[Current treatment concepts in patients in the acute stage of subarachnoid hemorrhage due to rupture of an intracranial aneurysm]

Subarachnoid hemorrhage (SAH) due to rupture of intracranial aneurysm constitutes almost 10% of all strokes and is a neurosurgical emergency along with head injury and intracerebral hemorrhage. Accurate diagnosis and surgical intervention without time loss are the key factors for successful treatment. Almost 40% of the patients with SAH already die or are in a moribund status at the first bleeding before hospitalization, the rest of the patients (60%) can be transferred to hospitals for further treatment. The factors determining prognosis of SAH involve a direct initial injury to the brain at the time of the rupture, a high rebleeding rate in the acute stage, development of cerebral vasospasms, and hydrocephalus due to stasis of the cerebrospinal fluid. Surgical intervention is intended to eliminate these factors as much as possible. Perioperative intensive medical care in combination with the surgical intervention is essential to achieve best outcome from the surgical treatment. The aim of this article is to make a short review over SAH and to give a current concept of therapy in the acute stage of SAH. The results of treatment of SAH in our institute are also presented and discussed.

Prolonged hyperalimentation as a possible cause of renal tubular dysfunction: evaluation of 1,5-anhydro-D-glucitol resorption and N-acetylglucosaminidase excretion in humans

1. A major polyol found in the sera and other tissues of humans, 1,5-anhydro-D-glucitol, is mainly ingested in the diet and is excreted in urine. We compared the influence of the long-term administration of total parenteral nutrition free of 1,5-anhydro-D-glucitol with that of total enteral nutrition on the serum level of 1,5-anhydro-D-glucitol in 46 patients who could not take food by mouth. 2. The serum concentration of 1,5-anhydro-D-glucitol and its kinetics remained unchanged in the group receiving total enteral nutrition (n = 21) over a period of 12 months. However, after 1 month on total parenteral nutrition (n = 25), the serum level of 1,5-anhydro-D-glucitol decreased, falling to about one-sixth the pretreatment level in the 12th month. Because the serum level of 1,5-anhydro-D-glucitol continued to decline, falling below the limit at which its renal reabsorption is normally activated, this decrease did not seem to be caused directly by a nutritional deficiency of this substance. 3. The urinary excretion of 1,5-anhydro-D-glucitol was closely correlated (r = 0.792) with that of N-acetyl-beta-glucosaminidase; but not with the serum creatinine level or of the urinary excretion of microalbumin or of urinary beta 2-microglobulin. We observed no glucosuria, hyperuricuria or changes in serum electrolytes during total parenteral nutrition. 4. The reduction in the serum level of 1,5-anhydro-D-glucitol and the urinary excretion of N-acetyl-beta-glucosaminidase were correlated with the duration of total parenteral nutrition administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of MPL 9000 extracorporeal shock wave lithotripsy on renal hemodynamics and urine flow: assessment by 99mTc-DTPA renal scintigraphy

The effect of extracorporeal shock wave lithotripsy (ESWL) with an MPL9000 lithotriptor on renal hemodynamics and urine flow was investigated by 99mTc-DTPA renal scintigraphy. In the first-pass scintigrams obtained within 1 min after injection of 99mTc-DTPA, there was no significant change in the time to the maximum radioactivity level and the maximum radioactivity ratio at 1 day before ESWL and 1 day or 1 month after ESWL. However, analysis of 30-min scintigrams showed that urinary clearance of radioactivity was delayed in the treated kidney 1 day after ESWL, particularly in the region targeted by shock waves, despite the absence of overt urinary tract obstruction by residual stone fragments. This change was reversible and was no longer noted 1 month after ESWL. These results suggest that ESWL with the MPL9000 lithotriptor induces a focal and temporary decrease in urine flow in the treated kidney, but has little or no effect on renal hemodynamics.

