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Biomedical subjects

F Wu

Publications and source records attributed to F Wu.

At least 109 records · Page 6Linked to original sources
PubMed1999

Changes in functional glutamate receptors on a postsynaptic neuron accompany formation and maturation of an identified synapse.

N-Methyl-D-aspartate (NMDA)-type glutamate receptors play important roles at developing synapses and in activity-dependent synaptic plasticity. Recent studies in Aplysia suggest that NMDA-like receptors may contribute to some forms of plasticity of sensorimotor synapses accompanying associative learning. We examined at various times after plating neurons in culture the contribution of NMDA- and alpha-amino-3 hydroxy-5 methyl-4 isoxazole proprionic acid (AMPA)-like glutamate receptors to responses evoked in motor cell L7 either by action potentials in sensory neurons (SNs) or by focal applications of glutamate. We found that (D,L)-2-amino-5-phosphopentoic acid-sensitive receptors contributed significantly to postsynaptic responses in 1-day cultures but contributed little in the same cultures on day 4. By contrast, postsynaptic responses on day 4 increased significantly in amplitude by the addition of functional 6-cyano-7 nitroquinoxaline-2,3-dione- or 1-(4-aminophenyl)-4-methyl-7,8-methylendioxy-5H-2,3-benzodiazepine hydrochloride-sensitive receptors. Receptors with NMDA-like properties are detected on day 1 only at sites on L7 apposed to SN varicosities, and are not detected on L7 cultured alone. The results indicate that changes in expression and distribution of functional receptors on L7 accompany the formation and maturation of SN synapses. Signals from the SN appear to trigger expression and clustering of functional NMDA-like receptors at sites contacted by presynaptic structures capable of transmitter release. With time, functional AMPA-like receptors are added to these sites enhancing synaptic efficacy. The results are consistent with the idea that the expression and sequential clustering of NMDA- and AMPA-type receptors may be essential for the formation and maturation of central synapses.

2-Amino-5-phosphonovalerate↗
PubMed1999

[High-level expression of human acidic fibroblast growth factor in E. coli and its purification].

A reconstructed human acidic fibroblast growth factor (haFGF) cDNA was cloned into the expression vector pkk223-3, and the expression in Escherichia coli. JM109 was induced by IPTG induction; the expression level of the recombinant haFGF was about 80 mg/L. The expressed haFGF was purified to identity by heparin affinity chromatography and the recovery rate of haFGF was 65%. The specific activity of the purified haFGF was ED50 4.6 ng/ml. The characters of recombinant haFGF was identical to that of natural one.

Cloning, Molecular↗
PubMed1999

[A comparative study of finger plethysmography and aortic pressure for monitoring the effect of external counterpulsation].

Invasive pressure detecting and monitoring of aortic root was conducted in 20 volunteers so as to study the effect of Enhanced External Counterpulsation (EECP) on aortic pressure and finger plethysmography. The results demonstrated that the changes of aortic diastolic pressure linearly related to the counterpusation's bladder pressure, and the aortic augmentation increased to the top of 168.56 mmHg with a D/S ratio of 2.75(amplitude ratio of diastolic waveform and systolic waveform, D/S ratio) following the bladder pressure of 0.45 Kg/cm2. With the increase of bladder pressure, the dp/dt of aortic augmentation elevated gradually, but a down-regulating trend was seen in systolic waveform. During EECP, the starting time of plethysmographic augmentation had a mean delay of 108.20 +/- 25.70 ms comparing with that of aortic augmentation. The duration between the starting time of aortic systolic waveform and that of finger plethysmogram was arround 96.69 +/- 38.70 ms. When the bladder pressure changed, no significant difference was observed among them. The D/S ratio of finger plethysmographic waveform changed in concord with that of aortic pressure with the promotion of bladder pressure. Therefore, a relationship between aortic D/S ratio (Y) and plethysmographic D/S ratio (x) was constructed by the linear regression analysis: Y = 0.376 + 0.457X. It can be concluded that EECP has significant effects on aortic D/S ratio, aortic peak augmentation and its dp/dt value. Finger plethysmography, to date, still plays important roles in monitoring and controlling EECP work safely and effectively.

Adolescent↗
PubMed1999

Diagnosis of trichinosis by indirect fluorescent antibody test with Trichinella larva section.

