[Intracranial plasma cell granuloma: a case report]

Plasma cell granuloma occurs most frequently in the lung and upper respiratory tract; fewer than ten cases have been reported to occur in the central nervous system. A case of intracranial plasma cell granuloma in a 69-year-old male was reported. He visited our clinic, complaining of progressive visual disturbance. The CT in this patient showed a suprasellar mass, diagnosed as a tuberculum sellae meningioma. Over a 10-year observation period the tumor grew remarkably and, when finally removed, it proved to be a plasma cell granuloma. This report presents CT scans and MR images and a review of the literature relevant to this rare intracranial lesion. The most common preoperative diagnosis in these cases, as reported here, was meningioma. Although plasma cell granuloma rarely occurs intracranially, the existence of this entity should be borne in mind in the differential diagnosis of meningioma.

Effects of seishin-renshi-in and Gymnema sylvestre on insulin resistance in streptozotocin-induced diabetic rats

Although there is no concept of insulin resistance in traditional Kampo (Chinese) medicine and Indian medicine, we had the hypothesis that some drug in a mixture of crude drugs which was believed to ameliorate diabetes mellitus may have had the effect of improving insulin resistance. To test this hypothesis, the effects of Seishin-renshi-in (Chinese medicine) and Gymnema sylvestre (Indian medicine) on the insulin resistance of streptozotocin-induced diabetic rats was studied by the glucose clamp technique. Oral administration of Seishin-renshi-in (800 mg/kg/day) with injections of a minimum dose of Ultralente insulin decreased urine volume and urinary glucose excretion during a 7-day treatment period and improved the insulin stimulated glucose uptake in peripheral tissues, as well as improving the insulin suppressed hepatic glucose output during glucose clamp. However, G. sylvestre (120 mg/kg/day) treatment did not improve insulin resistance. We conclude that Seishin-renshi-in, with a small dose of insulin, improved insulin resistance in streptozotocin-induced diabetic rats, but Gymnema sylvestre did not.

A-band movement and junctional gap dissociation during caffeine-induced contracture of skeletal muscle fibers

The action of caffeine on the myofibril profile of the sarcomere and the junctional gap of the intracellular membrane was studied ultrastructurally. When a high concentration of caffeine (5 mM) was applied, the movement of the A-band in sarcomeres dissected from the central portion of single muscle fibers was greater than that in sarcomeres dissected from the proximal and distal portions of the fiber. The amount of calcium released from the sarcoplasmic reticulum of the caffeine-treated muscle was greater in the terminal cisternae located on the narrow I band than in the wide I band, as determined by electron-probe analysis of ultrathin cryosections. The junctional gap was clearly expanded after caffeine treatment, resulting in an irreversible change in muscle contractility. These structural alterations may lead to the distinctive development of tension induced by caffeine. The expansion of the gap may also cause excitation-contraction uncoupling.

Total body fat estimations by near-infrared interactance, A-mode ultrasound, and underwater weighing

We studied 94 (41 men and 53 women) healthy 18 to 65 years old Caucasians for body composition utilizing 3 methods: 1) Underwater weighing (UWW) for body density, 2) A-mode ultrasound subcutaneous fat determination, and 3) Near-infrared (NIR) interactance spectral data. We then utilized the Wherry-Doolittle test selection method to predict percent of total body fat (%fat) from either ultrasound or NIR data with anthropometric measurements, optimizing for the fewest number of data points which correlated highly with UWW results. It was found that %fat could be estimated with a correlation of > 0.9 when measured at 4 sites (different between men and women) by ultrasound, age (women) and height (men). We also found a correlation of > 0.8 using 2 sites by NIR, weight, age, and height. It has been suggested that the ultrasound method would produce better estimates of both local and total body fat.