Postadsorptive behavior of plasma proteins on poly(propylene oxide)-segmented nylon-610 surfaces and its implication in preventing contact-induced activation of platelets on these surfaces

The influence of adsorbed plasma proteins on preventing contact-induced activation of platelets on poly(propylene oxide) (PPO)-segmented nylon-610 surfaces was investigated by monitoring changes in cytoplasmic free Ca2+ concentrations in platelets and adsorption/desorption of albumin and fibrinogen on these copolymer surfaces. Direct measurement of cytoplasmic free Ca2+ concentration in platelets in contact with copolymer surfaces was achieved by monitoring spectral changes of a fluorescent indicator dye, Fura 2. These copolymers were characterized by a surface microstructure composed of coexisting crystalline and amorphous phases. An increase in cytoplasmic free Ca2+ concentration in platelets interacting with polymer surfaces was observed, and this increase was found to be strongly reduced both by the adsorption of plasma proteins into the polymer surface and by modifying the surface microstructure of the polymer itself. Transient changes in cytoplasmic free Ca2+ concentration were observed in platelets in contact with the surface of copolymer 61P3-25, which exhibited excellent nonthrombogenicity in our previous studies, depending on the residence time of plasma and plasma concentration. Additionally, adsorption/desorption of albumin and fibrinogen on copolymer surfaces was estimated using 125I-labeled proteins. Exchange of the adsorbed albumin with fibrinogen and minimum fibrinogen adsorption were observed particularly on the 61P3-25 surface. Exchange of adsorbed fibrinogen with plasma proteins and/or increased fibrinogen adsorption were also observed on all other polymer surfaces examined. Finally, we conclude that controlled formation of a defined protein adsorption layer on the 61P3-25 surface via the transient exchange of adsorbed albumin with fibrinogen from plasma, can be a dominant factor in preventing platelet adhesion and activation on this surface.

Temperature-responsive bioconjugates. 3. Antibody-poly (N-isopropylacrylamide) conjugates for temperature-modulated precipitations and affinity bioseparations

Immunoglobulin G (IgG) has been modified by poly(N-isopropylacrylamide) (PIPAAm) to create a novel bioconjugate which exhibits reversible phase transition behavior at 32 degrees C in aqueous media. A terminal carboxyl group introduced into PIPAAm molecule by polymerization of IPAAm with 3-mercaptopropionic acid was used for conjugation to IgG via coupling reaction of activated ester with protein amino group. These conjugates exhibited rapid response to changes in solution temperature and significant phase separation above a critical solution temperature corresponding to that for the original PIPAAm. These conjugates bound to antigen quantitatively in aqueous system, and antigen-bound complex also demonstrated phase separation and precipitation above a critical temperature. Precipitate was reversibly redissolved in cold buffer. Though particular conjugate which includes 12 molecules of PIPAAm with 6,100 molecular weight suppressed more than 95% of Fc-dependent binding with protein A, it retained approximately 60% of original specific antigen binding activity. It was manifested that polymer content of conjugate was 20-30 wt% for the case of 6,100 molecular weight of PIPAAm to demonstrate specific antigen binding activity most effectively and to reduce Fc-dependent binding with protein A. IgG-PIPAAm conjugates were soluble in water and formed antigen-bound complex in homogeneous solution system below a critical temperature. These conjugates were separated from solution and other solutes corresponding to PIPAAm nature and scarcely bound to antigen above a critical temperature. It is revealed that temperature-responsive PIPAAm conjugated to biomolecule operated as a switching molecule. These phenomena are attractive for not only reversible bioreactors and protein separations but also carrier substrate to localize biomolecules such as drugs, peptides and hormones in a living body.

Clinical significance of urinary enzymes and beta 2-microglobulin following ESWL

To examine the renal damage caused by shock waves, urinary excretion of enzymes and beta 2-microglobulin were determined before and after ESWL. Urine samples were obtained from 35 patients with renal stone and 26 patients with ureteric stone treated with ESWL. Urinary lactate dehydrogenase (LDH) levels significantly increased on day 0, just after ESWL, in both groups. In the ureteric stone group the kidneys received less shock waves than in the renal stone group. Increased urinary lactate dehydrogenase was considered to have derived from erythrocytes in urine. Elevated urinary N-acetyl-beta-D-glucosaminidase (NAG) levels were also observed on day 0 after ESWL in both groups, due to unknown reasons. Indirect effect of ESWL through the sympathetic nervous system or humoral factors may contribute to increases in the urinary excretion of NAG. No significant increase was found in urinary gamma-glutamyl-transpeptidase (GGTP) levels for 5 days after ESWL. Urinary beta 2-microglobulin (BMG) levels increased on day 0 in the renal stone group alone. In our present study, the clinical significance of urinary enzymes and BMG was not well evaluated, because urinary excretion of these indicators following ESWL were transient and mild.

