[Effects of aging on right and left ventricular function in patients with right bundle branch block]

The effect of aging on cardiac function in patients with right bundle branch block (RBBB) was commonly unknown, so left ventricular function and right ventricular function were investigated, using first-pass radionuclide angiography. Twenty-six patients with RBBB and 28 normal subjects were studied at rest and during bicycle exercise. Patients with RBBB but normal cardiovascular systems aged 33 to 75 years were divided into those within 60 years (n = 17) and those over 65 years (n = 9). Using the same method, normal subjects aged 38 to 83 years were divided into those within 60 years (n = 18) and those over 65 years (n = 10). Mean age between normal subjects and patients with RBBB didn't differ significantly. The response of left ventricular ejection fraction in normal groups rose during exercise, but its exercise tolerance function declined with aging. Left ventricular diastolic filling in normal groups declined at rest and during exercise with aging. Left ventricular function in RBBB groups showed the same results as those of normal groups. The response of right ventricular ejection fraction and its exercise tolerance function in normal groups was not influenced by aging. However, in contrast, right ventricular function in RBBB groups decreased with aging. We suggest that the mechanism of decrease of right ventricular function in aging patients with RBBB may be caused by the change of right ventricular contraction which is affected by the aging process.

[The effect of human growth hormone on protein metabolism in the surgically stressed state]

The effects of human growth hormone (HGH) on protein metabolism were investigated. In the experimental study, thirty one male SD rats receiving TPN were divided into 2 groups (control group & HGH group). Cumulative nitrogen balance after burn in HGH group was significantly higher than in control group. (p less than 0.05) Rates of whole body protein turnover (Q), together with those of synthesis (S) and breakdown (B) were significantly higher in HGH group than in control group. (p less than 0.01) Nitrogen balance significantly correlated with urinary total catecholamine excretion in both groups. (p less than 0.01) The difference of correlations of nitrogen balance to urinary total catecholamine excretion between two groups was statistically significant (p less than 0.01) when compared by analysis of covariance. In the clinical study, 12 patients after sub-total esophagectomy receiving TPN were divided into 2 groups (control group & HGH group). Cumulative nitrogen balance after operation in HGH group was significantly higher than in control group. (p less than 0.01) Q,S, and B were higher in HGH group than in control group. Increase of S was statistically significant. (p less than 0.01). These results indicate that HGH may be greatly beneficial in improving protein metabolism in the surgically stressed state.

HLA-DR gene frequencies in the Japanese population obtained by oligonucleotide genotyping

We determined HLA-DRB types of 375 randomly chosen healthy Japanese donors using a set of 29 different sequence-specific oligonucleotide (SSO) probes directed against various DRB alleles. Except for a few cases, these SSOs enabled us to identify 33 different DRB types including those detectable only by SSO genotyping. Gene frequencies were calculated for each of the DRB types identified. The "blank" frequency calculated by our SSO typing was essentially zero, in contrast to the considerably high "blank" frequencies reported at serological HLA-DR or cellular HLA-D workshops. This indicates that almost all of the DRB types in the Japanese population are positively detectable by our SSO typing. By comparing the gene frequencies for each of the DR types obtained by our SSO typing with those obtained by immunological typing at workshops, significant differences were observed for several of the DR types.

Cardiorespiratory responses to standing arm ergometry in patients with ischemic heart disease. Comparison with the results of treadmill exercise

To compare cardiorespiratory responses to standing arm ergometry and treadmill exercise, two graded exercise stress tests were performed in 30 patients with ischemic heart disease (IHD). Cardiac catheterization and expired gas analyses were also done. Standing arm ergometry was discontinued because of arm fatigue in 15 (50%) patients, whereas treadmill exercise was stopped due to leg fatigue in 8 (27%) patients. Maximal increase in rate-pressure product and oxygen uptake, and magnitude of ST-segment depression during standing arm ergometry were significantly smaller (p less than 0.01, p less than 0.01 and p less than 0.05, respectively) than those during treadmill exercise. Furthermore correlations of maximal change in rate-pressure product, oxygen uptake and extent of ST-segment depression were not close between the two exercise tests (r = 0.76, r = 0.67 and r = 0.54, respectively). Our results indicate that the ability to detect IHD with standing arm ergometry is lower than that with treadmill exercise and that it is not possible to predict accurately one's capacity for arm exercise from the treadmill exercise test.