ECG differentiation of idiopathic dilated cardiomyopathy from coronary artery disease with left ventricular dysfunction

To elucidate electrocardiographic differences of dilated cardiomyopathy (DCM) and coronary artery disease (CAD) with left ventricular (LV) dysfunction, 12-lead electrocardiograms in 23 patients with DCM, 36 patients with CAD and LV dysfunction, and 63 normal subjects were analyzed. Abnormal Q waves were seen in 69% of CAD patients and in 26% of DCM patients. Abnormal Q waves in leads II, III, aVF, or V2-V4 were present in 61% of CAD patients compared with 4% of DCM patients (P < .001). The R wave in lead RV6 voltage in DCM was the highest among the three groups and correlated with the degree of LV dilatation. RV6 voltage in CAD was the lowest and decreased in proportion to the severity of the apical thallium-201 defect RV6 voltage of 15 mm or more was present in 78% of DCM patients compared with 11% of CAD patients (P < .001). The R waves in leads I, II, and III (RI, RII, RIII) were also low in DCM. Therefore, all voltage ratios of RV6/RI, RII, RIII were the highest in DCM. In particular, the ratio of RV6 over the maximum R wave in leads I, II, and III (RV6/Rmax) in DCM correlated with the degree of LV dilatation and inversely with ejection fraction. RV6/Rmax was significantly higher in the DCM group compared with the CAD and control groups (3.3 vs 1.2, 1.2, respectively; P < .001). This ratio of 3 or more was present in 61% of the DCM patients but in none of the CAD patients or normal subjects (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Iron, zinc, and copper levels in different tissues of clinically vitamin A-deficient rats

To clarify the effect of vitamin A deficiency on iron, zinc, and copper status in different tissues, three groups of rats were fed two types of synthetic diets for 52 d. Group one, which was fed a vitamin A-deficient diet, showed severe signs of vitamin A deficiency. Groups two (fed restricted amount, pair-fed with group one), and three (fed diet ad libitum) were fed a control diet. After said period of feeding, iron, zinc, and copper were measured in different tissues. Significant changes observed when the groups were compared are summarized below: 1. Iron and copper in testes were increased significantly, whereas zinc was strikingly decreased in group one when compared with the other groups; 2. Copper (in lung and kidney) and iron (in the spleen) were increased significantly in group one compared with the other groups; 3. In the liver, iron, zinc, and copper were significantly different between group one and group two; 4. In muscle, iron was significantly higher in group one than group two; 5. In tibia and blood, iron levels (but not zinc and copper) in groups one and two were significantly higher than group three. These results suggest that vitamin A deficiency affects iron, zinc, and copper status in rats.

Sleep patterns in cyclic and pseudopregnant rats

In order to clarify the relationship between sleep and reproductive activities, time-course changes in sleep were analyzed in normal female rats. The state of sleep-wakefulness was continuously monitored for 4 weeks including two-consecutive 4-day estrous cycles, a 12-day pseudopregnant period and a subsequent 4-day cycle. Sleep patterns in estrous cycle were characterized by a marked reduction in nocturnal non-rapid-eye-movement sleep (NREMS) and rapid-eye-movement sleep (REMS) at proestrus. A significant increase in nocturnal NREMS and REMS occurred immediately after the induction of pseudopregnancy by sterile mating, lasting for the whole pseudopregnant period for NREMS and during the early and mid period for REMS. In contrast, diurnal REMS tended to decrease towards the end of pseudopregnancy. The circadian rhythm of brain temperature exhibited no reproductive activity-dependent change. The dynamic changes in sleep may correlate alterations in neuroendocrine activities specific to estrous cycles and pseudopregnancy.

Involvement of P-type calcium channels in high potassium-elicited release of neurotransmitters from rat brain slices

Several types of voltage-dependent calcium channels appear to occur in neurons, although coupling of the particular subtype of calcium channels to the release of neurotransmitter has not been clearly understood. We have examined the effects of subtype-specific inhibitors of the calcium channels on depolarization-induced release of endogenous neurotransmitters from brain slices. High potassium-induced release of glutamate and aspartate from hippocampal and striatal slices was almost completely inhibited by a P-type channel blocker, omega-agatoxin IVA. omega-Agatoxin IVA also completely inhibited the release of serotonin from the hippocampal slices with almost the same potency as in the case of glutamate, whereas the potency in blocking the release of serotonin and dopamine from striatal slices was lower than that from the hippocampal slices. Another calcium channel blocker, omega-agatoxin TK, that was recently found to block P-type channels with very similar selectivity and potency to omega-agatoxin IVA, also inhibited the release of amino acid transmitters and monoamines, though its potency was lower than that of omega-agatoxin IVA. An N-type channel blocker, omega-conotoxin GVIA, partially inhibited the neurotransmitter release, but an L-type channel blocker, nifedipine was ineffective. We propose that the activation of P-type calcium channels makes a major contribution to depolarization-elicited neurotransmitter release in the CNS and that multiple P-type channels sensitive to omega-agatoxin IVA and omega-agatoxin TK modulate the neurotransmitter release.