[Immunohistological study in Bruch's membrane of senescence accelerated mouse]

Age-related macular degeneration is one of the major causes of severe visual loss is elderly individuals. However, relatively little is known about its etiology. The disease may be associated with senescence. Ultrastructural and immunohistochemical studies on SAM (senescence accelerated mouse) eyes were carried out to learn details of aging changes in the retinal pigment epithelium (RPE) and Bruch's membrane. SAM P 1 mice aged 2, 10, 14 months were examined in this study. The eyes were analysed for type IV collagen and heparan sulfate proteoglycan (HSPG) by the avidin-biotin-peroxidase complexes (ABC) method and post-embeddig immunolocalization with colloidal gold. With the ABC method, the basement membranes of both the RPE and the choriocapillaris showed markedly positive staining when treated with anti-type IV collagen antibody and moderately positive staining when treated with anti-HSPG antibody. In ultrastructural immunolocalization, both basement membranes showed fairly heavy labeling in response to the antibodies to type IV collagen, and moderate labeling in response to the antibodies to HSPG. With aging, the thickness of the basement membrane of the choriocapillaris and gold particle labeling by the antibodies to type IV collagen increased. The gold particle labeling by the antibodies to HSPG increased slightly, but was distributed sparsely. These results showed the advancing process of senescence changes in Bruch's membrane.

Temperature modulated solubility-activity alterations for poly(N-isopropylacrylamide)-lipase conjugates

Chemical modification of proteins by use of functional polymers is expected to endow them with new properties without destroying their native functions, thus providing useful materials for application in different fields. We have synthesized poly(N-isopropylacrylamide) [poly(IPAAm)] co-oligomer with N,N-dimethylacrylamide (DMAAm) and reactive end groups by telomerization of IPAAm. This co-oligomer exhibits a lower critical solution temperature (LCST) at 37 degrees C. Using this temperature-responsive semitelechelic co-oligomer, we prepared polymer-enzyme conjugates of lipase by covalent coupling via carboxyl end-groups. This bioconjugate exhibits a LCST at 37 degrees C, having rapid, reversible hydration-dehydration changes due to highly mobile free polymer end groups. The conjugate retained its native enzymatic activity below this critical temperature, above which it precipitated and its catalytic function was shut off. This conjugate can be readily separated from reaction mixtures as a precipitate by simple temperature changes after reaction and reused in cycles without denaturation. Such a modulated system is attractive for application as a novel bioreactor system.

[Proteoglycan in Bruch's membrane of senescence accelerated mouse: localization and age-related changes]

We demonstrated the distribution of sulfated proteoglycans in Bruch's membrane of Senescence Accelerated Mouse histochemically and ultrastructurally using cuprolinic blue in conjunction with specific enzyme treatments and nitrous acid digestion. Two kinds of proteoglycan filaments were observed in the inner and outer collagenous layers, i.e., small collagen fibril-associated filaments (11 nm in average length), and large filaments (32 nm in average length). Intermediate size filaments (25 nm in average length) were seen in the basement membranes of the retinal pigment epithelium and choriocapillaris. Chondroitinase AC treatment eliminated the staining of filaments in the collagenous layers (chondroitin sulfate). Chondroitinase ABC treatment also eliminated the staining of filaments in the collagenous layers (chondroitin sulfate and dermatan sulfate). Nitrous acid eliminated the staining of filaments in both basement membranes (heparan sulfate). Proteoglycans containing chondroitin sulfate and dermatan sulfate were associated uniquely with collagen fibrils. Heparan sulfate proteoglycans were associated with the basement membranes of the pigment epithelium and choriocapillaris. With aging, the thickness of the basement membrane of the choriocapillaris and the staining of the filaments in the basement membranes of the pigment epithelium and choriocapillaris (heparan sulfate proteoglycans) increased. Collagen fibers became disarranged and the staining of both filaments in the collagenous layers decreased. The results of the staining characteristics probably reflect the aging of Bruch's membrane.