Roles of glutamate receptors in long-term potentiation at hippocampal mossy fiber synapses

We have investigated the roles of glutamate (Glu) receptors in the mechanism of long-term potentiation observed in rat hippocampal mossy fiber synapses (MF-LTP). The mossy fiber responses were almost completely suppressed by ionotropic Glu receptor (iGluR) antagonists both before and after the induction of LTP. However, tetanic stimulation produced robust LTP even when the synaptic transmission was blocked postsynaptically by iGluR antagonists. In contrast, when the transmission was blocked presynaptically by Ca(2+)-free media, tetanic stimulation produced no LTP. D,L-2-amino-3-phosphono-propionate(D,L-AP3), a metabotropic Glu receptor (mGluR) antagonist, inhibited the induction of MF-LTP. Perfusion with ibotenate, a mGluR agonist, induced long-lasting enhancement of the mossy fiber responses without tetanic stimulation, and this ibotenate-induced potentiation was antagonized by D,L-AP3.

Crystal-storing histiocytosis and crystalline tissue deposition in multiple myeloma

Systemic distribution of crystal-storing histiocytes, increasing in number, and widespread crystalline tissue deposition were found in a 75-year-old man with a 5-year history of IgG-kappa-type multiple myeloma associated with corneal opacity and chronic renal failure. Characteristic crystalline inclusions were present not only in myeloma cells but also in cornea, epithelial cells of glomeruli, tubuli, Bowman's capsules, and choroid plexus. Histiocytes had particularly infiltrated the renal interstitium. These inclusions were positive by immunofluorescence for kappa light and gamma heavy chains. By electron microscopy, the inclusions were filled with fine crystalline hexagonal columns, each possessing a core structure. Of various factors generally considered responsible for renal failure in multiple myeloma, marked infiltration of histiocytes and the nephrotoxic effects of light chain appeared most relevant in the present case.

Possible heterogeneity of metabotropic glutamate receptors induced in Xenopus oocytes by rat brain mRNA

Pharmacological properties of metabotropic glutamate receptors were studied in Xenopus oocytes injected with rat brain mRNA. trans-1-Amino-cyclopentyl-1,3-dicarboxylic acid (t-ACPD), a conformationally restricted analog of glutamate, induced oscillatory inward currents in mRNA-injected oocytes. These t-ACPD responses showed several characteristics identical to those of the other metabotropic responses including the metabotropic glutamate responses stimulated by quisqualate. D,L-2-Amino-3-phophonopropionate (D,L-AP3) effectively suppressed the t-ACPD and ibotenate responses. However, quisqualate responses were not affected substantially by D,L-AP3. These findings suggest that the metabotropic glutamate receptors in the oocytes may be classified into at least two subtypes according to their pharmacological properties: one preferentially activated by quisqualate and insensitive to AP3, and the other activated by t-ACPD and ibotenate and antagonized by AP3.

Effects of KN-62, a specific inhibitor of calcium/calmodulin-dependent protein kinase II, on long-term potentiation in the rat hippocampus

Effects of KN-62 (1-[NO-bis-1,5-isoquinolinesulfonyl]-N-methyl-L-tyrosyl- 4-phenylpiperazine), a specific inhibitor of calcium/calmodulin-dependent protein kinase II, were examined using rat hippocampus slices in vitro. The inhibitor, when applied in bathing solutions prior to and present during the tetanic stimulations, blocked the generation of long-term potentiation (LTP) in CA1 regions without affecting basal synaptic transmission itself, suggesting an important role of this kinase in the molecular mechanism of CA1 LTP. In contrast, mossy fiber LTP in CA3 regions was not affected significantly by the inhibitor.

The immunosuppressant FK-506 prevents progression of diabetes in nonobese diabetic mice

A novel immunosuppressive compound, FK-506, isolated from Streptomyces has potent immunosuppressive activities. To investigate the effect of FK-506 on the course of diabetes in nonobese diabetic (NOD) mice, we gave this drug to these animals, from the age of 8 weeks, intraperitoneally, in doses of 0.1 mg (2.5 mg/kg/day) or 0.01 mg (0.25 mg/kg/day) three times a week. Overt diabetes were observed in 75.5% of control mice by the age of 20 weeks. In contrast, no diabetes occurred in mice given 0.1 mg of FK-506. Sixteen percent of mice treated with 0.01 mg of the drug became diabetic. Administration of this drug prevented the progression of insulitis in NOD mice. The mice given 0.1 mg of FK-506 lost weight, but this was reversible.