AIM: To evaluate the value of indirect fluorescent antibody test (IFAT) in diagnosing trichinosis. METHODS: IFAT using frozen section of the purified Trichinella larvae as antigen was employed to detect anti-Trichinella antibodies in sera from mice infected with Trichinella spiralis and the patients with trichinosis. Sera from patients with trichinosis were collected at different time intervals after onset of the disease and after treatment with albendazole. Sera from patients with other parasitic diseases and healthy individuals were used as control. RESULTS: The anti-Trichinella antibodies were detected in 15 infected mice as early as 2 weeks after infection, and in 86.5% of 467 patients with trichinosis. Sera from patients with filariasis, echinococcosis and healthy controls were all negative. 8 of 48 (16.7%) cases with paragonimiasis showed positive cross reaction. The antibody positive rate of patients with trichinosis was 70.2% one week after onset of disease and increased to 91.0%, 95.8% and 100% at two, three and four weeks after onset, respectively. The frozen section of the larvae can be stored at -20 degrees C for 5 years without loss of antigenicity. The IFAT positive rate was increased from 87.5% before treatment to 100% one week after treatment, and the serum antibody titers were elevated as well. The antibody negative conversion rate of the patients was 24% at one month after teratment and increased to 75% at four months after treatment. CONCLUSION: IFAT using frozen section of the purified Trichinella larvae as antigen is highly sensitive and specific for the diagnosis of trichinosis and evaluation of the therapeutic effect.

Animals↗
PubMed1998

Analysis of neuronal nitric oxide synthase isoform expression and identification of human nNOS-mu.

The neuronal form of nitric oxide synthase (nNOS) is responsible for the production of NO, which acts as a neurotransmitter for penile erection and urethra relaxation. An nNOS splice variant form, nNOS-mu, was first reported to be specifically expressed in skeletal muscle and heart in the rat, but later also identified in rat penile cavernosum. We report here an apparently universal expression of nNOS-mu mRNA in rat tissues, including brain, which was previously reported to be lacking nNOS-mu. Immunoblot analysis revealed that some commercially available nNOS antibodies had high levels of nonspecific activities, which could lead to the appearance of seemingly multiple forms of nNOS. Immunohistochemical analysis with these antibodies also produced nonspecific stainings. In humans, nNOS-mu; expression appeared to be confined to skeletal muscle and heart. Human penile tissues obtained from patients with erectile dysfunction did not express nNOS-mu. The human nNOS-mu-specific cDNA sequence was 89% homologous to its rat counterpart.

Alternative Splicing↗
PubMed1998

Epidemiological, clinical and serological studies on trichinellosis in Henan Province, China.

The epidemiological, clinical and serological studies on human trichinellosis in Henan Province were carried out from January 1992 to December 1996. The results showed that 467 patients attending our department came from 12 administrative areas and cities of the Province and they acquired the infection mainly by eating undercooked dumplings, tasting the raw pork filling for dumplings, ingesting scalded pork or mutton. There was the high incidence season of trichinellosis during the winter. Most of the patients were workers, officers and merchants aged 20-49 years, and the incidence was higher in males than in females. The main clinical manifestations of trichinellosis were fever, general myalgia, muscle tiredness and eosinophilia. Most of the patients had not any gastrointestinal symptoms and rash. Eyelid edema was only seen in the early courses of the disease. Eosinophil count increased with time, reached to the peak 3 weeks and decreased markedly 6 weeks after the onset of the disease. Eosinophil levels elevated obviously 1 week after therapy, began to drop rapidly 2 weeks after therapy, and decreased to a near normal levels 4 weeks after therapy. Anti-Trichinella antibodies were detected by IFAT using the frozen sections of the purified T. spiralis larvae as antigen. The specific antibodies were observed in only 70.2% of patients one week after onset of disease, and increased to 91, 94.3, and 100%; 2, 3, and 4 weeks, respectively after the onset. The antibody positive rate was evidently increased to 100% 1 week after therapy with abendazole, then decreased to 25% 4 months after therapy.

Adolescent↗
PubMed1998

Identification of AP-2 as an interactive target of Rb and a regulator of the G1/S control element of the hamster histone H3.2 promoter.