[Hypoglycemic activity and mechanisms of extracts from mulberry leaves (folium mori) and cortex mori radicis in streptozotocin-induced diabetic mice]

Averaged blood glucose levels were 400 mg/dl in nonfasted mice, and 250 mg/dl in fasted mice in 4 weeks after injection with streptozotocin (STZ, 150 mg/kg, i.v.). These mice were used for experiments. Hypoglycemic effects of hot water extracts (W) from Folium Mori (Mulberry leaves, Morus alba L., China and Japan) or Cortex Mori Radicis (Morus alba L., China) were observed in fasted and nonfasted STZ-induced diabetic mice at a single dose of 200 mg/kg (i.p.). The W from Folium Mori exhibited most potent hypoglycemic effects. The most potent fractions of Folium Mori and Cortex Mori Radicis were ethanol-insoluble extracts (A2). These A2 fractions demonstrated a fall in blood glucose levels of 24.6 +/- 6.0% and 60.5 +/- 9.1% at nonfasted STZ-mice, and 81.4 +/- 7.9% and 77.3 +/- 5.8% at fasted STZ-mice, respectively. The increase in glucose uptake was a mechanism of hypoglycemic actions by W and A2 of Folium Mori.

Effects of vitamin B2 on neutrophil functions in cattle

Vitamin B2 was intramuscularly administered to Holstein cattle and the ensuing changes in peripheral blood neutrophil function were investigated. The neutrophil count displayed a significant increase at 1-2 days after administration, while nitroblue tetrazolium reducing activity and phagocytic bactericidal activity were enhanced at 1-4 days after administration in calves and at 1-6 days after administration in adult cows. The increases in the neutrophil count and the activation of neutrophil functions were observed, being manifested at dosages of 10 mg/kg or greater for calves and 5 mg/kg or greater for adult cows.

Indoleamine concentrations in cerebrospinal fluid from patients with Alzheimer type and Binswanger type dementias before and after administration of citalopram, a synthetic serotonin uptake inhibitor

We studied changes in the concentrations of serotonin (5-HT), kynurenine, and other indoleamines in the cerebrospinal fluid of patients with Alzheimer type dementia (ATD) and those with Binswanger type vascular dementia (VDBT), and changes in these indoleamine concentrations 2 weeks after administration of citalopram, a 5-HT uptake inhibitor. The concentrations of total 5-HT (p < 0.005) and kynurenine (p < 0.005) were significantly decreased in ATD patients in comparison to those of the controls. After citalopram administration, there was a remarkable increase in 5-HT concentration (249%, p < 0.0001) and a significant decrease in 5-HIAA concentration (22%, p < 0.02). In the VDBT patients, only 5-HT showed a significant decrease (p < 0.005) in comparison to the control values. It also increased significantly (214%) after citalopram administration. The 5-HT/tryptophan and kynurenine/tryptophan ratios were not correlated for the controls, but did significantly for the ATD and VDBT patients; after citalopram treatment, the increase in 5-HT/tryptophan was correlated significantly with that of kynurenine/tryptophan for ATD, but not for VDBT. These results suggest that both the serotonin and kynurenine pathways are impaired in ATD; whereas, the serotonin pathway alone is in VDBT, and that these impairments are ameliorated by the administration of citalopram.

Androgen regulation of intra-and extra-thymic T cells and its effect on sex differences in the immune system

Male predominance of malignant disease and female predominance of autoimmune diseases is widely known in humans. To elucidate one of the underlying mechanisms, we examined whether sex differences exist at the level of extra-thymic T cells in various organs of mice under physiological conditions. Effects of castration and testosterone administration were also examined. Intra- and extra-thymic T cells with T cell receptors (TCR) of bright and intermediate intensities, respectively, and with nil and high levels of the interleukin-2 receptor beta-chain respectively, were identified by immunofluorescence. Of the three strains tested, it was demonstrated that intermediate TCR cells were predominant in the liver of female mice. In the liver of male mice after bilateral orchidectomy, mononuclear cells increased and intermediate TCR cells predominated as if they were female; testosterone treatment prevented this immunological consequence of orchidectomy. As extra-thymic T cells comprise a considerable proportion of self-reactive forbidden clones and possess cytotoxic activity against syngeneic tumour cells, the present results suggest a possible relationship between (a) physiologically low levels of extra-thymic T cells in males and the male predominance of malignancy, and (b) the high levels of extra-thymic T cells in females and female predominance of autoimmune diseases.