Effect of nerve growth factor on delayed neuronal death after cerebral ischaemia

We investigated the protective action of nerve growth factor (NGF) on delayed neuronal death, and we also studied the involvement of the 200 kDa neurofilament (NF200) cytoskeletal proteins. Wistar rats were divided into three groups: Group I, in which transient forebrain ischaemia was produced; Group II, ischaemic group which received intraventricular administration of artificial cerebrospinal fluid (CSF); and Group III, ischaemic group which received intraventricular administration of 2 micrograms of 2.5 S NGF. Forebrain ischaemia in these rats was produced by causing transient bilateral occlusion of the common carotid arteries and lowering the mean blood pressure to 50 mmHg for 8 minutes. On the 1st and 7th day after ischaemia we histologically examined neuronal death in the hippocampal CA 1 sector. On the 7th day after ischaemia, mean cell death (degenerative cell number/total cell number) was 87 +/- 9% in group I (n = 7), 51 +/- 36% in group II (n = 7), and 14 +/- 16% in group III (n = 8) (p < 0.05 vs. group II). The concentration of NF200 in the hippocampal homogenate was measured by the Western blotting method on the 1st and 7th day after ischaemia. On the 1st day it was found to be 67 +/- 11% of that in the control group in group I (n = 6), 73 +/- 21% in group II (n = 6), and 84 +/- 7% in group III (n = 6) (p < 0.05 vs. group II). The concentration of NF200 in all groups remained at the same level until the 7th day after ischaemia (each group, n = 6).(ABSTRACT TRUNCATED AT 250 WORDS)

Alteration of in vivo cytokine gene expression in mice infected with a molecular clone of the defective MAIDS virus

The discovery of T helper type 1 (Th1) and T helper type 2 (Th2) phenotypes within the CD4+ T-lymphocyte population has allowed for further elucidation of the roles the T cells play in regulation of humoral and cellular immunity. It is suggested that differential activation of the CD4+ subsets, particularly up-regulation of the Th2 cell and down-regulation of the Th1 cell, may be associated with diseases as diverse as AIDS and asthma. We report herein that by using the polymerase chain reaction to analyze the kinetics of in vivo cytokine- and virus-specific gene expression, we can show that mice infected with the molecularly cloned MAIDS defective virus 1/27/A BM5 exhibit an alteration in cytokine gene expression that closely parallels an increase in spleen cell numbers, an increase in IgM production, a decrease in the stimulation index, and an increase in defective-virus gene expression in these mice. As has been suggested to be true for human AIDS, the observed alteration of cytokine gene expression suggests that a pattern of expression similar to that produced by Th2 cells may also have a role in the development of MAIDS.

Heterogeneous eosinophils of allergic rhinitis in chemotactic response

Chemotactic responses of eosinophils from patients with allergic rhinitis to 5 STO-2-derived eosinophil chemotactic factors (ECF), IL-3, IL-5 and GM-CSF were examined. The patients were divided into two groups: patients with perennial allergic rhinitis sensitive to Dermatophagoides farinae and those with seasonal allergic rhinitis sensitive to Japanese cedar pollen. There was no essential difference between chemotactic response of eosinophils from the former to STO-2-derived ECF and that from healthy individuals. However, eosinophils from patients with seasonal allergic rhinitis failed to respond to one of the STO-2-derived ECFs, ECF-P19. Before and after nasal antigen provocation, no change occurred in the chemotactic profiles. Furthermore, we found that eosinophils from both types of patients with allergic rhinitis responded not only to IL-3 and GM-CSF but also to IL-5 unlike those of healthy individuals.

Suppression of intestinal smooth muscle contraction by 4-ethylguaiacol, a constituent of wood creosote

Wood creosote, a mixture of phenolic compounds, suppresses in vitro contractions of rat intestine. To identify a compound in wood creosote able to inhibit intestinal motility, we screened its constituent phenolic compounds and found 4-ethylguaiacol (4-EG) as an active compound. It suppressed the spontaneous phasic (IC50 = 513 +/- 48 mumol/l) as well as spasmogenic-agent-induced tonic longitudinal contractions of isolated rat ileum in a reversible and concentration-dependent manner. KCl-depolarization-induced tonic contraction, which was susceptible to a calcium channel blocking agent, was also suppressed by 4-EG with an IC50 of 433 +/- 41 mumol/l. Furthermore, calcium-ionophore-induced contraction, which was affected by an influx of extracellular calcium ion that bypassed calcium channels, was suppressed by 4-EG with an IC50 of 97 +/- 18 mumol/l. These results support the concept that the effect of wood creosote to suppress intestinal motility is attributable, partially or entirely, to its component 4-EG and that this effect of 4-EG on the intestinal muscle is produced at some stage(s) of the muscle contraction process after influx of extracellular calcium into the cytosol of smooth muscle.

