dose-dependent manner at concentrations ranging between 10(-9) and 10(-6) M. CRBP mRNA levels in primary and BFC-1 beta adipocytes declined, respectively, by 90% and 80% when adipocytes were exposed to 10(-6) M dexamethasone for 24 h. Studies of mRNA half-life indicated that dexamethasone acts to lessen CRBP expression through the specific destabilization of CRBP mRNA. Treatment of both primary and BFC-1 beta adipocytes with triiodothyronine alone had no effect on CRBP mRNA levels; however, when adipocytes were treated with a mixture of triiodothyronine and retinoic acid, the induction of CRBP mRNA levels by retinoic acid was reduced. In summary, these studies indicate that CRBP gene expression is regulated by retinoic acid, dexamethasone, and triiodothyronine; thus suggesting that retinol uptake, intracellular transport, and metabolism are dynamically regulated in adipocytes.

Stimulatory effect of angiotensin II on calcium efflux from cultured bovine adrenal chromaffin cells

The effect of angiotensin II on Ca2+ mobilization in cultured bovine adrenal chromaffin cells was examined. Angiotensin II (10(-7)M) increased the intracellular free Ca2+ level ([Ca2+]i) to a peak in the presence or absence of extracellular Ca2+, followed by decrease with time. Angiotensin II (10(-9)-10(-6)M) also stimulated 45Ca2+ efflux from cultured bovine adrenal chromaffin cells in a concentration-dependent manner. Its stimulatory effect on 45Ca2+ efflux was inhibited by the angiotensin II antagonist [Sar1, Ile8]-angiotensin II or [Sar1, Val5, Ala8]-angiotensin II. The increase in angiotensin II-stimulated 45Ca2+ efflux was dependent on the extracellular Na+ concentration. Angiotensin II also increased 22Na+ influx into the cells. These results indicate that stimulation of the angiotensin II receptor induces extracellular Na(+)-dependent Ca2+ efflux from cultured bovine adrenal chromaffin cells, probably by acceleration of Na+/Ca2+ exchange.

Alterations of O-glycan biosynthesis in human colon cancer tissues

Human colon cancer is associated with antigenic and structural changes in mucin-type carbohydrate chains (O-glycans). To elucidate the control of the biosynthesis of these O-glycans is colon cancer, we have studied glycosyltransferase and sulphotransferase activities involved in the assembly of elongated O-glycan structures. We analysed homogenates prepared from cancer tissue, adjacent normal and distal normal tissue from 20 patients. Several transferase activities showed pronounced changes in cancer tissue. The changes correlate with previous findings of a loss of O-glycans in cancer mucins, but did not always correlate with levels of Tn, sialyl-Tn, T and Lex antigens in homogenates or with the differentiation status and Duke's stages of the cancer tissue or the patient's blood type, sex and age. UDP-GlcNAc: Gal NAc-R beta 3-N-acetylglucosaminyltransferase (where GlcNAc is N-acetyl-D-glucosamine and GalNAc is N-acetyl-D-galactosamine) synthesizing O-glycan core 3, GlcNAc beta 1-3GalNAc-, CMP-sialic acid: GalNAc-peptide alpha 6-sialyltransferase synthesizing the sialyl-Tn antigen and sulphotransferase activities towards O-glycan core 1, Gal beta 1-3GalNAc-, were found to be decreased in cancer. UDP-GlcNAc: Gal beta 1-3GalNAc beta 6-N-acetylglucosaminyltransferase was also decreased in cancer concomitant with a loss of the ability to synthesize the I antigen and core 4, GlcNAc beta 1-6(GlcNAc beta 1-3) GalNAc-, CMP-sialic acid: Gal beta 1-3GalNAc-R alpha 3-sialyltransferase and GDP-fucose: Gal beta-R alpha 2-fucosyltransferase, synthesizing the blood group H determinant, were found to be 4- and 3- to 8-fold increased, respectively, in cancer compared to normal tissue. The data suggest that the biosynthesis of antigens and mucin-bound O-glycan structures in colon cancer is subject to complex control mechanisms.

Mechanism of histamine-induced calcium efflux from cultured bovine adrenal chromaffin cells: possible involvement of an Na+/Ca2+ exchange mechanism

The effect of stimulation of the histamine receptor on Ca2+ mobilization in cultured bovine adrenal chromaffin cells was examined. Histamine (10(-5) M) increased the intracellular free Ca2+ ([Ca2+]i) to a peak in the presence or absence of extracellular Ca2+, followed by decrease with time. Histamine (10(-8)-10(-5) M) also stimulated 45Ca2+ efflux from cultured bovine adrenal chromaffin cells in a concentration dependent manner. Its stimulatory effect on 45Ca2+ efflux was inhibited by the specific histamine H1 receptor antagonist mepyramine. The increase in histamine-stimulated 45Ca2+ efflux was inhibited by deprivation of extracellular Na+ and by the Na+/Ca2+ exchange inhibitor amiloride. In addition, histamine stimulated 22Na+ influx into the cells, and this action was inhibited by amiloride. These results suggest that stimulation of the histamine H1 receptor regulates Na+/Ca2+ exchange in cultured bovine adrenal chromaffin cells.