Functional map of the alpha subunit of Escherichia coli RNA polymerase: insertion analysis of the amino-terminal assembly domain

The alpha subunit of Escherichia coli RNA polymerase plays a key role in assembly of the core enzyme. Deletion analysis of alpha indicated that the amino-terminal domain consisting of 215 amino acid residues between positions 21 and 235 is involved in this assembly. For fine mapping of the site(s) within this region required for subunit-subunit contacts, we constructed a set of insertion mutants of the rpoA gene, each encoding mutant alpha with two extra amino acid residues, Ala (A) and Ser (S), inserted at 20 residue intervals. The over-expressed alpha derivatives were purified to apparent homogeneity and examined for their ability to form dimers and to assemble beta and beta' subunits into core enzymes in vitro. Among a total of 11 alpha insertion derivatives tested, four mutants having the insertion at dispersed positions retained the ability to form active core enzymes. Other mutants showed defects in core enzyme assembly at various steps depending on the position of AS insertion: one mutant formed an unstable alpha 2 beta complex; one mutant exhibited decreased binding of beta' subunit; and five mutants did not form stable alpha dimers, of which one formed an alpha 2 beta complex and another formed an alpha beta complex. These results suggest that alpha dimerization involves multiple contact sites. Among alpha mutants with dimer formation ability, the mutation at amino acid residue 80 interfered with the binding of both beta and beta' subunits, and the mutation at position 200 made the alpha dimer inactive in beta' binding.

Cloning and nucleotide sequence of the gene cluster encoding ribosomal proteins S12 and S7 from Mycobacterium bovis BCG

A pair of oligonucleotide primers, based on the experimentally determined amino terminal sequence of Mycobacterium bovis BCG ribosomal protein S12 (MboS12) and a highly conserved sequence found in all mycobacterial ribosomal S12 proteins, was used for polymerase chain reaction (PCR) with M. bovis genomic DNA as template. The nucleotide sequence of the 338 bp fragment thus produced confirmed its origin in MboS12 gene. A 5.0 kb EcoRI fragment of M. bovis DNA hybridizing to this fragment was cloned. Its sequencing analysis revealed the presence of two open reading frames in the same strand. Their amino acid sequences deduced from DNA sequence showed high homology with Escherichia coli ribosomal proteins S12 and S7. However, the intercistronic region between S12 and S7 genes, which plays an important role for autoregulation for the str operon in E. coli, is completely absent in M. bovis.

Depolarizing neuromuscular blocking action of coryneine derived from aconite root in isolated mouse phrenic nerve-diaphragm muscles

The mode of the neuromuscular blocking action of coryneine (a quaternary ammonium derivative of dopamine) derived from aconite root was investigated in isolated phrenic nerve-diaphragm muscles and denervated diaphragm muscles of mice. Coryneine (20-150 microM) blocked the nerve-evoked twitch response without affecting the contraction evoked by electrical stimulation of the muscle. The blocking effect was reversed by neostigmine, a cholinesterase inhibitor. The electrical charge-response curve on depolarization produced by iontophoretically applied acetylcholine (ACh) at the endplate regions in normal muscles was shifted to the right on decreasing the maximal response by 40 microM coryneine. The double-reciprocal plot revealed that coryneine reduced the apparent affinity of ACh for its receptor on decreasing the maximal response. Coryneine (20 microM-2mM) itself depolarized the endplate membrane and this effect was reversibly suppressed by 1 and 5 microM pancuronium. Coryneine 30 microM-10mM) produced contractions of denervated muscles in a concentration-dependent manner and the effects were reduced by 70nM pancuronium. These results indicate that coryneine is a depolarizing agent and a mixed-type competitive and noncompetitive neuromuscular blocker.

[Bioassay for angiogenesis and analysis of its mechanism]

To study the sites of action of cytokines and anti-angiogenic agents, bioassays have been developed to systematically investigate not only the entire process of angiogenesis in vivo but also its individual steps including capillary tube formation and proliferation of vascular endothelial cells (EC). Angiogenesis in vivo is quantitatively assayed by measuring the carmine dye content in Freund's complete adjuvant-induced mouse pouch granuloma after the intravenous administration of dye solution. Angiogenesis in vitro is quantified by counting the number of microvessels developed from blood vessels cultured in fibrin gel. Tube formation is quantitatively estimated by measuring the total length of capillary tubes from EC cultured in type I collagen gel. EC proliferation is assayed by measuring both the increase in cell number and 3H-thymidine incorporation into the cells. The competence and progression activities in the EC proliferation are analyzed by our convenient method. By these bioassays, the mechanism of an anti-differentiation agent can be easily clarified to develop new types of therapies for rheumatoid arthritis and diabetic retinopathy.