Sequence analysis and HLA-DR genotyping of a novel HLA-DRw14 allele

Analysis of a Japanese population by oligonucleotide genotyping revealed that one Japanese HLA-DRw14 allele had a DRB1 genotype different from that of the known HLA-DRw14-related alleles, DRB1*1401 (DRw14-Dw9) and DRB1*1402 (DRw14-Dw16). The second exon of the DRB1 gene of the novel DRw14 allele (designated DRB1-14c) was amplified enzymatically and sequenced after cloning into a plasmid vector. The amino acid sequence of the first domain in the DR beta 1 chain encoded in the DRB1-14c allele was more similar to that of the DRB1*1401 allele (three amino acid substitutions) than to that of the DRB1*1402 allele (six amino acid substitutions). No polymorphic amino acid residue that could explain the common serologic HLA-DRw14 specificity was identified among the sequences of the three DRw14-related alleles. Sequence-specific oligonucleotides (SSOs) were synthesized on the basis of the DRB1-14c nucleotide sequence and used for genotyping of the Japanese population. These SSOs served as useful probes for identifying the DRB1-14c allele in a wide range of donors.

Defect of sinusoidal Fc receptors and immune complex uptake in CCl4-induced liver cirrhosis in rats

The purpose of this paper is to provide a histopathologic basis for abnormalities in immune-complex clearance in liver disease. Fc receptors in CCl4-induced liver cirrhosis in rats were studied by applying peroxidase-antiperoxidase immunoglobulin G complex as a ligand to the frozen sections. Intravenous injection of bovine serum albumin-antibovine serum albumin complexes or colloidal carbon was combined with histological staining for endogenous peroxidase, fibronectin, laminin, or a lectin, Bandeiraea simplicifolia agglutinin I. In the cirrhotic process, sinusoidal Fc receptors showed a weakened reactivity to the ligand with focal absence, and the length of the Fc receptor-positive portion of the sinusoids in unit area decreased to about 50% of the normal value in the advanced cirrhosis. Fibronectin and the lectin showed the presence of sinusoids where Fc receptors were absent. The endothelium in Fc receptor-negative areas did not take up either immune complexes or carbon, and Kupffer cells were absent in these areas. A disturbed immune-complex metabolism was thus suggested to occur in association with the defect of sinusoidal Fc receptors in liver cirrhosis. These abnormalities appeared to not be directly related to perisinusoidal laminin deposition, i.e., capillarization of the sinusoid.

Pre-junctional inhibitory action of prostaglandin E2 on excitatory neuro-effector transmission in the human bronchus

The effects of prostaglandin E2 (PGE2) and indomethacin on excitatory neuro-effector transmission in the human bronchus were investigated by tension recording and microelectrode methods. PGE2 (10(-10)-10(-9)M) suppressed the amplitude of twitch contractions and excitatory junction potentials (e.j.ps) evoked by field stimulation at a steady level of basal tension obtained by the combined application of indomethacin (10(-5) M) and FPL55712 (10(-6) M). In doses over 10(-8)M, PGE2 reduced the muscle tone and dose-dependently suppressed the amplitude of twitch contractions. Indomethacin (10(-5) or 5 x 10(-5) M) reduced the muscle tone and enhanced the amplitude of twitch contractions and e.j.ps evoked by field stimulation in the presence of FPL55712. PGE2 (10(-9) M) had no effect on the post-junctional response of smooth muscle cells to exogenously applied acetylcholine (ACh) (4 x 10(-7) M). However, indomethacin (10(-5) M) significantly enhanced the ACh-induced contraction of the human bronchus. These results indicate that PGE2 in low concentrations has a pre-junctional action to inhibit excitatory neuro-effector transmission in addition to a post-junctional action, presumably by suppressing transmitter release from the vagus nerve terminals in the human bronchial tissues.