A new cancer-associated antigen defined by a monoclonal antibody against a synthetic carbohydrate chain

Carbohydrate antigens can be designed by referring to previously defined carbohydrate structures. We have generated a novel monoclonal antibody (MAb) (F1 alpha-75) against an artificially designed antigen (F1 alpha), using organic-synthetic chemistry methods and hybridoma technology. F1 alpha (Gal beta 1-->4GlcNAc beta 1-->6GalNAc alpha 1-->Ser/Thr) belongs to core type 6 of O-linked glycans, which has not been previously reported in human cancers. To produce antibodies against F1 alpha, a glycolipid was synthesized which carries the carbohydrate portion of F1 alpha on a ceramide foundation (Gal beta 1-->4GlcNAc beta 1-->6GalNAc alpha 1-->Cer). The MAbs we obtained (F1 alpha-75, F1 alpha-87) specifically recognized F1 alpha and had only a very weak or no cross-reactivity with other glycolipids similar to F1 alpha. We investigated the expression of F1 alpha in human tissues, including 110 gastric cancers, 73 colon cancers and 42 pancreatic cancers. F1 alpha was found in human cancerous tissues but not in normal adult tissues. The rate of positive staining with F1 alpha-75 was 80.0% for gastric cancer, 52.4% for pancreatic cancer and 38.4% for colon cancer. F1 alpha-75 also reacted with the tissues neighboring gastric and pancreatic tumors but not intensely. Among fetal tissues, F1 alpha-75 reacted with the pyloric glands of the stomach, the centro-acinar cells of the pancreas, the convoluted tubules of the kidney and the terminal bronchioles of the lung.

[A cohort study on dental caries in infants]

A cohort study was performed to determine what techniques are effective in dental caries prevention in infants. Subjects were 878 children aged 18 months, who visited the Gifu-shi Central Public Health Center to receive the medical health check and who were found to be dental caries free. The subjects received both 18 months and 3 years old dental health examinations which included data on incidence of dental caries and oral hygiene conditions (plaque score). Information on the children's between-meals eating habits and mother aided daily tooth brushing habits were obtained from their mothers. Caries incidence was 31.5% and 43.3% in children with good and poor oral hygiene conditions, 30.9% and 38.5% in children with and without daily brushing habits, and 41.0% and 29.2% in children with and without between-meals eating habits, respectively. Logistic regression analysis indicated that oral hygiene conditions and eating habits between meals were more important than mother aided daily tooth brushing.

Analysis of flagellar bending in hyperactivated hamster and mouse spermatozoa

Flagellar bending was analysed using photographs of hyperactivated hamster and mouse spermatozoa. The flagellar waveform consists of several bends; the centre of each bend was therefore located on the flagellum, and the angle of the bend measured. The direction of the bend was determined by using the asymmetry of hook-shaped head to assess the asymmetry of flagellar waveform. The bend that occurred in the same direction as the curve of head was defined as the reverse bend and the bend in the opposite direction as the principal bend. In hamster spermatozoa, flagellar bending was asymmetric to the direction of the reverse bend after incubation for 5 min. After incubation for 4 h the asymmetry had increased, as the angles of the reverse bends had increased in all regions of the flagellum but the principal bend had not. In mouse spermatozoa incubated for 5 min, flagellar bending was relatively symmetric. In the hyperactivated mouse spermatozoa incubated for 3 h, the angle of the principal bend increased in the distal region and those of the reverse bends increased in almost all regions of the flagellum. Since the increase in the reverse bend was relatively high, flagellar bending became asymmetric to the direction of the reverse bend as in hamster spermatozoa. These increases in asymmetry were also evident in the measurement of the total changes in angular direction between the proximal and distal end of flagella in both species. The increase in asymmetry could provide an explanation for the changes in the motility patterns seen in spermatozoa after the onset of hyperactivation.(ABSTRACT TRUNCATED AT 250 WORDS)

Modulation of collagen synthesis and degradation by retinoids and cytokines in 3T3 L1 preadipocytes

