Preventing postpartum depression using an educational video on infant crying

Background

Perception of and reactive behaviors towards infant crying is one of the modifiable risk factors for postpartum depression. The aim of this study was to examine the impact of watching an educational video on infant crying within 1 week of age after delivery at maternity wards to reduce the prevalence of postpartum depressive symptoms at 1 month after giving birth.

Methods

Study design was a cluster randomized controlled trial (UMIN000015558). The intervention hospitals were randomly assigned, stratified by area and function of the hospital. Participants included 47 obstetrics hospitals or clinics out of 150 hospitals or clinics in Osaka Prefecture, Japan. In total, 44 hospitals or clinics completed the trial and 2,601 (intervention group=1,040, control group=1,561) caregivers responded to the questionnaire on postpartum depression. Mothers in the intervention group watched a 11-minute educational video, within 1 week of age, during hospitalization at maternity wards. Primary outcome in this study was postpartum depression assessed by the Edinburgh Postnatal Depression Scale as 9+, and assessed via questionnaire at a 1-month health checkup.

Results

In the intervention group, 142 (13.7%) mothers reported postpartum depression compared to 250 (16.0%) in the control group. Intention-to-treat analysis showed no significant difference in the prevalence of postpartum depression between the groups. However, among young mothers (<25 years old), the analysis showed a 67% reduction in postpartum depression (OR:0.33, 95%CI:0.15-0.72).

Conclusions

Watching an educational video on infant crying did not reduce postpartum depression at 1 month after giving birth, but it was effective for young mothers aged less than 25 years old. It may be easier to introduce our approach to any opportunity for meeting mothers during perinatal period because it does not require specialized manpower and a significant amount of time for the intervention.

Key messages

The educational video on infant crying, “Baby Doesn't Stop Crying,” had no effect in preventing postpartum depressive symptoms. Among young mothers aged <25 years, the educational video had a protective effect on postpartum depressive symptoms, which was not observed for mothers aged ≥25 years.

Early Endosomal Trafficking Component BEN2/VPS45 Plays a Crucial Role in Internal Tissues in Regulating Root Growth and Meristem Size in Arabidopsis

Polar auxin transport is involved in multiple aspects of plant development, including root growth, lateral root branching, embryogenesis, and vasculature development. PIN-FORMED (PIN) auxin efflux proteins exhibit asymmetric distribution at the plasma membrane (PM) and collectively play pivotal roles in generating local auxin accumulation, which underlies various auxin-dependent developmental processes. In previous research, it has been revealed that endosomal trafficking components BEN1/BIG5 (ARF GEF) and BEN2/VPS45 (Sec1/Munc 18 protein) function in intracellular trafficking of PIN proteins in Arabidopsis. Mutations in both BEN1 and BEN2 resulted in defects in polar PIN localization, auxin response gradients, and in root architecture. In this study, we have attempted to gain insight into the developmental roles of these trafficking components. We showed that while genetic or pharmacological disturbances of auxin distribution reduced dividing cells in the root tips and resulted in reduced root growth, the same manipulations had only moderate impact on ben1; ben2 double mutants. In addition, we established transgenic lines in which BEN2/VPS45 is expressed under control of tissue-specific promoters and demonstrated that BEN2/VPS45 regulates the intracellular traffic of PIN proteins in cell-autonomous manner, at least in stele and epidermal cells. Furthermore, BEN2/VPS45 rescued the root architecture defects when expressed in internal tissues of ben1; ben2 double mutants. These results corroborate the roles of the endosomal trafficking component BEN2/VPS45 in regulation of auxin-dependent developmental processes, and suggest that BEN2/VPS45 is required for sustainable root growth, most likely through regulation of tip-ward auxin transport through the internal tissues of root.

Transient local overexpression of human vascular endothelial growth factor (VEGF) in mouse feto-maternal interface during mid-term pregnancy lowers systemic maternal blood pressure

The effect on maternal circulation of transient human vascular endothelial growth factor (VEGF) (165) cDNA transfection into the mouse feto-maternal interface at day 14.5 post coitus (p.c.) using a hemagglutinating virus of Japan-envelope (HVJ-E) vector system is reported. On day 15.5 p.c., Western blotting clearly showed overexpression of 18 kD VEGF protein in the uterus. After VEGF transfection, the blood pressure was significantly lowered for 48 hours. On day 17.5 p.c., the blood pressure returned to the control level. Proteinuria was not observed after VEGF transfection. No preterm birth was observed during the course of pregnancy after the transfection procedure. After 24 hours of transfection, human VEGF was not detectable and the mouse VEGF level was similar to that in peripheral blood. However, the soluble fms-like tyrosine kinase (Flt)-1 concentration was significantly lower in VEGF-transfected mice. These results suggest that extraamniotic VEGF overexpression lowered the systemic blood pressure without altering the VEGF concentration in the peripheral blood. Local overexpression of VEGF may become a novel treatment for pregnancy-related disorders such as hypertension complicated-pregnancy and preeclampsia.

The effect of a valine-rich diet on intestinal adaptation to massive small bowel resection in the rat

BACKGROUND/PURPOSE

Recently, valine, which is one of the branched chain amino acids, has been reported to enhance liver regeneration after hepatectomy in the rat. The aim of this study was to investigate the effect of enteral valine supplementation on intestinal adaptation.

MATERIALS/METHODS

Seven-week-old male Lewis rats underwent a 90% small bowel resection. The rats were randomly divided into two groups: group V (valine-rich diet) and group S (standard rat chow), according to the diet. The rats were sacrificed at the operation day and on postoperative days (POD) 7, 14, 30, and 60. The metrics were body weight (BW), blood amino acids, urine organic acids, and morphology of the residual small intestine.

RESULTS

The BW and the intestinal wet weight, jejunal crypt depth, and proliferating cell nuclear antigen-positive cells in group V at POD 7 were significantly higher than those values in group S, while those in group V at POD 30 and 60 were smaller than those in group S. The urine methylmalonic acid (MMA) level in group V at POD 30 and 60 was much higher than in group S.

CONCLUSION

Valine enhanced intestinal adaptation after massive small bowel resection in the acute phase. However, the long-term supplementation disturbed intestinal adaptation, which might be due to the high production of MMA.