Previous studies have established that a 32 bp cis -regulatory region, referred to as the H3core spanning -241 to -210 of the hamster histone H3.2 promoter, is critical for its G1/S-phase induction of transcription. Here we report that the transcription factor AP-2 is a major component of the protein complex which interacts with the H3core from hamster nuclear extracts. In search of the control mechanism(s) whereby AP-2 can mediate cell cycle regulation of the histone H3.2 promoter, we found that AP-2 can physically interact with the retinoblastoma (Rb) tumor suppressor protein in vitro , and when over-expressed, can also associate with Rb in vivo . Importantly, in contrast to the majority of Rb binding proteins, the C-terminal domain of Rb alone is sufficient for its interaction with AP-2. Using a reporter gene system linking tandem copies of the H3core to a heterologous minimal promoter, we demonstrated that over-expression of AP-2 proteins results in transactivation of the reporter gene through the H3core in a sequence-specific but orientation-independent manner. Additionally, this stimulative effect was suppressed by co-expression of Rb. Thus, AP-2, through its physical and functional interaction with Rb, may contribute to the cell cycle regulation of its target genes.

Animals↗
PubMed1998

An outbreak of paragonimiosis in Zhengzhou city, China.

An outbreak of paragonimiosis occurred in the city of Zhengzhou, Central China, in May 1995. Of seven exposed urban inhabitants, four were seropositive for Paragonimus and had clinical symptoms consistent with acute paragonimiosis. All of four cases treated were cured with praziquantel. The P. skrjabini adult worm was obtained from the rats experimentally infected with the crabs collected in the mountainous area where the urban inhabitants had got the infection. The outbreak was attributed to the intake of raw freshwater crabs while on tourist trips in a mountainous area.

Adolescent↗
PubMed1998

Control of breast tumor cell growth using a targeted cysteine protease inhibitor.

The purpose of this study was to determine whether inhibition of lysosomal proteolysis could be used to selectively inhibit proliferation of tumor cells. The lysosomal cysteine protease inhibitor 9-fluorenylmethyloxycarbonyl-tyrosylalanyl-diazomethane was found to inhibit growth of the breast cancer cell lines SK-Br-3 and MCF-7. A humanized monoclonal antibody (huMAb 4D5) directed against the extracellular domain of p185HER2 specifically inhibited growth of the SK-Br-3 cells, which overexpress this antigen. The antibody and inhibitor together showed enhanced inhibition of growth of the SK-Br-3 cells only. When the protease inhibitor was radiolabeled and conjugated to the antibody (huMAb 4D5-125I-Tyr-Ala-CHN2) it was selectively bound to and taken up by the SK-Br-3 cell line. The conjugated inhibitor was delivered and targeted to cathepsin B and an unidentified protein of Mr 39,000 in the SK-Br-3 cells. Internalization of huMAb 4D5-125I-Tyr-Ala-CHN2 and inhibitor labeling of the proteins were temperature-dependent processes. huMAb 4D5-Tyr-Ala-CHN2 was significantly more effective in inhibiting proliferation of SK-Br-3 cells than the inhibitor-free analogue but was ineffective against MCF-7 cells. The results in this report show that targeting of cysteine protease inhibitors can selectively control tumor cell growth and that targeted cysteine protease inhibitors could prove valuable in the development of novel anticancer immunotherapies.

Antibodies, Monoclonal↗
PubMed1998

Thioltransferase is present in the lens epithelial cells as a highly oxidative stress-resistant enzyme.

The redox homeostasis is controlled by several enzyme systems. Sulfhydryl groups in lens proteins are very sensitive to oxidative stress and can easily conjugate with nonprotein thiols (S-thiolation) to form protein-thiol mixed disulfides. We have observed an elevation of protein S-S-glutathione (PSSG) and protein-S-S-cysteine (PSSC) in cataractous lenses from humans and from animal models subjected to oxidative stress. We also observed that these protein-thiol mixed disulfides could be spontaneously dissociated and lowered to basal levels if the lens which was pre-exposed to H2O2 was subsequently cultured in H2O2-free medium. This suggests that the lens has a system to repair oxidative damage through dethiolation thereby restoring its redox homeostasis. In other tissues, an enzyme, thioltransferase (TTase), has been shown to be responsible for thiol/disulfide regulation. We recently demonstrated the presence of this enzyme in the lens and in cultured lens epithelial cells. Here, we investigated the response of TTase to H2O2 stress and its possible repair function in cultured lens epithelial cells. Rabbit lens epithelial cell line N/N 1003A was raised to confluence, trypsinized and plated at 0.8 million cells per 60 mm culture dish. The cells were incubated overnight in Eagle's minimum essential medium (MEM) with 1% rabbit serum and then in serum-free MEM for 30 min before a bolus of 0.5 mm H2O2 was added. At intervals of 5, 15, 30 min and up to 3 hr, the cells were harvested and used for enzyme assays for TTase, glutathione reductase (GR), glutathione peroxidase (GPx) and glyceraldehyde-3-phosphate dehydrogenase (G-3PD). Free GSH, total SH and PSSG and PSSC were also determined. Hydrogen peroxide in the medium was measured at each time point. Cells incubated without H2O2 were used as controls. The results showed that the H2O2 concentration was reduced to 50% within 30 min and was undetectable at 2 hr. Cellular GSH dropped to 40% within 5 min and stayed at this level before it began to increase at 90 min and completely recovered by 2 hr. The total SH groups were similar to free GSH. PSSG and PSSC increased 6.5 and 2 times respectively before 30 min and then decreased when GSH started to recover. G-3PD was most sensitive to H2O2 and lost 95% activity within 5 min. The activity was regained quickly when H2O2 diminished in the medium. A similar but less severe pattern was observed in both GPx (60% loss at 60 min) and GR (30% loss at 90 min). In contrast, TTase activity remained constant during the entire 3 hr. Only when a higher dose of H2O2 (0.8-1.0 mM) was used, did TTase activity show a brief loss (<30% at 60 min) and a swift recovery. Cells exposed to H2O2 exhibited a normal morphology with no evidence of DNA fragmentation. The lens epithelial cells showed a remarkable ability to repair the early damages induced by H2O2. The unusual oxidative stress-resistant property displayed by TTase, coupled with its known function suggest that it plays an important role in the repair of oxidative damage.