We previously observed that a retinoid analog can protect against liver parenchymal damage and liver fibrosis, whereas it accelerates liver fibrosis which is not accompanied by any parenchymal damage. To elucidate these conflicting effects, we examined the effects of retinoid in 3T3 L1 preadipocytes as a model of liver stellate cells. Retinoids, including all-trans retinol, all-trans and 9-cis retinoic acids, enhanced the cell growth and the expression of the type I procollagen gene as well as its peptide synthesis, while reducing collagenase activities. Although no retinoid enhanced the transforming growth factor (TGF)-beta 1 mRNA, retinoids may stimulate collagen production through activating TGF-beta, as was recently reported. These results help explain the observation in the liver fibrosis model with no parenchymal damage. In contrast, we also found that interferon (IFN) alpha beta and gamma inhibited cell growth and down-regulated markedly type I procollagen as well as TGF-beta 1 mRNA, suggesting that they suppress by acting directly on extracellular matrix-producing cells.

Fibroblast attachment to Arg-Gly-Asp peptide-immobilized poly(gamma-methyl L-glutamate)

The attachment of MRC-5 human fibroblasts was investigated on poly(gamma-methyl L-glutamate) (PMLG), and upon cell adhesion peptides Arg-Gly-Asp-Ser (RGDS)- and Gly-Arg-Gly-Asp-Ser (GRGDS)-immobilized PMLG (RGDS-PMLG and GRGDS-PMLG). The peptides were immobilized by their N-terminal amine to activated PMLG surfaces. Prior to peptide immobilization, the aminolysis of PMLG surfaces was performed with hydrazine hydrate (HA), ethylenediamine (EDA), and hexamethylenediamine (HMDA) and was followed by the activation with hexamethylene diisocyanate. Surface characterization of these films was carried out by means of a Fourier transform IR (FT-IR) spectrometer equipped with an attenuated total reflectance (ATR) attachment. The amount of immobilized RGDS could be controlled by the reaction time of the aminolysis. The effects of HA, EDA, and HMDA as a spacer on the cell attachment were also investigated, and it was suggested that a longer spacer promoted the cell attachment via specific receptor-ligand interaction.

Behavior of Japanese tree frogs under microgravity on MIR and in parabolic flight

Japanese tree frogs (Hyla japonica) were flown to the space station MIR and spent eight days in orbit during December, 1990. Under microgravity, their postures and behaviors were observed and recorded. On the MIR, floating frogs stretched four legs out, bent their bodies backward and expanded their abdomens. Frogs on a surface often bent their neck backward and walked backwards. This behavior was observed on parabolic flights and resembles the retching behavior of sick frogs on land--a possible indicator of motion sickness. Observations on MIR were carried out twice to investigate the frog's adaptation to space. The frequency of failure in landing after a jump decreased in the second observation period. After the frogs returned to earth, readaptation processes were observed. The frogs behaved normally as early as 2.5 hours after landing.

Case of Williams elfin facies syndrome with pulmonary artery sling

We report the presence of pulmonary artery sling in a 4-year-old girl with the Williams elfin facies syndrome. A history of heavy and persistent wheezing during the first few months of life, associated with the current presentation of heart murmur and pulmonary stenosis, led us to investigate the presence of pulmonary artery sling. Both pulmonary artery sling and cardiovascular anomalies in Williams elfin facies syndrome have previously been linked to developmental anomalies of the 6th aortic arch. This appears to be the second reported case of this rare combination of anomalies.

[Clinical evaluation of a lung cancer-associated protein antigen, cytokeratin 19 fragment: II. Radioimmunoassay and effect of aging and smoking over serum level of normal individuals]

Serum level of cytokeratin 19 fragment which is a tumor associated antigen of lung cancer was detected by the radioimmunometric assay. Effect of smoking and of aging on serum reference value was analyzed over 331 normal individuals. Serum cytokeratin 19 fragment level of smokers, mean 0.89ng/ml, was higher than that of non-smokers, mean 0.70ng/ml although there was no statistical meaning over the difference. And there was tendency to increase of cytokeratin 19 fragment level with aging. Mean + 2SD of cytokeratin 19 fragment of normal was 2.17ng/ml. Clinico-epidemiological specificity of cytokeratin 19 fragment on normal individuals was discussed.

[Clinical evaluation of a lung cancer-associated protein antigen, cytokeratin 19 fragment: I. Radioimmunoassay and its fundamental character for clinical laboratory measurement]

Serum level of cytokeratin 19 fragment; which is a tumor associated antigen of lung cancer; was detected by the radioimmunometric assay. Reliability for clinical laboratory measurement was investigated. Detective range of cytokeratin 19 fragment was 0-50 ng/ml and the results including reproducibility, linearity of the data from diluted standard samples, was good enough for laboratory practice use. Although, influence of high concentration of CA19-9 over cytokeratin 19 fragment assay was suspected, there was no correlation between amount of added the antigen to data of cytokeratin 19 fragment. So direct cross reactivity of cytokeratin 19 fragment antibody to CA19-9 seemed less possible. As inhibitory effect of samples which contained over 100 ng/ml of cytokeratin 19 fragment on assay was observed due to antigen excess, evaluation by diluted sample was necessary for the samples that showed over detective limit.