Relationship Between Real-Time Monitoring of the Graft Motility and Mucosal Histology in Swine Intestinal Transplantation

We studied the correlation between the motility and the mucosal histology of the small bowel seeking to detect rejection in an early stage by real-time monitoring using a swine model. Intestinal transplantation (ITx) was performed orthotopically using FK506 immunosuppression. The distal about 20 cm segment of the allograft was exteriorized as a Thiry-Vella stoma for biopsies. Strain gauge (SG) force transducers were attached to the graft for real-time monitoring of graft motility. Pigs without ITx were used as controls (group 1). Rejection was classified into four groups by histologic findings: nonrejection (group 2), mild rejection (group 3), moderate rejection (group 4), and severe rejection (group 5). Migrating motor complex (MMC) phase III was analyzed for the following parameters: duration, amplitude, interval, motility index, velocity, and frequency of propagation. In group 2, all parameters were almost the same as those for group 1. In contrast, groups 4 and 5 showed most parameters significantly lower than those in group 1. In group 3, the contractility of the MMC was not significantly altered, but the frequency of the propagation was decreased significantly. In conclusion, graft motility detected by a real-time SG method correlated with the grade of mucosal histology. This method is useful to detect rejection at an early stage by examining the frequency of MMC propagation.

Endoscopic diverticulotomy for symptomatic pediatric esophageal diverticula

There have so far been few reports on esophageal diverticulum in children. We experienced two symptomatic pediatric cases with esophageal diverticulum. Our cases manifested high fever and dysphagia with chest pain during swallowing. The patients underwent endoscopic diverticulotomy. The septum between the diverticulum and the esophagus was cut using the argon plasma coagulation (APC 3000) system. We recommend an endoscopic diverticulotomy as an effective treatment modality for such symptomatic cases.

Immunosuppressive effect of nucleoside-nucleotide-free diet in rat allogeneic small intestinal transplantation

BACKGROUND

We evaluated the effects of nucleosides (NS) and nucleotides (NT) on the rejection of rat allogeneic small intestinal transplants.

METHODS

A 2-cm segment of jejunum from fetal Fischer rats (RT-1(lvl)) was transplanted at day 19 of gestation into the abdominal wall of 7-week-old Lewis rats (RT-1(l)) by a nonvascular technique. Two weeks before transplantation, recipient rats were separated into an NS-NT-free group and an NS-NT-supplemented group. At 2 days after transplantation, histologic study of the grafts was performed with hematoxylin-eosin staining and interleukin-2 (IL-2) production estimated in recipient blood using an ELISA method. The morphologic findings were graded in a blind fashion on a scale of 0 to 4, with 0 indicating an intact intestinal structure.

RESULTS

Mean plasma IL-2 levels of the NS-NT-free group were significantly lower than those of the NS-NT-supplemented group. The mean rejection score of the NS-NT-free group was also significantly lower than that of the NS-NT-supplemented group.

CONCLUSIONS

Administration of an NS-NT-free diet reduces acute rejection in rat small intestinal transplantations.

Comparison of nonmetal and metal hydrophilic photosensitizer, ATX-S10 (Na) and ATN-2, binding with human serum proteins using spectrophotometry

Intermolecular interactions of human serum proteins with a hydrophilic nonmetalloporphyrin, 13,17-bis(1-carboxypropionyl)carbomoylethyl-8-ethenyl-2-hydroxy-3-hydroxyiminoethylidene-2,7,12,18-tetramethylporphyrin sodium salt (ATX-S10 (Na)), or a hydrophilic gallium-metalloporphyrin, diethylenetriamine pentaacetic acid ester of 2-[1-(2-hydroxy-ethoxy)ethyl]-4-vinyl-deuteroporphyrin (IX) Ga complex (ATN-2), were investigated using spectrophotometry. ATX-S10 (Na) caused a bathochromic shift with albumin, high-density lipoprotein and low-density lipoprotein, but little or no shift was observed with hemopexin, transferrin and immunoglobulin G. In contrast, ATN-2 displayed a bathochromic shift only with hemopexin. These results suggest that the association energy of ATX-S10 (Na) with albumin might be slightly greater than that with lipoproteins and that of ATN-2 with hemopexin might be greater than that with other serum proteins.

Real-time monitoring for detecting rejection using strain gauge force transducers in porcine small bowel transplantation

PURPOSE

The clinical results of small bowel transplantation (SBT) have not been satisfactory mainly because of the immunological barrier. It is important to detect the presence of and to perform adequate treatment of rejection as early as possible to improve graft survival. Therefore, we have established a pig model to monitor graft motility as a means to detect rejection in real time.

METHODS

Orthotropic SBT was performed in 25 pigs using FK-506 (0.05 to 0.1 mg/kg/d) immunosuppression. The interdigestive motor patterns were evaluated using strain gauge force transducers (SG). Seven pigs without SBT were treated as controls (C). Animals that displayed migrating motor complex (MMC) activity as evidenced by duration, amplitude, and interval in the graft were alive more than 10 days with adequate oral feeding: the functional graft (FG) group. In contrast the rejection (R) group did not show these activities on data recorded within 10 days before death due to rejection.

RESULTS

The FG group showed MMC propagated throughout the graft with all parameters almost the same as the control group except for the duration. In contrast, all parameters in the group R were significantly lower than those in group FG, suggesting that group R motility was obviously impaired by rejection.

CONCLUSIONS

The SG method may afford real-time monitoring of transplanted bowel motility that could be useful to detect rejection after SBT.

Modulation of activator protein 1/DNA binding activity by acoustic overstimulation in the guinea-pig cochlea

Changes in gene expression are part of the homeostatic machinery with which cells respond to external stimuli or assaults. The activity of the early response transcriptional factor activator protein-1 (AP-1) can be modulated by a variety of environmental stimuli including those that alter the cellular oxidation/reduction status. This study investigates the activation of AP-1/DNA binding in the guinea-pig cochlea in response to acoustic overstimulation which produces reactive oxygen species. Electrophoretic mobility shift assays revealed that binding of AP-1 to its radiolabeled oligonucleotide probe markedly changed in nuclear extracts of inner ear tissues following intense noise exposure (4 kHz octave band, 115 dB, 5 h). AP-1/DNA binding increased in the organ of Corti and the lateral wall tissues immediately after the exposure, returning to near-baseline levels 5 h later. At 15 h after noise, a second peak of binding activity occurred in the organ of Corti whereas stria vascularis showed a lesser but more sustained activity. Binding in nuclear extracts from the spiral ganglion did not change. Incubation of nuclear extracts with antibodies against Fos/Jun family proteins prior to a supershift assay showed Fra-2 as a major component of the AP-1 complex immediately after the noise exposure. In the organ of Corti, Fra-2 immunoreactivity was localized to the middle turn, i.e. the region which is most affected by the 4-kHz octave band exposure. The results suggest the modulation of gene expression via the activation of AP-1 as a consequence of noise trauma but also demonstrate differential responses in cochlear tissues.