Endothelin-1-like immunoreactivity in cerebral cortex of Alzheimer-type dementia

1. Endothelin-1-like immunoreactivity (ET-1-LI) in cerebral cortex in postmortem brains obtained from patients with Alzheimer-type dementia (ATD) was measured by enzyme-immunoassay. 2. The ET-1-LI in the ATD brains was significantly increased in frontal and occipital cortex than those in the control brains and a significant correlation was found between frontal and temporal lobe of ATD brains. 3. These findings may explain the clinico-radiological results that the cerebral blood flow is decreased in ATD patients, the mechanism of which is still unknown.

Comparison of false negative rates among breast cancer screening modalities with or without mammography: Miyagi trial

False negative rates were compared in two screening modalities, physical examination with or without mammography, in an intervention study for women aged over 50 in Miyagi Prefecture. Thirty-five breast cancers were detected in 12,515 subjects who participated in the trial consisting of physical examination and mammography, whereas 44 breast cancers were detected in 50,105 subjects who received physical examination alone, so that the detection rates were 0.28% and 0.09%, respectively. Among 50,061 subjects who received physical examination alone, 8 women were diagnosed as having breast cancer within 12 months after the screening, while only one of 12,480 screenees receiving the combined modality was so diagnosed, implying false negative rates of 15.4% and 2.8%, respectively. When the screening sensitivity in the combined system was analyzed according to each single modality, the false negative rate provided by physical examination with mammography turned out to be 2.8%, significantly lower than that (33.3%) by the physical examination alone. Minimal breast cancers represented 25.7% of all screen-detected cancers in the combined modality, compared with 9.1% in the modality without mammography. The trial thus indicates that physical examination combined with mammography may be an appropriate modality for breast cancer screening in women aged over 50 on the basis of screening sensitivity.

Second look arthroscopy after meniscal repair. Factors affecting the healing rate

Second look arthroscopy was performed on 46 of 137 consecutive patients who underwent arthroscopic meniscal repair. All tears were of the vertical type. Thirty-two tears were located in avascularized areas. Thirty-one patients had associated anterior cruciate ligament insufficiencies. Anterior cruciate ligament reconstructions were performed simultaneously on 26 patients. The double-needle cannula method was used in all the patients. An additional transplantation of a vascularized synovial pedicle flap to the suture site was performed on 7 tears in avascularized areas. Second look arthroscopy showed no healing in 8 patients and healing in 38. Four of the 8 unhealed tears were located in avascularized areas, and 4 had unreconstructed anterior cruciate ligament injuries respectively. All 7 patients with synovial pedicle flaps showed healing. All patients with anterior cruciate ligament reconstructions showed healing, and the healing rate was significantly higher than that of the other patients (p < 0.005). Patients with anterior cruciate ligament insufficiencies showed a significantly lower healing rate than the others (p < 0.005). In patients with tears in avascularized areas, the conventional meniscal repairs showed a lower healing rate than did the repairs with a synovial pedicle transplantation or an anterior cruciate ligament reconstruction (p < 0.005). These results suggest that the most important factors influencing meniscal healing are the presence of anterior cruciate ligament tears, ligamentous reconstruction, and vascularity of the tear site.

Iodothyronine deiodinase activity in methionine-deficient rats fed selenium-deficient or selenium-sufficient diets