Animals↗
PubMed1998

Domain structure and molecular conformation in annexin V/1,2-dimyristoyl-sn-glycero-3-phosphate/Ca2+ aqueous monolayers: a Brewster angle microscopy/infrared reflection-absorption spectroscopy study.

Annexins comprise a family of proteins that exhibit a Ca2+-dependent binding to phospholipid membranes that is possibly relevant to their in vivo function. Although substantial structural information about the ternary (protein/lipid/Ca2+) interaction in bulk phases has been derived from a variety of techniques, little is known about the temporal and spatial organization of ternary monolayer films. The effect of Ca2+ on the interactions between annexin V (AxV) and anionic DMPA monolayers was therefore investigated using three complementary approaches: surface pressure measurements, infrared reflection-absorption spectroscopy (IRRAS), and Brewster angle microscopy (BAM). In the absence of Ca2+, the injection of AxV into an aqueous subphase beneath a DMPA monolayer initially in a liquid expanded phase produced BAM images revealing domains of protein presumably surrounded by liquid-expanded lipid. The protein-rich areas expanded with time, resulting in reduction of the area available to the DMPA and, eventually, in the formation of condensed lipid domains in spatial regions separate from the protein film. There was thus no evidence for a specific binary AxV/lipid interaction. In contrast, injection of AxV/Ca2+ at a total Ca2+ concentration of 10 microM beneath a DMPA monolayer revealed no pure protein domains, but rather the slow formation of pinhead structures. This was followed by slow (>2 h) rigidification of the whole film accompanied by an increase in surface pressure, and connection of solid domains to form a structure resembling strings of pearls. These changes were characteristic of this specific ternary interaction. Acyl chain conformational order of the DMPA, as measured by nu(sym)CH2 near 2850 cm(-1), was increased in both the AxV/DMPA and AxV/DMPA/Ca2+ monolayers compared to either DMPA monolayers alone or in the presence of Ca2+. The utility of the combined structural and temporal information derived from these three complementary techniques for the study of monolayers in situ at the air/water interface is evident from this work.

Annexin A5↗
PubMed1998

LEA-1/ICAM-1 interaction is essentially involved in the pathogenesis of delayed-type hypersensitivity-induced liver injury to picryl chloride.

The kinetics of lymphocyte function associated antigen 1 (LFA-1) expression on spleen cells (SPC) and liver non-parenchymal cells (NPC), and intercellular adhesion molecule 1 (ICAM-1) expression on hepatocytes (HC) was examined in acute liver injury mice induced by a DTH reaction to picryl chloride (PCl). The peak expression of LFA-1 on SPC was seen at 6 hr after eliciting liver injury, and then that of LFA-1 on NPC and ICAM-1 on HC appeared at 12 hr. Thereafter, the serum ALT elevation reached to a peak at 18 hr. A splenectomy before the PCl elicitation significantly reduced the ALT elevation. Both SPC and NPC from liver injury mice induced a remarkable release of ALT from HC in vitro, in parallel with their LFA-1 expression. The pre-treatment of NPC or SPC with anti-LFA-1 mAb, irrespective of the presence of complement, completely blocked the ALT release. Also, when HC was prebound with anti-ICAM-1 mAb, neither NPC nor SPC showed a cytotoxicity against the HC. Furthermore, the treatment of NPC with either anti-Thy1.2 or anti-CD4 mAb in the presence but not absence of complement, showed a complete abolishment of ALT release. Anti-CD8 mAb plus complement also tended to inhibit ALT release. The twofold increase in CD4+ LFA-1+ and mild increase in CD8+ LFA-1+ populations were also confirmed in NPC at 12 hr. These results suggest that PCl elicitation in liver may trigger an increased expression of LFA-1 on SPC and NPC and ICAM-1 on HC. LFA-1/ICAM-1 interaction between liver-infiltrating NPC, mainly including CD4+ and CD8+ T cells, and HC may be an essential step for the hepatocyte damage in PCl-DTH liver injury.