Effects of omega-3 fatty acids in rat allogenic small intestinal transplantation

The aim of this study was to estimate the effect of omega-3 fatty acids on the recipient and graft immune response after rat allogenic small intestinal transplantation. Seven-week-old Lewis rats were randomly assigned to one of three groups according to the diet received: an FO group (fish oil supplemented), an SB group (soy bean oil supplemented) or a control group (normal rat chow). The recipient Lewis rats were each given their respective group diet for 12 days, and then, on the 19th day of gestation, a 2 cm jejunum from the donor fetal Fischer rat was transplanted into the abdominal wall of the recipient rats using a non-vascular anastomotic technique. The recipient rats were killed on day 2 after transplantation, and the recipient plasma IL-2, IFN-gamma and IL-1 beta levels were determined. In addition, the histological findings of the graft were analyzed. The cytokine levels of the FO group were significantly lower than the other two groups. In order to determine the grade of rejection, the morphological findings were blindly graded on a scale of 0-4. The mean grade of the FO group was also significantly lower than the other two groups. Omega-3 fatty acids are therefore considered to have an immunosuppressive effect on rat allogenic small intestinal transplantation based on the recipient plasma IL-1 beta, TNF and IL-2 levels and the histological findings of the grafts.

Molecular regulation of the oxytocin receptor in peripheral organs

The oxytocin receptor belongs to the G-protein-coupled seven transmembrane receptor superfamily. Its main physiological role is regulating the contraction of uterine smooth muscle at parturition and the ejection of milk from the lactating breast. Oxytocin receptor expression is observed not only in the myometrium and mammary gland but also in the endometrium, decidua, ovary, testis, epididymis, vas deferens, thymus, heart and kidney, as well as in the brain. The expression profile shows a tissue-specific as well as a stage-specific pattern. The oxytocin receptor gene is a single-copy gene consisting of four exons and three introns, localized at 3p25-3p26.2 in the human chromosome. In transfection studies using a fusion construct containing the promoter region of the oxytocin receptor gene inserted in a reporter plasmid, neither proinflammatory cytokines nor oestrogen directly activate the gene. The nuclear fractions from up-regulated (term myometrium) and down-regulated (non-pregnant myometrium) tIssues show differential patterns of protein binding to the 5'-flanking region, and a human homologue of chicken MafF has been cloned as a term-myometrium-specific oxytocin receptor modulator. The oxytocin receptor gene appears to be highly methylated. Methylation around intron 1 and in intron 3 might contribute to tIssue-specific suppression of the gene. The oxytocin receptor is also regulated by desensitization, whose mechanism appears to involve loss of ligand-binding activity of the protein as well as suppression of the oxytocin receptor mRNA transcription. These findings taken together indicate that the oxytocin receptor is regulated in a very complicated manner, and the transcriptional regulatory elements critical for this regulation should be investigated further.

DNA methylation of the human oxytocin receptor gene promoter regulates tissue-specific gene suppression

In the human oxytocin receptor (OTR) gene, there is a CpG island from 140 bp upstream to 2338 bp downstream of the transcription start site (TSS). We investigated whether the methylation state of this region affects the transcription of the OTR gene. HepG2 derived from human hepatoblastoma, in which OTR gene transcription was suppressed, was treated with a demethylating agent, 5-azacytidine (Aza-C) for 2 days. Semiquantitative RT-PCR indicated that OTR mRNA was significantly increased by Aza-C treatment in a dose-dependent manner. We estimated the level of methylation within the CpG islands of the OTR gene in peripheral blood leukocytes, nonpregnant uterine myometrium, term uterine myometrium and liver. A 1.5-kb region located 5' upstream of the translation start site was divided into four fragments. Each was amplified by PCR after complete digestion with methylation-sensitive restriction enzyme HpaII. The amount of PCR products was largest in the liver, suggesting that this CpG island in the OTR gene is most highly methylated in liver, where the gene is always inactivated. We compared the effect of in vivo methylation of the CpG island on transcriptional activity of an OTR-reporter plasmid. The reporter gene activity of expression plasmid -2860/+1342-GL3, containing the CpG island, in HepG2 cells was suppressed to 30.6% of the control level after methylation with SssI methylase, while that of -2840/+144-GL3, without the CpG island was suppressed only to 81.4%. The deletion of the segment (MT2) where the level of methylation was most different between liver and uterus (-2860/+1342(del)MT2-GL3) rescued the suppression rate to 68.0%. These results indicate that the methylation of the CpG island in the human OTR gene promoter suppressed its transcription at least in liver and may regulate tissue specific gene expression among organs.

Relationship between plasma insulin concentration and plasma remnant lipoprotein response to an oral fat load in patients with type 2 diabetes

OBJECTIVES

The goal of this study was to evaluate the relative effects of hyperglycemia and hyperinsulinemia on postprandial remnant lipoprotein (RLP) concentrations in newly diagnosed type 2 diabetics.

BACKGROUND

Increases in fasting RLP concentration have been described in type 2 diabetics, as well as in insulin-resistant nondiabetics. Given the atherogenicity of RLPs, we have extended these observations by assessing postprandial RLP concentrations and observing that hyperglycemia was necessary for the increase in RLP concentrations.

METHODS

Patients with type 2 diabetes were subdivided on the basis of their plasma insulin response to oral glucose into hyperinsulinemic (H-DM) and normoinsulinemic (N-DM) groups of 15 patients each. Plasma triglyceride (TG), RLP-TG and RLP cholesterol (RLP-C) concentrations were determined before and 2 and 4 h after an oral fat load in these patients and 10 control (CTL) subjects.

RESULTS

Plasma TG, RLP-TG and RLP-C concentrations peaked 2 h after the fat load in the CTL group, returning to baseline within 4 h. In contrast, concentrations of these variables increased throughout the 4-h study in both groups of patients with type 2 diabetes. Total integrated plasma RLP-TG and RLP-C responses above baseline after the oral fat load were significantly higher in the H-DM group compared with the CTL (p = 0.019 and 0.009, respectively) or N-DM (p = 0.026 and 0.029, respectively) groups. Post-heparin lipoprotein lipase activities and apo E phenotypes were similar in the H-DM and N-DM groups.