We examined the effect of methionine deficiency on iodothyronine 5'-deiodinase activity in selenium-deficient rats or selenium-sufficient rats fed sodium selenate or selenomethionine. Forty-two weanling male Wistar rats were divided into six groups and pair fed the respective purified L-amino acid-based diets for 4 wk. L-methionine concentrations in the diet were 8.0 g/kg for sufficient rats, and 2.0 g/kg for deficient rats. Selenium concentrations in the diet were 0.5 mg/kg (as sodium selenate or selenomethionine) for selenium-sufficient rats and less than 0.005 mg/kg for selenium-deficient rats. Type I 5'-deiodinase activities were significantly lower in liver and higher in kidney of methionine-deficient rats than in those of methionine-sufficient rats fed either the selenium-sufficient or the selenium-deficient diets. The type I 5'-deiodinase activity in brain was significantly lower in the methionine-deficient rats than in the methionine-sufficient rats fed the selenium-deficient diet. Type II 5'-deiodinase activity in brain was significantly higher in the methionine-deficient rats than in the methionine-sufficient rats fed selenium-sufficient diet as sodium selenate. Both thyroxine and 3,3',5-triiodothyronine concentrations in plasma were significantly higher in the methionine-deficient rats than in the methionine-sufficient rats. It is suggested that the methionine deficiency affects the 5'-deiodinase activity and thyroid hormones level in the rats.

Decline of taste sensitivity in protein deficient adult rats

The influence of dietary protein levels on taste sensitivity was studied in adult rats. Low protein diets of 0.0, 2.5, or 5.0% purified egg protein (PEP) were fed to animals for 28 days. Two bottle choice preference tests between aqueous solutions of either 2, 9, 17, or 86 mM sodium chloride and deionized water were conducted in an ascending order on days 14, 16, 18, and 20. Urine samples were collected for zinc and creatinine analysis. Blood samples were also collected for measuring serum zinc and creatinine concentrations. Scanning electron microscopy was performed to observe rats' tongue epithelia. Protein free diet group showed significantly lower taste sensitivity and renal reabsorption rate than other protein containing diet groups, while serum zinc and creatinine concentrations, and creatinine clearance were not affected by dietary protein level. Degeneration of filiform papillae and imperforation of taste pore of fungiform papillae were observed in protein free diet group. This experiment implies at least 2.5% dietary protein is required to manifest normal taste function in the adult.

Loxiglumide, L-364,718 and L-365,260 prevent the inhibition of spontaneous acetylcholine release from the frontal cerebral cortex of freely moving rat peripherally administered with cholecystokinin-8S

We examined the effect of peripheral administration of cholecystokinin (CCK)-8S on spontaneous acetylcholine (ACh) release from the frontal cortex and its prevention by loxiglumide, L-364,718 and L-365,260 in freely moving rats using intracerebral microdialysis. Subcutaneously (s.c.) administered CCK-8S at 10 and 30 micrograms/kg significantly decreased the release of ACh. The inhibitory effect of 10 micrograms/kg (s.c.) CCK-8S was prevented by loxiglumide, a mixed type of CCK-A and -B-receptor antagonist, at 1 mg/kg (intraperitoneal) and 40 micrograms/rat (intracerebroventricular, i.c.v.); L-364,718, a CCK-A-receptor antagonist, at 125 and 250 ng/rat (i.c.v.); and L-365,260, a CCK-B-receptor antagonist at 250 ng/rat (i.c.v.). These results demonstrate that peripherally administered CCK-8S inhibits spontaneous ACh release from the frontal cortex through both central CCK-A (mainly) and -B receptors.

Synchronous expansion of intermediate TCR cells in the liver and uterus during pregnancy

The immunophysiology of pregnancy was investigated in relation to how extra- and intrathymic pathways of T cell differentiation are modulated during pregnancy. Pregnancy was produced in syngeneic and allogeneic combinations in mice. In both cases, a prominent decrease in the number of thymocytes and a mild increase in the number of hepatic mononuclear cells (MNC) were induced during the periparturient period. The most striking change was the increase in the number of intermediate TCR cells with extrathymic T cell properties in the liver. When MNC yielded by the uterus were examined, an expansion of intermediate TCR cells was also observed in this organ during pregnancy. The major populations in the pregnant uterus were NK cells and intermediate TCR cells, the latter of which contained double-negative CD4-8- cells and consisted of both alpha beta and gamma delta T cells. All of these properties coincided with those of extrathymic T cells in the liver. Reflecting extrathymic T cell differentiation, MNC in the liver and pregnant uterus expressed mRNA of RAG-1 and RAG-2. To determine the role of hormonal regulation in this phenomenon, the effects of various pregnancy-associated hormones on thymocytes and hepatic MNC were examined in nonpregnant mice. Of the hormones tested, estrogen was found to induce a response similar to that seen in pregnant mice. These results suggest that a local immune response in the uterus during pregnancy is a phenomenon occurring synchronously with systemic immune systems.