The sliding of the fibrous sheath through the axoneme proximally together with microtubule extrusion

When activated mouse sperm were treated with Triton X-100 and dithiothreitol at pH 9.0, the plasma membrane and mitochondrial sheath of the sperm flagella were removed. These mitochondrion-free demembranated sperm flagella were perfused with Mg-ATP and trypsin to induce the sliding disintegration of microtubules from the axoneme. We observed that when the doublet microtubules associated with outer dense fibers extruded from the axoneme, the fibrous sheath (FS) was pulled proximally to the connecting piece from the annulus of the sperm flagellum accompanying the extrusion of microtubules. Furthermore, the FS sliding was cAMP-dependent and the maximal sliding velocity was about 3.7 +/- 0.1 microns/s in the presence of 1.0 mM ATP at 37 +/- 1 degrees C. Since the FS projected inward and attached opposite doublet microtubules 3 and 8 in the principal piece, our observation showed the possibility that doublet 3 and/or 8 participated in FS sliding.

Multiple activation of mouse sperm motility

To investigate the activation mechanism of mouse sperm motility, the intact sperm in various activities were further investigated after demembranation. When dry sperm was diluted into sucrose solution, the sperm exhibited low motility with the swimming velocity of 13.5 +/- 3.8 microns/s and the beat frequency of 1.5 +/- 0.4 Hz. The demembranated sperm were immotile in the reactivation solution lacking cAMP. Meanwhile, when dry sperm was diluted into the solution containing either high concentration of NaCl or Ca2+, they exhibited the beat frequency of about 9 Hz. The demembranated ones exhibited the intermediate motility in the absence of cAMP. When dry sperm were diluted into the sucrose solution containing HCO3-, the sperm exhibited a vigorous motility with the swimming velocity of 181.2 +/- 10.1 microns/s and the beat frequency of 11.3 +/- 1.2 Hz. The demembranated sperm exhibited the high reactivation motility (90%) and flagellar beat frequency (9 Hz) in the absence of cAMP. These values were almost equivalent to those obtained in the demembranated sperm pretreated with sucrose or Ca2+ or NaCl and reactivated in the presence of cAMP. The activation induced by bicarbonate was considered complete in comparison with the activation by Ca2+ or NaCl. It was likely that the activation of mouse sperm motility took multiple states.

A single-blind comparison of bromperidol and sulpiride in hospitalized schizophrenics

Fourty-five schizophrenic inpatients were randomly assigned to bromperidol or sulpiride in an 8 week single-blind clinical trial. No statistically significant differences were observed for final global improvement rating. Regarding BPRS items and compared to sulpiride, bromperidol was particularly effective to relieve emotional withdrawal and hallucinatory behavior, although the only significant between group difference was in favour of sulpiride for improvements of somatic concern. No significant differences were observed for all PES items, although sulpiride was found more effective for hypochondriasis and neurotic complaint as was bromperidol for hallucination and disturbance of self-conscious. The rate of side-effects and abnormal laboratory test results were comparable in the two groups. They were not severe enough to require termination of administration. Bromperidol and sulpiride are concluded to have different clinical profile in the treatment of schizophrenic hospitalized patients.

[Analysis of bone loss with aging and menopause--using digital image processing]

To study bone loss relationships to aging and menopause, cross-sectional bone mass measurements by digital image processing (DIP method), and menopause information collected by questionnaire, were analyzed on 291 women who live in Tsukude village. The results are as follows. 1) The mean DIP values (sigma GS/D, MCI) by age-stratified groups decrease with age after menopause. The rate of bone loss in sigma GS/D is almost constant, but in MCI it increases with aging. 2) In 30-year old and 40-year old age groups, the frequency distribution of DIP values is symmetrical and bell-shaped. But after the fifties the distribution is asymmetrical, with the mode of distribution deviated toward low bone mass. The change of mode with aging is larger than that of mean. This fact suggests that change of mean bone mass substantially underestimates actual bone loss from aging. 3) The change of the mean DIP values stratified by years elapsed since menopause is not especially large at start of menopause but becomes almost constant after menopause. DIP values reflect the bone loss from the aging rather than from menopause, and are beneficial to the study of bone loss in elderly women.

Effect of endothelin 1 on ion transport in isolated rat colon

BACKGROUND

Endothelin may play a significant role in the regulation of gastrointestinal function because it has a variety of biological activities and because endothelin-like immunoreactivity as well as its specific binding sites have been found in the gastrointestinal tract. This study investigated the secretory effect and mechanism of action of endothelin 1 in mammalian large intestine.