CONCLUSIONS

Remnant lipoprotein response to an oral fat load is significantly increased in hyperinsulinemic patients with type 2 diabetes. These changes may increase the risk of coronary heart disease in these individuals.

Triglyceride-rich lipoprotein cholesterol exceeds low-density lipoprotein cholesterol in hypertriglyceridemia patients

The atherogenicity of triglyceride-rich lipoprotein has been revealed. This study was performed to explore the clinical importance of triglyceride-rich lipoprotein by measuring its cholesterol content and comparing it with other lipoprotein fractions. Blood samples were obtained from 103 patients whose fasting plasma triglyceride concentration exceeded 300 mg/dl. The cholesterol monitor using the technique of high-performance liquid chromatography was used for the measurement of their plasma cholesterol concentrations and the determination of cholesterol distribution among lipoprotein fractions. This monitor showed 4 peaks: large-triglyceride-rich lipoprotein, small-triglyceride-rich lipoprotein, low-density lipoprotein, and high-density lipoprotein. Total cholesterol increased with increasing triglyceride. The increment of total cholesterol was nearly equal to that of small-triglyceride-rich lipoprotein cholesterol. Small-triglyceride-rich lipoprotein cholesterol exceeded low-density lipoprotein cholesterol where plasma triglyceride concentration was over 500 mg/dl. In conclusion, triglyceride-rich lipoprotein may be clinically important for hypertriglyceridemic patients as a source of cholesteryl ester in arteriosclerotic plaques, and increased triglyceride-rich lipoprotein cholesterol may be used as a basis for hypertriglyceridemia atherogenicity. Our study suggests that hypertriglyceridemia should be treated to prevent arteriosclerotic disease.

Decrease in level of APG-2, a member of the heat shock protein 110 family, in murine brain following systemic administration of kainic acid

APG-2 belongs to the heat shock protein 110 family. Although kainic acid (KA)-induced seizures are known to elicit expression of inducible heat shock protein 70 (HSP70) in the brain, no investigation has been carried out on the APG-2 level after excitatory amino acid-induced seizures. By means of an immunoblot assay, we determined the levels of HSP70 and APG-2 in discrete brain structures of mice after a single intraperitoneal injection of KA or N-methyl-D-aspartic acid (NMDA). APG-2 level was significantly decreased in frontal cortex, hippocampus, and striatum three days after the administration of KA, while HSP70 level was increased in these regions following the administration. In any of these regions, APG-2 levels were returned to the control levels 10 days after the administration. However, no significant changes were observed in levels of both HSP70 and APG-2 in hypothalamus, midbrain, medulla-pons, and cerebellum of the mice. By contrast, NMDA administration did not significantly affect both levels in any of the regions examined. These findings indicate that the transient decrease in APG-2 expression is one of the intracellular events elicited by signals peculiar to KA, but not by those peculiar to NMDA, in telencephalon of murine brain.

Differential in vitro degradation of particular Fos family members expressed by kainic acid in nuclear and cytosolic fractions of murine hippocampus

Mice were injected with kainic acid (KA) at a convulsive dose, followed by homogenization of the hippocampus in the presence of different protease and phosphatase inhibitors, and subsequent preparation of nuclear and cytosolic fractions. An intraperitoneal injection of KA resulted in marked expression of particular Fos family members, including c-Fos, Fra-2, and Fos-B, but not Fra-1 proteins, in both fractions 2 to 18 h after administration. These fractions were individually incubated at 30 degrees C for 1 to 18 h for determination of in vitro degradation. Similarly rapid degradation was seen with c-Fos protein between nuclear fractions obtained 2 and 18 h after administration, while no significant degradation was found for c-Fos protein in cytosolic fractions obtained 2 h after administration during incubation. By contrast, in vitro incubation led to rapid degradation of c-Fos protein in cytosolic fractions obtained 18 h after administration. Degradation profiles were peculiar to each member protein in nuclear and cytosolic fractions obtained 2 and 18 h after administration. Dialysis prevented degradation of c-Fos protein in nuclear fractions without markedly affecting that in cytosolic fractions in a manner independent of the time after administration. The addition of inhibitors for phosphatases, but not for proteases, accelerated the degradation of c-Fos protein in nuclear fractions previously dialyzed. These results suggest that in vivo KA signals may modulate heterologous machineries responsible for breakdown of each Fos family member in a unique manner in nuclear fractions, rather than cytosolic fractions, of murine hippocampus.

Inhibition of vesicular glutamate storage and exocytotic release by Rose Bengal

It had been thought that quantal size in synaptic transmission is invariable. Evidence has been emerging, however, that quantal size can be varied under certain conditions. We present evidence that alteration in vesicular [(3)H]L-glutamate (Glu) content within the synaptosome (a pinched-off nerve ending preparation) leads to a change in the amount of exocytotically released [(3)H]Glu. We found that Rose Bengal, a polyhalogenated fluorescein derivative, is a quite potent membrane-permeant inhibitor (K(i) = 19 nM) of glutamate uptake into isolated synaptic vesicles. This vesicular Glu uptake inhibition was achieved largely without affecting H(+)-pump ATPase. We show that various degrees of reduction elicited by Rose Bengal in [(3)H]Glu in synaptic vesicles inside the synaptosome result in a corresponding decrease in the amount of [(3)H]Glu released in a depolarization- (induced by 4-aminopyridine) and Ca(2+)-dependent manner. In contrast, fluorescein, the halogen-free analog of Rose Bengal, which is devoid of inhibitory activity on vesicular [(3)H]Glu uptake, failed to change the amount of exocytotically released [(3)H]Glu. These observations suggest that glutamate synaptic transmission could be altered by pharmacological intervention of glutamate uptake into synaptic vesicles in the nerve terminal, a new mode of synaptic manipulation for glutamate transmission.

Effects of glutathione depletion by 2-cyclohexen-1-one on excitatory amino acids-induced enhancement of activator protein-1 DNA binding in murine hippocampus

We have investigated the role of glutathione in mechanisms associated with excitatory amino acid signaling to the nuclear transcription factor activator protein-1 (AP1) in the brain using mice depleted of endogenous glutathione by prior treatment with 2-cyclohexen-1-one (CHX). In the hippocampus of animals treated with CHX 2 h before, a significant increase was seen in enhancement of AP1 DNA binding when determined 2 h after the injection of kainic acid (KA) at low doses. The sensitization to KA was not seen in animals injected with CHX 24 h before, in coincidence with the recovery of glutathione contents to the normal levels. By contrast, CHX did not significantly affect the potentiation by NMDA of AP1 binding under any experimental conditions. Prior treatment with CHX resulted in facilitation of behavioral changes induced by KA without affecting those induced by NMDA. These results suggest that endogenous glutathione may be at least in part involved in molecular mechanisms underlying transcriptional control by KA, but not by NMDA, signals of cellular functions.