Alanine Transaminase↗
PubMed1998

Role of CD4+ and CD8+ T cells in regulating the chronic development of liver injury induced by delayed-type hypersensitivity to picryl chloride.

In this study we first investigated the cellular immune responses in mice with chronic liver injury induced by delayed-type hypersensitivity to picryl chloride (PCl). A continuous reduction, after week 3 of liver injury, was observed in the level of PCl-induced contact sensitivity but not in sheep red blood cell-induced footpad reaction, suggesting the presence of PCl-specific suppression. When spleen cells from mice whose liver had been injured for 1 week were systemically transferred into syngeneic recipients with the liver injury, the elevation in serum lactic dehydrogenase and the decrease in alkaline phosphatase and albumin levels in recipient mice were significantly exacerbated. However, when the liver damage in the donor mouse was allowed to proceed for 3, 5 or 7 weeks, biochemical changes in recipients were reduced to near normal levels. A flow-cytometric assay demonstrated that the number of CD4+ T cells in both spleen cells and liver nonparenchymal cells decreased dramatically during the late phase of liver injury, while CD8+ counts did not. These findings suggest that CD4+ and CD8+ T lymphocytes may contribute to the positive and negative regulation, respectively, of the early and late phases in the chronic development of liver injury.

Animals↗
PubMed1998

Protective effect of angiotensin II-induced increase in nitric oxide in the renal medullary circulation.

This study examined the effect of intravenous infusion of subpressor doses of angiotensin (Ang II) on renal medullary blood flow (MBF), medullary partial oxygen pressure (PO2), and nitric oxide (NO) concentration under normal conditions and during reduction of the medullary nitric oxide synthase (NOS) activity in anesthetized rats. With laser Doppler flowmetry and polarographic measurement of PO2 with microelectrodes, Ang II (5 ng/kg per minute) did not alter renal cortical and medullary blood flows or medullary PO2. N(omega)-nitro-L-arginine methyl ester (L-NAME) was infused into the renal medullary interstitial space at a dose of 1.4 microg/kg per minute, a dose that did not significantly alter basal levels of MBF or PO2. Intravenous infusion of Ang II at the same dose in the presence of L-NAME decreased MBF by 23% and medullary PO2 by 28%, but it had no effect on cortical blood flow or arterial blood pressure. An in vivo microdialysis-oxyhemoglobin NO trapping technique was used in other rats to determine tissue NO concentrations using the same protocol. Ang II infusion increased tissue NO concentrations by 85% in the renal cortex and 150% in the renal medulla. Renal medullary interstitial infusion of L-NAME (1.4 microg/kg per minute) reduced medullary NO concentrations and substantially blocked Ang II-induced increases in NO concentrations in the renal medulla, but not in the renal cortex. Tissue slices of the renal cortex and medulla were studied to determine the effects of Ang II and L-NAME on the nitrite/nitrate production. Ang II stimulated the nitrite/nitrate production predominately in the renal medulla, which was significantly attenuated by L-NAME. We conclude that small elevations of circulating Ang II levels increase medullary NO production and concentrations, which plays an important role in buffering the vasoconstrictor effects of this peptide and in maintaining a constancy of MBF.

Angiotensin II↗
PubMed1998

Neutrophil apoptosis during the development and resolution of oleic acid-induced acute lung injury in the rat.