METHODS

Distal colonic segments from Sprague-Dawley rats were stripped of their muscle layers and mounted in Ussing chambers. The effects of endothelin 1 on short-circuit current in rat colonic mucosa were studied in the absence or presence of specific inhibitors. Transmural unidirectional 22Na+ and 36Cl- fluxes and endothelin 1-induced prostacyclin release were also measured.

RESULTS

Serosal addition of endothelin 1 evoked a sustained increase in short-circuit current that was significantly reduced by tetrodotoxin or atropine, and virtually abolished by a selective endothelin A receptor antagonist (BQ-123), furosemide, piroxicam, d,I-verapamil, or removal of serosal calcium. Hexamethonium, amiloride, diphenhydramine, or a specific platelet-activating factor antagonist (CV-6209) did not influence the response to endothelin 1. Endothelin 1 significantly decreased net sodium and net chloride absorption and induced a marked increase in prostacyclin release from the serosal surface of stripped colonic mucosa.

CONCLUSIONS

Endothelin 1 has a secretory effect in rat colon. Its action seems to be mediated by cyclo-oxygenase products and enteric nerves via the activation of an endothelin A receptor.

[Cellular retinoid-binding proteins]

This paper will review the function of cellular retinoid-binding proteins and receptors (RAR), especially to address recent works on cellular uptake, intracellular transport, biosynthesis and metabolism of retinoids. Cellular retinol-binding protein (CRBP) binds retinol and retinal, cellular retinoic acid-binding protein (CRABP) binds retinoic acid, both of which have a molecular weight of 16 kDa, and cellular retinal-binding protein (CRALBP) binds retinal with a molecular weight of 36 kDa. CRBP (I) functions in cellular uptake of retinol from the plasma, solubilizes and renders retinol nontoxic in the aqueous system, and presents retinol to the appropriate enzymes to biosynthesize retinoic acid (an active form of retinoids) or retinyl esters (a storage form). CRBP (II) mainly distributes in the absorptive cell in the small intestine and functions in absorption of retinoids and carotenoids to biosynthesize retinyl esters present in the chylomicron. CRBP (III) is recognized as one of oncofetal proteins and binds both retinol and retinoic acid, the function of which still remains unclear. CRABP (I), previously recognized as a transport protein of retinoic acid to the nucleus, is now assumed to sequester retinoic acid from retinoic acid receptor(s) in the tissue where retinoic acid levels are required to be low. CRABP (I) also functions in the catabolism of retinoic acid to modulate its concentration in the cell. CRABP (II), expressed in the developmental stage of the fetus, is suggested to modulate the action of retinoic acid as a 'morphogen'.

Roles of pH and cyclic adenosine monophosphate in the acquisition of potential for sperm motility during migration from the sea to the river in chum salmon

In the natural process of the migration of chum salmon from the sea to the river, spermatozoa moved from the testis to the sperm duct, and the pH value of seminal plasma, concentration of cyclic adenosine monophosphate (AMP) in the sperm cells, and potential for sperm motility increased. Cyclic AMP levels and the potential for motility gradually increased when testis spermatozoa with no capacity for movement were incubated in the artificial seminal plasma of which the pH was much the same as, or higher than, the pH of natural seminal plasma from the sperm duct. Such correlation in motility, pH, and cyclic AMP suggests that the increases in seminal pH and intracellular cyclic AMP level during passage of spermatozoa from the testis to the sperm duct cause the acquisition of potential for motility. Motility of testicular spermatozoa demembranated with Triton X-100 was very low in fish caught in the sea, while motility of spermatozoa from the posterior portion of the sperm duct was much higher in fish caught in the river. Furthermore, nondemembranated, intact spermatozoa showed a lag in the timing of the acquisition of potential for motility vs. demembranated spermatozoa: The demembranated sperm exhibited the potential earlier than the nondemembranated sperm. These data suggest that increase in activity of the motile apparatus, the axoneme, is a prerequisite, in part, for the acquisition of sperm motility, whereas the development of some function of the plasma membrane also contributes to this phenomenon.

No effects of smoking or drinking habits on salivary amylase

Nonstimulated and expectorated whole saliva was collected from 166 males and 180 females. To investigate biological effects of smoking and drinking habits on digestive functions in healthy populations, salivary total proteins and amylase activity were determined in the saliva samples. Sex differences in the salivary components were not found. Neither of the two habits had any significant influences on salivary proteins or amylase activity in the subjects. Light to moderate uses of tobacco or alcohol may not influence basal components of saliva.