Outcome of fetal cystic hygroma and experience of intrauterine treatment

OBJECTIVE

To review our cases of fetal cystic hygroma and to examine the prognostic factors with the goal of establishing criteria for the intrauterine treatment for cystic hygroma.

PATIENTS AND METHODS

Thirty-one cases of fetal cystic hygroma were managed by us from January 1988 to December 1997, and 21 cases were available for analysis. Three prognostic factors, namely chromosomal abnormality, structural anomaly and hydrops fetalis, were evaluated. We treated 2 cases of cystic hygroma associated with hydrops fetalis in utero using OK-432 injection under ultrasound guidance.

RESULTS

The fetuses without any of the prognostic factors listed above showed a good prognosis throughout the fetal and neonatal periods. However, in this group, 2 infants with large tumors died of hemorrhage from the tumor at 6 months and 3 years of age, respectively. Cases with hydrops fetalis without chromosomal abnormalities or structural anomalies (5 cases) resulted in either intrauterine fetal death (IUFD, 2 cases) or early perinatal neonatal death (early PND, 3 cases). The cause of early PND was circulatory failure. Most of the hydrops cases with either a chromosomal abnormality or structural anomaly resulted in IUFD before 22 weeks of gestation. The size of the cyst decreased in 1 of 2 cases treated in utero.

CONCLUSIONS

The fetal cases of cystic hygroma showing hydrops fetalis without chromosomal abnormalities or structural anomalies are considered to be possible candidates for intrauterine therapy. Those with very large cystic hygroma without any of the three prognostic factors are also thought to be candidates for fetal treatment. Based on our clinical experience, sclerotherapy using OK-432 is considered to be a treatment option in selected cases with fetal cystic hygroma.

Characterization with [3H]quisqualate of group I metabotropic glutamate receptor subtype in rat central and peripheral excitable tissues

Radioligand binding studies were performed to label metabotropic glutamate receptor (mGluR) in rat brain synaptic membranes using [3H]quisqualic acid (QA) synthesized in our laboratory as a radioligand. In the presence of ionotropic glutamate receptor (iGluR) agonists, including N-methyl-D-aspartic (NMDA), DL-alpha-amino-3-hydroxy-5-methylisoxasole-4-propionic (AMPA) and kainic acids (KA), at concentrations maximally effective in displacing each receptor binding, the agonists for group I mGluR subtype (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (trans-ACPD) and (S)-3,5-dihydroxyphenylglycine ((S)-3,5-DHPG) more potently displaced [3H]QA binding in a concentration-dependent manner than their absence. The addition of these three iGluR agonists did not significantly affect potencies of (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) and L-(+)-2-amino-4-phosphonobutyric acid (L-AP4) to displace [3H]QA binding. Scatchard analysis revealed that [3H]QA binding consisted of a single component with a maximal number of binding sites (B(max)) of 431.6 fmol/mg protein and a dissociation constant (K(d)) of 50.9 nM, in the presence of the three iGluR agonists. [3H]QA binding was markedly inhibited by GTP and its analogues; but not by GDP, GMP and ATP, under these conditions. Inhibition by GTP was seen in all central structures examined, but [3H]QA binding was not detectable in peripheral tissues, such as pituitary and adrenal glands. Neither reverses transcription polymerase chain reaction nor immunoblotting analysis demonstrated the expression of mGluR1 and mGluR5 subunits in the aforementioned two peripheral tissues. These results suggest that [3H]QA indeed labels group I mGluR subtype functionally coupled to GTP binding protein in rat brain synaptic membranes under the experimental conditions employed. Group I mGluR subtype seems to be selectively distributed in central structures but not in pituitary and adrenal glands.

Manganese intoxication during intermittent parenteral nutrition: report of two cases

BACKGROUND AND METHODS

The administration of trace elements is thought to be needed in patients receiving long-term parenteral nutrition. Recently, manganese intoxication or deposition was documented in such patients. We report two cases of manganese intoxication during intermittent parenteral nutrition including manganese. Manganese had been administered for 4 years at a frequency of one or two times per week in one case and for 5 years at a frequency of one or two times per month in the other case. Both cases showed mild symptoms with headache and dizziness. One case had mild hepatic dysfunction and the other did not. The whole-blood manganese level increased in one case, but not in the other case. T1-weighted magnetic resonance images revealed symmetrical high-intensity areas in basal ganglia and thalamus in both cases. After the administration of manganese was stopped, these symptoms all disappeared and the magnetic resonance images abnormalities gradually improved in both patients. Mild long-term manganese intoxication is thus considered to occur regardless of the frequency of using a manganese supplement.

CONCLUSIONS

Patients should be carefully monitored when receiving long-term parenteral nutrition including manganese, even when the manganese dose is small and the frequency of receiving a manganese supplement is low.

Differential expression and phosphorylation of particular fos family members by kainate in nuclear and cytosolic fractions of murine hippocampus

An i.p. injection of kainate resulted in severe losses of neuronal cells stained by Cresyl Violet in the CA1 and CA3 pyramidal layers of the murine hippocampus within two weeks, without affecting those in the dentate granule layer up to six weeks. Immunohistochemical analysis revealed marked and predominant expression of Fos family members, including c-Fos, Fos-B and Fra-2 proteins, in the dentate granule layer of the hippocampus, but not in the pyramidal layers, 2-18h after administration. Immunoblotting experiments showed that kainate induced more potent expression of c-Fos protein in nuclear fractions obtained 2h after injection than those obtained 18h later, with similar expression between cytosolic fractions obtained 2 and 18h after administration. Both Fos-B and Fra-2 proteins were more potently expressed in nuclear and cytosolic fractions 18h after administration than 2h when determined on immunoblotting analysis. Two-dimensional electrophoresis revealed expression of several proteins immunoreactive to the anti-c-Fos antibody with different isoelectric points in response to kainate in nuclear and cytosolic fractions of the hippocampus for 2-18h after a single injection. Immunoprecipitation analysis using the anti-c-Fos antibody showed phosphorylation of c-Fos protein on serine residues in hippocampal nuclear fractions 2h after administration, with additional phosphorylation on tyrosine residues 18h later. Prior treatment of the protein synthesis inhibitor cycloheximide prevented the expression of immunoreactivities to the anti-c-Fos antibody detected on two-dimensional electrophoresis in hippocampal nuclear fractions obtained 2h after administration.These results suggest that in vivo kainate signals may lead to persistent expression of the transcription factor activator protein-1 that consists of different Fos family members, as well as of c-Fos protein phosphorylated on serine and/or tyrosine residues, at an early stage after administration. Such signal consolidation processes could play a role in mechanisms associated with neuronal survival after kainate in the dentate granular layer of murine hippocampus.