Involvement of endothelin in the regulation of human vascular tonus. Potent vasoconstrictor effect and existence in endothelial cells

Endothelin, a recently discovered endothelium-derived peptide, has been reported to produce potent vasoconstriction in various vessels of experimental animals. To study the involvement of endothelin in the regulation of vascular tonus in humans, isolated human mesenteric arteries were investigated by both pharmacological and immunohistochemical methods. The vasoconstrictor action of endothelin-1 was examined on ring segments of human mesenteric arteries. Endothelin-1 induced a slowly developing and sustained contraction, with an EC50 value (half-maximal effective concentration) of 2.9 x 10(-9) M, two orders of magnitude smaller than that of norepinephrine (EC50 of 3.9 x 10(-7) M), indicating that the vasoconstrictor action of endothelin-1 is about 100 times more potent than that of norepinephrine. The contractile effect of endothelin-1 was affected neither by adrenergic, cholinergic, histaminergic, nor serotonergic antagonists, nor by inhibitors of arachidonic acid metabolism. The vasoconstrictor response to endothelin-1 was effectively antagonized by nicardipine, a dihydropyridine Ca2+ channel blocker. Endothelin-1 profoundly augmented contractile response to Ca2+ in partially depolarized tissues. Immunohistochemical studies revealed for the first time that endothelin-like immunoreactivity was localized in endothelial cells of human mesenteric artery. The results of the present study indicate that endothelin-1 is one of the most potent vasoconstrictors in the human mesenteric artery and that it induces vasoconstriction via an ultimately accelerating Ca2+ influx through voltage-dependent Ca2+ channels. Since endothelin-1 can be located in human endothelial cells, it may play an important physiological or pathophysiological role.

Effects of acutely impaired regional function on remote myocardial wall motion and blood flow in the canine left ventricle studied by coronary occlusion and hypoxic perfusion

STUDY OBJECTIVE

The aim was to examine whether regional myocardial dysfunction has a significant effect on the wall motion and blood flow in remote non-ischaemic regions.

DESIGN

Two different severities of regional dysfunction were produced by occluding the left anterior descending coronary artery and perfusing it with a hypoxic solution. Haemodynamic variables were otherwise identical in the two conditions. The relationship of regional dysfunction in the left anterior descending artery region to regional wall motion and regional myocardial blood flow in the left circumflex artery region were examined.

EXPERIMENTAL MATERIAL

22 anaesthetised mongrel dogs, 9-16 kg, were used for the studies: 14 for the regional wall motion studies, and eight for the regional myocardial blood flow studies.

MEASUREMENTS AND MAIN RESULTS

Segment shortening in the left anterior descending artery region was impaired differently in the two conditions: arterial occlusion caused a bulge, while hypoxic perfusion caused only mild hypokinesis. Segment shortening and the myocardial blood flow in the left circumflex artery region were augmented similarly in the two conditions. Left ventricular end diastolic pressure and end diastolic segment length in the left circumflex region were increased and aortic pressure was slightly decreased by left anterior descending artery occlusion and hypoxic perfusion, but there was no significant difference between the two conditions. Heart rate was not affected.

CONCLUSION

The augmentation of wall motion and blood flow of the remote myocardium does not depend on the magnitude of acutely induced regional dysfunction per se. The augmented wall motion in the remote region is unlikely to be due to mechanical unloading of the remote myocardium due to an intraventricular regional interaction, but rather to the Frank-Starling mechanism and left ventricular afterload reduction following acute ischaemia.

Allosteric potentiation of quisqualate receptors by a nootropic drug aniracetam

1. Allosteric potentiation of the ionotropic quisqualate (iQA) receptor by a nootropic drug aniracetam (1-p-anisoyl-2-pyrrolidinone) was investigated using Xenopus oocytes injected with rat brain mRNA and rat hippocampal slices. 2. Aniracetam potentiates the iQA responses induced in Xenopus oocytes by rat brain mRNA in a reversible manner. This effect was observed above the concentrations of 0.1 mM. Kainate. N-methyl-D-aspartate and gamma-aminobutyric acid responses induced in the same oocytes were not affected. 3. The specific potentiation of iQA responses was accompanied by an increase in the conductance change of iQA and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) responses, but the affinity of receptors for agonist and the ion-selectivity of the channels (reversal potentials) were not changed. 4. Aniracetam reversibly potentiated the iQA responses recorded intracellularly from the pyramidal cells in the CA1 region of rat hippocampal slices. The excitatory postsynaptic potentials (EPSPs) in Schaffer collateral-commissural-CA1 synapses were also potentiated by aniracetam. 5. Population EPSPs recorded in the mossy fibre-CA3 synapses as well as Schaffer-commissural synapses were also potentiated by aniracetam. The amplitudes of the potentiation were not changed by the formation of long-term potentiation.