Scheduled feeding caused activation of dopamine metabolism in the striatum of rats

The effects of a time-restricted feeding schedule on dopamine (DA) release and its metabolites output in the striatum of freely moving rats were studied. Rats had access to food for only 2 h daily for 7 successive days. On the 1st or 7th day, the extracellular concentrations of DA, 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in the ventrolateral striatum were measured by in vivo brain microdialysis during 2 h of exposure to food-related stimuli followed by 2 h of access to food. Extracellular concentrations of DA and its metabolites did not change during the period of exposure to food-related stimuli or during feeding on the 1st day. On the 7th day, extracellular DOPAC and HVA concentrations increased significantly during 2 h of feeding, but not during exposure to food-related stimuli, compared with basal levels. Extracellular DA concentration did not change significantly. These results indicate that scheduled feeding caused activation of DA metabolism in the ventrolateral striatum and facilitate feeding-related motor activity in feeding behavior.

Cell-attachment activities of surface immobilized oligopeptides RGD, RGDS, RGDV, RGDT, and YIGSR toward five cell lines

Tetrapeptides, Arg-Gly-Asp-Ser (RGDS), Arg-Gly-Asp-Val (RGDV), and Arg-Gly-Asp-Thr (RGDT), respectively, appearing in the cell-attachment domains of fibronectin, vitronectin, and collagen, and pentapeptide Tyr-Ile-Gly-Ser-Arg (YIGSR) appearing in B1 chain of laminin, were synthesized by liquid-phase procedure. Bioactivities of RGD, RGDX (X = S, V and T), YIGSR, and YIGSR-NH2 as cell recognition determinants were investigated by cell-attachment test using these oligopeptides immobilized to ethylene-acrylic acid copolymer (PEA) film. The cell lines used were A431, NRK, CHO-K1, HeLa.S3, and RLC-16 cells. It was found that the residue X in RGDX plays an important role for cell-attachment activity of RGDX, and, regarding YIGSR, introduction of NH2 residue at the C-terminal of the pentapeptide enhances the cell-attachment activity.

The clearance rate of chylomicron retinyl ester from plasma can be used to distinguish rats with cirrhosis from those with portacaval shunt

Effects of carbon tetrachloride treatment and portacaval shunt surgery on exogenous chylomicron retinyl ester clearance from rat plasma were analyzed assuming three-compartment model kinetics. In rats with cirrhosis and in those with Eck fistulas, the relative pool size of compartment 2 decreased (0.20 and 0.36, respectively) compared with controls (0.82). The relative mass of compartment 3 significantly increased in rats with cirrhosis (1.55) or Eck fistula (0.19) compared with control rats (0.11). The cirrhotic and Eck fistula groups were indistinguishable on the basis of these parameters and on the basis of indocyanine green test values. However, the cirrhosis and Eck fistula groups differed clearly from each other with respect to fractional efflux rate constants (l2, l3), where the constant l2 is from compartment 2 and the l3 is from compartment 3. Both values decreased in cirrhotic rats, suggesting that the hepatic uptake of chylomicron retinyl esters was impaired by carbon tetrachloride. On the other hand, Eck fistula rats did experience dramatic increases in l3, implying that the hepatic uptake of chylomicron retinyl esters from compartment 3 was enhanced by portacaval shunting. Elevation of the plasma estrogen level observed in Eck fistula rats may be responsible for the induction of low-density lipoprotein receptors on hepatocytes and for the subsequent enhancement of l3. These results suggest that a three-compartment model of plasma retinyl ester disappearance kinetics gives important quantitative information about hepatic function. Clinical application of the chylomicron retinyl ester clearance test is discussed for estimating hepatic function reserves and for differential diagnosis of portal hypertension.

Reduced bone density and major hormones regulating calcium metabolism in anorexia nervosa

Bone density of lumbar vertebrae (L2 to L4) and the whole body in 29 patients with anorexia nervosa were measured by dual photon absorptiometry, and the results were compared with those of 10 age-matched normal controls. The patients had significantly lower bone mineral density (BMD) in L3 and L2-4 than controls. However, there was no difference in whole-body BMD. L3 and L2-4 BMD was positively correlated with body weight and was negatively correlated with duration of illness and amenorrhea. Patients who had been more active 6 months before the time of the study had significantly higher L3 BMD than the less active patients. Most patients had an abnormally low serum estrogen level, whereas the mean serum levels of thyroid hormone (T3, T4), cortisol, calcitonin, parathyroid hormone and vitamin D were within the normal range. No correlation was found between L3 or L2-4 BMD and the levels of these hormones. These results suggest that severe weight loss, low physical activity, longer duration of amenorrhea and deficiency of estrogen contribute to bone loss in patients with anorexia nervosa, whereas calcium-regulating hormones such as parathyroid hormone, calcitonin and vitamin D are unlikely to be a primary contributor to bone loss.