Direct radiolabeling by [3H]quisqualic acid of group I metabotropic glutamate receptor in rat brain synaptic membranes

[3H]Quisqualic acid (QA) was synthesized and used to label metabotropic glutamate receptor (mGluR) in rat brain synaptic membranes in the presence of three different ionotropic glutamate receptor agonists at respective saturating concentrations. Of several mGluR agonists tested, group I agonists were more potent in displacing [3H]QA binding than group II and group III agonists in the presence of the three ionotropic agonists. [3H]QA binding was markedly inhibited by guanine nucleotide analogues in a concentration-dependent manner at a concentration range of 10 nM to 1 mM. Scatchard analysis revealed that [3H]QA binding consisted of a single component with a K(d) of 50.9+/-5.3 nM and a B(max) of 431. 6+/-18.3 fmol/mg protein. These results suggest that [3H]QA indeed labels group I mGluR functionally coupled to GTP binding protein in rat brain synaptic membranes when determined under the experimental conditions employed.

Relationship between hyperinsulinemia and remnant lipoprotein concentrations in patients with impaired glucose tolerance

This study was performed to explore further the association between insulin resistance and plasma remnant lipoprotein (RLP) concentration. For this purpose we used the sum of the plasma insulin concentrations before and 30, 60, 90, 120, and 180 min after a 75-g oral glucose load (sigmaIRI) as a surrogate measure of insulin resistance in 61 subjects with impaired glucose tolerance. SigmaIRI was determined on 2 occasions, before and 16 weeks after initiation of a diet and exercise program. At baseline, sigmaIRI correlated with the sum of the plasma glucose concentrations in response to the 75-g oral glucose load (r = 0.26; P < 0.04) as well as plasma concentrations of triglyceride (r = 0.21; P = 0.09), RLP-cholesterol (r = 0.41; P < 0.001), and RLP-triglyceride (r = 0.46; P < 0.001). In contrast, neither total (r = 0.07) nor high density lipoprotein (HDL) cholesterol (r = 0.04) concentrations correlated with sigmaIRI. SigmaIRI was lower in 42 subjects following life-style intervention, associated with significant (P < 0.005) reductions in sigmaglucose, and fasting glucose, insulin, triglyceride, RLP-cholesterol, and RLP-triglyceride concentrations. However, none of these variables decreased in the 19 subjects whose sigmaIRI did not fall. Finally, the change in sigmaIRI following intervention with diet and exercise was significantly associated with differences in sigmaglucose (r = 0.63; P < 0.001) and fasting glucose (r = 0.26; P < 0.05), insulin (r = 0.79; P < 0.001), triglyceride (r = 0.29; P < 0.03), RLP-cholesterol (r = 0.71; P < 0.001), and RLP-triglyceride (r = 0.49; P < 0.001) concentrations. These results demonstrate that variations in concentrations of RLPs are highly correlated with changes in sigmaIRI, consistent with the possibilities that 1) RLP measurements are useful estimates of insulin resistance; and 2) an increase in RLP concentrations may provide the mechanistic link between insulin resistance and coronary heart disease.

Stress responses in graft and native intestine after rat heterotopic small bowel transplantation

BACKGROUND

Cardiac transplantation has been shown to induce heat shock protein expression, and reactivity to these stress proteins has been implicated in acute and chronic allograft rejection. This study assessed Hsp60 and Hsp70 expression in graft and native small intestine after rat small bowel transplantation.

METHODS

Heterotopic small bowel transplantation was performed between PVG donor and DA recipient rats, a subgroup of which received tacrolimus immunosuppression (1 mg x kg(-1) x day(-1)). Untransplanted and isografted (PVG-->PVG) animals served as controls. Paraffin sections of graft and native intestine on day 5 after transplantation were stained by immunohistochemistry, and heat shock protein expression was graded blindly by three observers.

RESULTS

Villus epithelial cell expression of Hsp60, but not Hsp70, was increased in allografts. The induction of Hsp60 in the villus epithelium was not controlled by tacrolimus. Hsp60 and Hsp70 expression was induced in the lamina propria of isografts and allografts. This response was more pronounced in allografts and was significantly reduced, but not totally abrogated, by tacrolimus. Interestingly, heat shock protein expression was also induced in the native intestine lamina propria and epithelium of allograft recipients, suggesting the induction of stress responses at sites other than the transplanted organ.

CONCLUSIONS

Small bowel transplantation induces a stress response in both the graft and native intestine. The early and prolonged expression of these proteins may influence the induction of anti-heat shock protein reactivity and have an adverse effect on graft outcome after small bowel transplantation.

Acoustic trauma enhances DNA binding of transcription factor AP-1 in the guinea pig inner ear

Radiolabeled probes for the transcription factor, activator protein-1 (AP-1), bound differentially to nuclear fractions of discrete structures of the guinea pig cochlea (organ of Corti, lateral wall tissues, and spiral ganglion). Noise exposure (4 kHz octave band, 115 dB, for 5 h) significantly increased AP-1 binding in both the organ of Corti and lateral wall tissues but not in the spiral ganglion. Supershift analysis using an antibody against c-Fos protein demonstrated that enhancement of AP-1/DNA binding was at least in part due to the expression of c-Fos protein. These results suggest that AP-1 is involved in the molecular mechanism(s) mediating noise-induced cochlear damage.

High incidence of respiratory distress syndrome (RDS) in infants born to mothers with placenta previa

OBJECTIVE

To evaluate the incidence of respiratory distress syndrome (RDS) in infants born to mothers with placenta previa and to assess the risk factors for RDS.

METHODS

Ninety-nine pregnant women with placenta previa who delivered by cesarean section at 30-35 weeks of gestation were compared retrospectively with 102 pregnant women matched for week of gestation and birth year, who underwent elective cesarean section. Maternal characteristics, neonatal outcome, and incidence of RDS were analyzed. Umbilical cord blood samples were collected at delivery and were used to determine cortisol, epinephrine, and norepinephrine levels. Student's t-test, the chi-square test, and Fisher's exact test were used for statistical comparisons. P < 0.05 was considered significant. The Mann-Whitney U test was used for comparison of continuous variables.