The oleic acid (OA) model of acute lung injury in rats is characterized by a massive and rapid influx of polymorphonuclear neutrophils (PMN) within 1 h, with a peak inflammatory response at 4 h and resolution by 72 h. We hypothesized that PMN apoptosis is involved in the resolution of OA-induced acute lung injury. To test this hypothesis, healthy adult Fischer 344 rats were given 30 microl OA in 0.1% bovine serum albumin (BSA) intravenously; controls were given BSA alone and killed at 1, 4, 24, and 72 h after OA to obtain bronchoalveolar lavage fluid (BALF) and lung tissue. Cell pellets from BALF and formalin-fixed, paraffin-embedded tissue section samples were processed for terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) to identify apoptotic cells. Propidium iodide was used to counterstain nuclei. Percentage of nuclei undergoing apoptosis was counted under a fluorescent microscope. Control rats showed only resident alveolar macrophages (AM) in the BALF with no apoptosis. At the peak of injury, 1 h and 4 h after OA injection, we observed a massive PMN response without any evidence of apoptosis. At 24 h, when the OA injury is clinically and histologically in early resolution, we observed intense apoptosis of PMN nuclei along with evidence of apoptotic bodies in the cytoplasm of AM. Some of the AM also showed apoptotic nuclei at 72 h. Similar observations were made in the lung tissue sections. The results of the TUNEL assay were confirmed by DNA ladders and electron microscopy. We conclude that apoptosis of PMN and clearance by AM is an important mechanism in resolution of OA- induced acute lung injury.

Animals↗
PubMed1998

Ontogeny of apoptosis during lung development.

Apoptosis has been shown to be involved in several processes during embryogenesis, but the ontogeny of apoptosis during lung development ahs not been studied. The goals of the current study were to determine if apoptosis occurs during lung development, and to determine the ontogeny of the changes in apoptosis that occur. We studied the ontogeny of apoptosis in vivo using lungs from 14-18-d gestation fetal rats, newborn rats, and 1-d-, 2-d-, 5-d-, and 10-d-old rat pups. Apoptosis was assessed by electron microscopy and the terminal deoxyribonucleotidyl transferase dUTP nick end-labeling assay. We compared the in vivo results with explants of 14-d gestation fetal rat lung placed in culture for 1-4 d because the biochemical development of the lung in organ culture has been shown to closely parallel the development of the lung in vivo. We found apoptosis of mesenchymal cells at the periphery of distal lung buds in early fetal lung (14-16-d gestation). Apoptosis of both mesenchyme and epithelium was present in later fetal lung (18-d gestation). There were no qualitative differences in apoptosis between in vivo fetal lung and explant cultures of fetal lung. There was a 14-fold increase in apoptosis at birth and in the first postnatal day of life (9-12% of cells) compared with fetal lung (0.6-1% of cells). This was followed by a rapid decline in the percentage of apoptotic cells to fetal levels at postnatal d 2-10. We conclude that apoptosis occurs in a spatially, temporally, and cell-specific manner during lung development. The number of cells undergoing apoptosis increases dramatically in the first day after birth.

Animals↗
PubMed1998

[Effects of millimeter wave irradiation with different frequency and power density on their offsprings in mice].

OBJECTIVE: To determine the threshold of millimeter wave irradiation leading to fetal damage in mice and to clarify the mechanism of decrease in their learning and memory function. METHODS: Pregnant mice were irradiated by millimeter wave with frequencies of 37.4, 42.2, 53.0 and 60.0 GHz at power densities of 1 to 8 mW/cm2 for two hours daily from the 6th to 15th day of their gestation. Learning and memory functions of their offsprings were tested by a Y-type electric maze. M-cholinergic receptor (M-R), monoamine transmitter and arginine vasopressor (AVP) in the brain were determined for their offsprings by receptor radiation binding analysis (RBA), high performance liquid chromatography-electrochemical detection (HPLC-ECD) and radioimmunoassay (RIA). RESULTS: The minimal power density of millimeter wave of 37.4, 42.2, and 53.0, 60.0 GHz causing the decrease in learning and memory function, increase of Bmax in the hippocampus and decrease in dopamine (DA) in the brain of the adult offspring mice was five and three mW/cm2 and that causing the decrease in AVP in the hypothalamus was eight and five mW/cm2. Severity of damage in fetal offspring mice caused by irradiation increased with the power density of millimeter wave. Millimeter wave could not cause the increase of their body temperature in pregnant mice. CONCLUSION: Threshold of millimeter wave with frequencies of 37.4, 42.2 and 53.0, 60.0 GHz causing fetal damage in mice was three to five mW/cm2 and one to three mW/cm2, respectively. The decrease in learning and memory functions in offspring mice related with lowering of AVP and DA in the brain and of activity in cholinergic nerve. All these were caused by the non-thermal effects of millimeter wave without a frequency-specific pattern.

Animals↗