Mechanisms of stress-induced ST elevation and negative T-wave normalization studied by serial cardiokymogram in patients with a previous myocardial infarction

Seventeen patients with a previous myocardial infarction were studied during pacing to characterize the clinical correlates of ST elevation, to analyze the relation between ST elevation and negative T-wave normalization and to investigate the mechanism of these electrocardiographic changes. Myocardial ischemia was evaluated by measurement of blood lactate, and wall motion was analyzed using cardiokymographs concurrently and serially. Results show that ST elevation and negative T-wave normalization were most marked in leads containing abnormal Q waves, that ST elevation greater than or equal to 1 mm during pacing was associated with a significant increase in left ventricular end-diastolic pressure and deterioration of left ventricular wall motion and that the magnitude of ST elevation and negative T-wave normalization was significantly correlated, but the latter appeared earlier and more markedly. In addition, there was no significant correlation between the extent of either ST elevation or negative T-wave normalization and myocardial lactate production. Thus, ST elevation and negative T-wave normalization are caused by abnormal left ventricular wall motion rather than myocardial ischemia. Negative T-wave normalization is a more sensitive marker of abnormal wall motion than ST elevation in patients with a previous myocardial infarction.

Diurnal change of giant negative T wave in patients with hypertrophic cardiomyopathy

To examine the diurnal change of negative T wave (deeper than 10 mm in precordial leads) in apical hypertrophic cardiomyopathy and the mechanism of giant negative T wave, 24-h ambulatory electrocardiographic monitoring was performed in 8 patients with apical hypertrophic cardiomyopathy, and effect of atropine on electrocardiogram was studied. The mean depth of negative T wave at 1, 2, and 3 P.M. was 9.3 +/- 3.0 mm, and that at 1, 2, and 3 A.M. was 12.6 +/- 4.8 mm. The mean R-R interval at 1, 2, and 3 P.M. was 792 +/- 113 ms and that at 1, 2, and 3 A.M. was 1055 +/- 94 ms. In seven patients (88%), negative T wave was deeper during the night than during the daytime. There was a positive correlation between R-R interval and depth of negative T wave in 6 patients (75%). Despite significant shortening of R-R interval (879 +/- 116 to 804 +/- 110 ms, p less than 0.05), atropine did not significantly change the depth of negative T wave (14 +/- 5 to 14 +/- 5 mm). In conclusion, negative T wave is not fixed, but is variable, diurnally, probably due to the change of sympathetic tone.

Sequence analysis and oligonucleotide genotyping of HLA-DR"JX6", a DR"blank" haplotype found in the Japanese population

We analyzed one of the HLA-DR"blank" haplotypes found in the Japanese population using serologic studies, sequence determination, and genotyping with sequence-specific oligonucleotide (SSO) probes. The DR"blank" haplotype, designated DR"JX6", segregated in a family in association with the DRw52 and the DQw7 specificities. The cDNA and genomic DNA of the DRB1 gene originating from the DR"JX6" haplotype were amplified enzymatically and sequenced after cloning into a plasmid vector. The amino acid sequence of the first domain in the DR beta 1 chain of the DR"JX6" haplotype was different from those of other DR haplotypes sequenced so far, but in the first hypervariable region, the sequence was identical to those of the DRw11, DRw13, DRw14, and DRw17 haplotypes. SSO probes were synthesized on the basis of the DR"JX6" haplotype sequence as well as known sequences of the DRB1, DRB3, and DRB4 genes of other DR haplotypes. These SSO probes were used for the genotyping of Japanese donors whose DRB genes were amplified enzymatically and found to show a hybridization profile that was consistent with the results of serologic studies on the DR"JX6" haplotype.