RESULTS

Preeclampsia, histological chorioamnionitis, and premature rupture of membranes were significantly lower in the placenta previa group (placenta previa: 2.0% vs. control: 14.7%, P < 0.01; 14.1% vs. 30.1%, P < 0.01; 7.1% vs. 17.6%, P < 0.05, respectively). The incidence of RDS was significantly higher in the placenta previa group than in the control group (29.3% vs. 6.9%, P < 0.0001). The cortisol level in umbilical cord blood in the placenta previa group was lower than in the control group (median 7.3, range 4.4-14.9 microg/dl vs. median 10.6, range 4.9-30.3 microg/dl, P < 0.05). There were no significant differences in epinephrine or norepinephrine levels between the two groups.

CONCLUSIONS

The incidence of RDS in infants delivered at 30-35 weeks' gestation by cesarean section was significantly higher in mothers with placenta previa than in women without placenta previa. This may reflect decreased fetal stress since the cord blood cortisol levels were found to be lower in women with placenta previa.

Expression of APG-2 protein, a member of the heat shock protein 110 family, in developing rat brain

APG-2 protein is a member of the heat shock protein 110 family, and it is thought to play an important role in the maintenance of neuronal functions under physiological and stress conditions. However, neither the tissue-distribution of APG-2 protein nor developmental change of its expression has been studied at the protein level. Therefore, we generated an antiserum against APG-2 protein and studied expression of this protein in rat brain and other tissues by use of the Western blot method. The results showed a high expression of APG-2 protein in various regions of the central nervous system (cerebral cortex, hippocampus, striatum, midbrain, hypothalamus, cerebellum, medulla pons, and spinal cord) throughout the entire postnatal stage. Similarly, a high level of APG-2 protein was detected in the whole brain of rat embryos and in adult rat tissues such as liver, lung, spleen, and kidney. In contrast, its expression in heart was high at postnatal days 1 and 3, but thereafter drastically decreased to a low level. Furthermore, APG-2 protein was detected in neuronal primary cultures prepared from rat cerebral cortex, and its level did not change notably during neuronal differentiation. These results show that APG-2 protein is constitutively expressed in various tissues and also in neuronal cells throughout the entire embryonic and postnatal period. suggesting that it might play an important role in these tissues under non-stress conditions.

High-level expression of the Mnb/Dyrk1A gene in brain and heart during rat early development

We previously isolated human MNB/DYRK1A cDNA from "the Down syndrome critical region" of human chromosome 21 (Shindoh et al., 1996, Biochem. Biophys. Res. Commun. 225: 92-99). As described herein, we prepared a polyclonal anti-MNB/DYRK1A antibody and used it in a Western blot assay to assess the expression of the MNB/DYRK1A protein during rat development. The MNB/DYRK1A protein was expressed strongly not only in the brain but also in other tissues from embryonic rats. At the early postnatal stage, expression of the protein was high in the central nervous system and heart, but low in liver, lung, spleen, and kidney. The level of MNB/DYRK1A protein in all tissues studied gradually decreased with postnatal growth. Similarly, Northern blot analysis revealed that a major 6.0-kb transcript of the Mnb/Dyrk1A gene was expressed at a high level in the brain during the early postnatal period but that its level was low in the adult. The finding that the MNB/DYRK1A protein is expressed strongly in the central nervous system and heart may indicate a significant role for this protein in the development of these organs.

Sustained potentiation of AP1 DNA binding is not always associated with neuronal death following systemic administration of kainic acid in murine hippocampus

Mice were intraperitoneally injected with kainic acid (KA), followed by dissection of frozen coronal sections and subsequent punching out of the pyramidal and granular cell layers in the hippocampus under a binocular microscope. Systemic administration of KA resulted in marked and sustained potentiation of binding of a radiolabeled double stranded oligonucleotide probe for the nuclear transcription factor activator protein-1 (AP1) in the pyramidal cell layers of the CA1 and CA3 subfields and the granule cell layers of the dentate gyrus 2-18 h later. Morphological evaluation using cresyl violet revealed marked losses of neuronal layers in the pyramidal CA1 and CA3 subfields, but not in the granular dentate gyrus, within 6 weeks after administration. Supershift analysis using antibodies against different Jun and Fos family members differentiated between AP1 DNA binding in hippocampal nuclear extracts obtained 2 and 18 h after the administration of KA. These results suggest that neuronal death may not always follow modulation of de novo synthesis of particular proteins through sustained potentiation of AP1 DNA binding which involves expression of different Jun and Fos family members in response to systemic administration of KA in murine hippocampus.

Fetal stabilization for antenatally diagnosed diaphragmatic hernia

BACKGROUND/PURPOSE

Infants with congenital diaphragmatic hernia have pulmonary hypoplasia resulting in persistent pulmonary hypertension of neonates (PPHN), which is the main contributor to both high mortality and morbidity. The pulmonary artery bed in patients with congenital diaphragmatic hernia (CDH) is underdeveloped and is very sensitive to slight stimuli. It is, therefore, vital to avoid any factors that might increase pulmonary vascular resistance during the perinatal treatment of these patients. Recently, fetal anesthesia for perinatal stabilization in patients with CDH has been reported. However, the efficacy of this method remains controversial. The aim of this study is to analyze the benefits of fetal stabilization using fetal anesthesia in patients with CDH.

METHODS

The authors have seen 9 cases of antenatally diagnosed CDH and attempted fetal stabilization. The indication for fetal stabilization was a lung thoracic ratio of less than 0.2, without any severe associated anomalies. The protocol for fetal stabilization was (1) monitoring the fetal respiratory movement and heart beat by ultrasonography, (2) the administration of morphine (20 to 30 mg) and diazepam (5 mg) to the mother, (3) the confirmation of any interruptions in fetal movement followed by a cesarean section, (4) pancuronimum (0.5 mg) was given through the umbilical vessels, (5) intubation before clamping of the umbilical cord, and (6) high-frequency oscillatory ventilation (HFO) without bagging.

RESULTS

The lung-thratic ratio (LTR) was between 0.06 to 0.17 (average, 0.10+/-0.04). Operation was performed in 7 of 9 patients at between 2.5 and 27 hours after birth. The overall survival rate was 66.7% (6 of 9). All of the patients who underwent operation within 5 hours after birth survived.