[Determination and clinical significance of human hepatocyte growth factor in serum]

Hepatocyte growth factor (HGF) is the most potent mitogen for mature parenchymal hepatocytes in primary culture, and seems to be a hepatotrophic factor that acts as a trigger for liver regeneration after partial hepatectomy and liver injury. In the present study, we evaluated an enzyme-linked immunosorbent assay, using monoclonal antihuman HGF (h-HGF) antibody, for measuring serum h-HGF levels. Intra- and inter-assay coefficients of variation were 2.2-3.3% and 3.4-4.0%, respectively. Detection limit of this method was 0.1 ng/ml, determining by the dilution test. The substances tested did not interfere with this assay, except for high concentrations of hemoglobin. Furthermore, no interference was observed with plasminogen and lipoprotein (a), which show the structural homology to h-HGF, and with various kinds of cytokines. Reference ranges of serum h-HGF determined with 187 healthy subjects were 0.1-0.23 ng/ml. Serum h-HGF concentrations were increased in various kinds of liver diseases, in particular those were significantly higher in fulminant hepatic failure. Furthermore, prognosis of the patients with higher h-HGF values were strikingly worse than those with lower levels. We concluded that the determination of serum h-HGF plays important roles in the early diagnosis and prognosis of fulminant hepatic failure.

Galanin-induced alteration of electrolyte transport in the rat intestine

Effects of rat and porcine galanin on rat intestinal ion transport were examined in vitro. In the rat distal colon, a sustained increase in short-circuit current (Isc) was produced by the serosal addition of rat galanin at a concentration as low as 10(-9) M, and a maximal increment was observed at 10(-7) M. Porcine galanin was approximately 100 times less potent than rat galanin. In the rat jejunum, rat galanin produced only a slight and transient decrease in basal Isc. The response to rat galanin was not influenced by atropine, hexamethonium, or amiloride, but was virtually abolished by tetrodotoxin or furosemide. Rat galanin did not significantly influence the increase in Isc elicited by electrical field stimulation in the rat colon and jejunum. Transmural unidirectional 22Na and 36Cl fluxes in the rat colonic mucosa were measured under short-circuited conditions, and rat galanin significantly decreased net sodium and net chloride absorption. These findings suggest that galanin acts as a secretory modulator in the rat colon via noncholinergic neural transmission.

Differentiation-dependent expression of retinoid-binding proteins in BFC-1 beta adipocytes

Recently, we demonstrated that adipose tissue plays an important role in retinol storage and retinol-binding protein (RBP) synthesis. Our data suggested that RBP expression in adipose tissue is dependent on the state of adipocyte differentiation. To examine this possibility, we explored the differentiation-dependent expression of RBP using BFC-1 beta preadipocytes, which can be stimulated to undergo adipose differentiation. Total RNA was isolated from undifferentiated (preadipocytes) and differentiated (adipocytes) BFC-1 beta cells and analyzed by Northern blotting. RBP mRNA was not detected in the preadipocytes, but considerable RBP mRNA was present in differentiated BFC-1 beta cells. In BFC-1 beta cells, induced to differentiate with insulin and thyroid hormone, RBP mRNA was first detected after 4 days, reached a maximum level by day 10, and remained at this maximum level for at least 2 more days. Cellular retinol-binding protein was expressed at low levels in the BFC-1 beta preadipocytes and the level of expression increased for 6 days after induction to differentiate and slowly declined on later days. Neither the maximum level of RBP expression nor the day on which this level was reached was influenced by the level of retinol provided in the BFC-1 beta culture medium. BFC-1 beta cells secreted newly synthesized RBP into the culture medium at a rate of 43 +/- 14 ng RBP/24 h/10(6) adipocytes. When the BFC-1 beta adipocytes were provided 1.0 microM retinol in the medium, they accumulated the retinol and synthesized retinyl esters. These studies with BFC-1 beta cells confirm that RBP synthesis and secretion and retinol accumulation are intrinsic properties of differentiated adipocytes. Furthermore, they suggest that RBP and cellular retinol-binding protein gene expression are regulated as part of a package of genes which are modulated during adipocyte differentiation.