Cardiac determinants of regression of left ventricular hypertrophy in essential hypertension with antihypertensive treatment

To study the cardiac determinants of regression of left ventricular hypertrophy in hypertension, left ventricular mass, fractional shortening and end-systolic wall stress were measured echocardiographically in 36 patients with essential hypertension and left ventricular hypertrophy. The patients were classified into two groups. Group I consisted of 15 patients with subnormal end-systolic wall stress, and Group II consisted of 21 patients with normal end-systolic wall stress. There were no significant differences between groups in systolic or diastolic blood pressure. After treatment for 4.4 +/- 1.7 years, echocardiographic studies were repeated. There were no significant differences between groups in the duration of the follow-up period and the kinds of antihypertensive drugs. After treatment, blood pressure decreased significantly in both groups (p less than 0.001 for both), with no significant difference between groups. Left ventricular mass increased significantly in Group I (from 331 +/- 7 to 363 +/- 24 g, mean +/- SEM, p less than 0.05), whereas it decreased significantly in Group II (from 318 +/- 16 to 268 +/- 17 g, p less than 0.001). Myocardial contractility (the relation between end-systolic wall stress and fractional shortening) remained almost the same as before treatment. In conclusion, in patients with hypertensive ventricular hypertrophy with subnormal end-systolic wall stress (inappropriate hypertrophy, probably induced by a neurohumoral factor), a decrease in blood pressure with antihypertensive treatment does not lead to regression of left ventricular hypertrophy, but rather to an increase in left ventricular mass.(ABSTRACT TRUNCATED AT 250 WORDS)

Follow-up study of the heart in acromegaly: pre- and post-operative evaluation

Pre-operative and post-operative echocardiographic data were analyzed from 8 patients with acromegaly. Pre-operatively, end-diastolic diameter was greater than 55 mm in 5 patients (63%) and concentric left ventricular hypertrophy was observed in 3 patients (38%). However, left ventricular function was normal (fractional shortening of the left ventricle greater than 28%) in all patients except 1. All patients had increased left ventricular mass. There was no significant correlation between left ventricular mass and basal plasma growth hormone concentration. An average of 23.9 months after hypophysectomy, growth hormone concentration was significantly decreased. However, the abnormal echocardiographic findings remained. In conclusion, echocardiographic abnormalities (left ventricular dilatation and hypertrophy) are common in patients with acromegaly, but systolic function is, in general, maintained. These cardiac abnormalities persist after reduction of plasma growth hormone concentration.

Two distinct subtypes of the HLA-DRw12 haplotypes in the Japanese population detected by nucleotide sequence analysis and oligonucleotide genotyping

We determined the DNA sequence of the enzymatically amplified second exon of the DRB1 gene of the Drw12 haplotypes derived from three Japanese donors and found two distinct subtypes of the DRw12 haplotype. The two subtypes, designated DRw12a and DRw12b, had single-base substitutions that predicted one amino acid change at residue number 67. The sequence of the DRw12a and DRw12b subtypes differed from those of the other DR haplotypes, but in the first hypervariable region of the DRB1 gene the sequences were identical to those of the DRw8(Dw8.1) and DRw8(Dw8.3) haplotypes. The DRw12a and DRw12b subtypes were detected in a wide range of Japanese donors by genotyping with sequence-specific oligonucleotide probes synthesized according to the DNA sequences of the two subtypes. Results of this study demonstrated that the DRw12 haplotypes in the Japanese population are genetically diverse, as many other DR haplotypes are.

Alterations in Fc receptor activity in sinusoidal endothelial cells and Kupffer cells during D-galactosamine (GalN)-induced liver injury in rats. A histological study

Fc receptors in sinusoidal cells and immune complex uptake were studied histologically in D-galactosamine HCl (GalN)-induced liver injury in rats. Kupffer cells and monocytes were distinguished from sinusoidal endothelial cells and from each other by endogenous peroxidase staining. Fc receptors were found along the sinusoidal endothelium throughout the lobules in normal livers. In acute injury caused by 300 or 750 mg/kg of GalN, Fc receptors were preserved within necrotic foci until the foci were infiltrated by inflammatory cells. The endothelial Fc receptor activity altered, as demonstrated by their capacity to bind immune complexes, after GalN injection. The activity decreased from 24 h after injection in the periportal areas in both dose groups, and increased transiently with dose-dependence in the remaining areas. Kupffer cell numbers also showed a transient dose-dependent increase, except in the periphery of lobules where they generally decreased. In chronic injury with 400 mg/kg, Fc receptors were lost and Kupffer cells decreased in the periportal areas. Circulating immune complexes were ingested by Kupffer cells and endothelial cells in normal and injured livers, showing the the same distribution as that of Fc receptors except that the complexes decreased gradually towards the centrilobular zones.