CONCLUSIONS

Perinatal stabilization using fetal anesthesia was found to be effective in preventing PPHN and shortening the period of preoperative stabilization. It also improved the survival rate of patients with severe CDH.

Molecular cloning of a human MafF homologue, which specifically binds to the oxytocin receptor gene in term myometrium

The US-2 DNA-binding element (ggaatgattactcagctaga) in the promoter of the human oxytocin receptor (OTR) gene has been shown to bind specifically nuclear proteins from human myometrium at parturition. To elucidate the molecular mechanisms involved in OTR gene upregulation at term, the US-2 element was used in a yeast one-hybrid system to screen a cDNA library derived from term human myometrium. Positive clones were further screened by electrophoretic mobility shift assay for their ability to bind the human OTR gene promoter, containing the US-2 motif. A 2.3-kb full-length cDNA encoding a human homologue of chicken MafF (hMafF) was isolated. hMafF represents an 18-kDa protein and contains an extended leucine zipper structure, but lacks a transactivation domain. Furthermore, Northern hybridization showed strong hMafF mRNA expression in the kidney and in term myometrium only, but not in nonpregnant myometrium. The hMafF protein is also preferentially expressed in term myometrium, as shown by specific binding to the OTR promoter. The highly specific binding of hMafF to the US-2 motif in the human OTR gene, together with its pattern of expression, supports a role for hMafF in OTR gene upregulation at term.

Glutathione and signal transduction in the mammalian CNS

The tripeptide glutathione (GSH) has been thoroughly investigated in relation to its role as antioxidant and free radical scavenger. In recent years, novel actions of GSH in the nervous system have also been described, suggesting that GSH may serve additionally both as a neuromodulator and as a neurotransmitter. In the present article, we describe our studies to explore further a potential role of GSH as neuromodulator/neurotransmitter. These studies have used a combination of methods, including radioligand binding, synaptic release and uptake assays, and electrophysiological recording. We report here the characteristics of GSH binding sites, the interrelationship of GSH with the NMDA receptor, and the effects of GSH on neural activity. Our results demonstrate that GSH binds via its gamma-glutamyl moiety to ionotropic glutamate receptors. At micromolar concentrations GSH displaces excitatory agonists, acting to halt their physiological actions on target neurons. At millimolar concentrations, GSH, acting through its free cysteinyl thiol group, modulates the redox site of NMDA receptors. As such modulation has been shown to increase NMDA receptor channel currents, this action may play a significant role in normal and abnormal synaptic activity. In addition, GSH in the nanomolar to micromolar range binds to at least two populations of binding sites that appear to be distinct from all known excitatory amino acid receptor subtypes. GSH bound to these sites is not displaceable by glutamatergic agonists or antagonists. These binding sites, which we believe to be distinct receptor populations, appear to recognize the cysteinyl moiety of the GSH molecule. Like NMDA receptors, the GSH binding sites possess a coagonist site(s) for allosteric modulation. Furthermore, they appear to be linked to sodium ionophores, an interpretation supported by field potential recordings in rat cerebral cortex that reveal a dose-dependent depolarization to applied GSH that is blocked by the absence of sodium but not by lowering calcium or by NMDA or (S)-2-amino-3-hydroxy-5-methyl-4-isoxazolepropionate antagonists. The present data support a reevaluation of the role of GSH in the nervous system in which GSH may be involved both directly and indirectly in synaptic transmission. A full accounting of the actions of GSH may lead to more comprehensive understanding of synaptic function in normal and disease states.

Predominant expression of nuclear activator protein-1 complex with DNA binding activity following systemic administration of N-methyl-D-aspartate in dentate granule cells of murine hippocampus

The systemic administration of N-methyl-D-aspartate (100 mg/kg, i.p.) resulted in preferential but transient expression of the transcription factor activator protein-1 in the granule cell layers of the dentate gyrus in the murine hippocampus by maximally 700% 1 h later, without markedly affecting that in the pyramidal cell layers of the CA1 and CA3 subfields for 4 h. The potentiation was completely prevented by prior administration of the N-methyl-D-aspartate channel blocker dizocilpine at 10 mglkg. By contrast, kainate (40 mg/kg, i.p.) potentiated activator protein-1 DNA binding in adjacent areas around the pyramidal and granule cell layers, in addition to potentiating that in neuronal cell layers of the CA1 and CA3 subfields and the dentate gyrus. Light microscopic analysis revealed that kainate, but not N-methyl-D-aspartate, induced marked losses of the pyramidal cells in the CAI and CA3 subfields, without affecting the dentate granule cells, for 14 days after administration. Limited proteolysis by V8 protease and supershift, as well as immunoblotting assays using antibodies against c-Fos and c-Jun, invariably gave support for differential expression by N-methyl-D-aspartate and kainate of the activator protein-1 complex consisting of different partner proteins. Moreover, two-dimensional electrophoresis followed by immunoblotting analysis revealed the expression of several nuclear proteins immunoreactive with the anti-c-Fos antibody at molecular weights and isoelectric points clearly different from those of c-Fos itself in response to kainate, but not N-methyl-D-aspartate, in the hippocampus. These results suggest that in vivo N-methyl-D-aspartate signals are predominantly transduced into cell nuclei to express activator protein-1 complex through molecular mechanisms different from those for kainate signals in the granule cells of the dentate gyrus in the murine hippocampus.

Constitutive expression of cytoplasmic activator protein-1 with DNA binding activity and responsiveness to ionotropic glutamate signals in the murine hippocampus

Gel retardation electrophoresis revealed that cytosolic fractions contained DNA binding activity of the transcription factor activator protein-1 with profiles different from those reported in nuclear extracts in murine brain. In particular, activator protein-1 DNA binding was almost undetectable at 25 degrees C in the presence of both KCl and MgCl2 in cytosol fractions. Moreover, cytoplasmic activator protein-1 binding occurred at three different mobilities on the gel when determined at 2 degrees C in the absence of MgCl2. Systemic administration of N-methyl-D-aspartate and kainate led to marked potentiation of cytoplasmic activator protein-1 binding detected as slow bands in the murine hippocampus, without markedly affecting that as a fast band. Immunoblotting and supershift assays revealed much higher expression of both immunoreactive c-Jun and c-Fos in hippocampal cytosolic fractions in response to the administration of kainate than N-methyl-D-aspartate. These results suggest that activator protein-1 may be constitutively expressed in the cytoplasm with DNA binding activity and responsiveness to ionotropic glutamate signals in a manner different from that in the nucleus in the murine hippocampus.