Separation of X- and Y-chromosome-bearing murine sperm by free-flow electrophoresis: evaluation of separation using PCR

The effectiveness of separation of murine X- and Y-bearing sperm by free-flow electrophoresis was evaluated by the polymerase chain reaction (PCR). The ratio of X- and Y-bearing sperm from cauda epididymis was analyzed before and after free-flow electrophoresis. A Y-chromosome-specific sequence (pY353/B) and an autosomal sequence (myogenin) were used to estimate the ratio between X- and Y-sperm in the separated fractions. Cauda epididymal mice sperm were separated into two peak fractions under the electric field. Each peak fraction contained sperm of normal shape, however, the motility of the sperm was extremely diminished after separation by electrophoresis. DNA was extracted from 10(4) sperm from each fraction and from the unseparated sperm, and Y-chromosome specific PCR was performed. The PCR experiment revealed that fraction No. 16 (the peak near the cathode) was a Y-sperm rich fraction, whereas fraction No. 22 (the peak near the anode) was a Y-sperm poor one. These results suggested that murine X- and Y-sperm could be successfully separated by free-flow electrophoresis. Analysis of the chromosome-specific sequence by PCR was demonstrated to be a direct and adequate method to evaluate the separation of X- and Y-sperm.

Analysis of tubulin isoforms by two-dimensional gel electrophoresis using SDS-polyacrylamide gel electrophoresis in the first dimension

A two-dimensional electrophoretic system using SDS-polyacrylamide gel electrophoresis (SDS-PAGE) in the first dimension and isoelectric focusing (IEF) in the second dimension was devised. In spite of its simplicity, this method could show a markedly high resolution for tubulin isoforms and moreover could classify them into alpha- or beta-tubulin as a two-dimensional profile. With this method, seven alpha- and four beta-tubulin isoforms could be detected within axoneme from Tetrahymena cilia. Moreover this method could also resolve tubulin isoforms from the rabbit brain. These results indicate that the present two-dimensional gel electrophoresis is a useful tool for the electrophoretic analysis of tubulin isoforms from various sources.

Retinoids and retinoid-binding protein expression in rat adipocytes

Adipose tissue has been reported to contain relatively high levels of the specific mRNA for retinol-binding protein (RBP) (Makover A., Soprano, D.R., Wyatt, M. L., and Goodman, D.S. (1989) J. Lipid Res. 30, 171-180). Studies were conducted to explore retinoid and retinoid-binding protein storage and metabolism in adipose tissue. In these studies, we measured RBP and cellular retinol-binding protein (CRBP) mRNA levels and retinoid levels in 6 adipose depots in male rats. Total RNA was isolated from inguinal, dorsal, mesenteric, epididymal, perinephric, and brown adipose tissue, and average RBP and CRBP mRNA levels were determined by Northern blot analysis. The relative levels of RBP mRNA in these 6 anatomically different adipose depots averaged, respectively, 6.3, 6.7, 16, 34, 37, and 21% of the level in a rat liver RNA standard. Retinoid levels in the 6 depots were similar and averaged approximately 6-7 micrograms of retinol eq/g of adipose tissue. Since adipose tissue contains several cell types, the cellular localizations of RBP and CRBP expression and retinoid storage were examined. RNA was prepared from isolated rat adipocytes and stromal-vascular cells. Cellular levels of the mRNAs for RBP, CRBP, apolipoprotein E (apoE), lipoprotein lipase, adipocyte P2, and adipsin were measured by Northern blot analysis. RBP was expressed almost exclusively in the adipocytes and only weakly in the stromal-vascular cells. Both CRBP and apoE mRNA levels were relatively high in the stromal-vascular cell preparations and only very low mRNA levels were found in the adipocytes. Lipoprotein lipase, adipsin, and adipocyte P2 mRNAs were found in substantial levels in both the adipocytes and stromal-vascular cells, but with higher levels present in the adipocytes. Cultured adipocytes synthesized RBP protein and secreted it into the medium. Only adipocytes (not stromal-vascular cells) contained retinol, at levels between 0.65-0.8 micrograms of retinol eq/10(6) cells. These studies demonstrate that adipocytes store retinoid and synthesize and secrete RBP, and suggest that rat adipocytes may be dynamically involved in retinoid storage and metabolism.

Peptide YY enhances NaCl and water absorption in the rat colon in vivo

Peptide YY (PYY) is thought to possess paracrine and endocrine functions. The highest concentrations of this peptide are in the colonic mucosa. The effect of PYY on electrolyte and water transport in the rat colon was studied in vivo. Under urethane anesthesia, rat colonic loops were perfused at a constant rate with physiological buffer solution containing phenol red as a nonabsorbable volume marker, and net movements of water, sodium, chloride and potassium in the perfused colon were determined every 10 min. Intravenous administration of PYY produced a dose-dependent increase in the net absorption of sodium chloride and water, as well as a decrease in the net secretion of potassium. PYY inhibited the reduction in net absorption of sodium chloride and water evoked by vasoactive intestinal peptide (VIP), but did not affect the VIP-evoked increase in net potassium secretion. These findings suggest that PYY acts as an enhancer of sodium chloride and water absorption and as an antagonist to VIP-induced secretion in the colon.