Temperature-responsive bioconjugates. 2. Molecular design for temperature-modulated bioseparations

We have synthesized carboxyl semitelechelic oligo(N-isopropylacrylamide) (OIPAAm) using radical telomerization with 3-mercaptopropionic acid. This telomerization is also effective for the synthesis of carboxyl semitelechelic co-oligomers of IPAAm with butyl methacrylate (BMA) as hydrophobic or N,N-dimethylacrylamide (DMAAm) as hydrophilic comonomers. All co-oligomers are highly water-soluble at lower temperatures and exhibit phase separation with increasing temperature. Pure OIPAAm exhibits a lower critical solution temperature (LCST) at 32 degrees C, and the LCST for co-oligomers can be controlled to increase over 32 degrees C with increasing DMAAm composition and to decrease below 32 degrees C with increasing BMA composition. OIPAAm was grafted to bovine serum albumin (BSA) and bovine plasma fibrinogen (BPF) by activated ester-amine coupling. These OIPAAm-biomolecule conjugates maintain their temperature responses, are soluble in cold water, and precipitate over a range of temperatures related to oligomer content. Conjugates could be selectively precipitated and independently separated from conjugate solution mixtures with increasing temperature. In this case, the number of OIPAAm molecules attached to a conjugate affects the aggregate sizes of precipitated conjugates in mixtures. Both conjugate mixture ratios and solution concentrations influence the contamination of oligo(IPAAm-co-DMAAm)-BSA conjugates in precipitated oligo(IPAAm-co-BMA)-BPF conjugates. Furthermore, precipitated conjugates separated using centrifugation and filtration redissolve in water and maintain their biofunctionality, indicating the potential of strategy in reversible bioreactors and protein separations.

Differential inhibition of a transient K+ current by chlorpromazine and 4-aminopyridine in neurones of the rat dorsal root ganglia

1. K+ currents were recorded from neurones of the newborn rat cultured dorsal root ganglia, by a whole cell variation of the patch-clamp technique. 2. Chlorpromazine (CPZ), a neuroleptic, reversibly reduced the amplitude of the transient K+ current (referred to as 'IT' hereafter) with a dissociation constant (Kd) of 4.5 microM. The inhibition of the delayed rectifier K+ current (IDR) was much less potent (Kd, 120 microM). CPZ (100 microM) had no effect on the inward rectifier K+ current. 3. The blocking action of CPZ on IT was about seven times more potent than that of 4-aminopyridine (4-AP) which had a Kd of 31 microM. The inhibition of IT followed one-to-one binding stoichiometry with both drugs. 4. The decay time course of IT was not affected by CPZ, whereas 4-AP markedly accelerated the decay phase of IT. 5. The steady-state inactivation curve of IT was shifted in the negative direction (about 5 mV) by CPZ, whereas the curve was shifted in the positive direction (about 13 mV) by 4-AP. 6. The recovery from inactivation as measured by a conventional double pulse protocol was described by two exponential components in the control solution. CPZ markedly reduced the first component and slowed down the recovery from inactivation. In contrast, in the presence of 4-AP, the peak amplitude of IT was rather increased by a preceding IT possibly through voltage-dependent unbinding of 4-AP molecules. 7. These results indicate that CPZ has a preferential blocking action on IT and the mechanism underlying this block is markedly different from the mechanism underlying the blocking action of 4-AP.

Kinetic analysis of two types of Na+ channels in rat dorsal root ganglia

1. The gating properties of two types of Na+ channels were studied in neurones isolated from rat dorsal root ganglia using the whole cell variation of the patch electrode voltage-clamp technique. 2. Two types of Na+ currents (INa) were identified on the basis of their sensitivity to tetrodotoxin (TTX). One type was insensitive to TTX (up to 0.1 mM), while the other type was blocked by 1 nM of TTX. Whereas they were both insensitive to 50 microM Cd2+, a high concentration (2 mM) of Co2+ selectively inhibited the TTX-insensitive type. 3. The activation thresholds were about -60 and -40 mV for the TTX-sensitive and the TTX-insensitive INa, respectively. Activation of the TTX-sensitive INa developed with a sigmoidal time course which was described by m3 kinetics, whereas the activation of the TTX-insensitive INa was described by a single exponential function. A deactivation process, as measured by the tail current upon repolarization, followed an exponential decay in either type of INa. 4. The rate constant of activation indicated that under comparable membrane potential conditions, the TTX-insensitive channels open 4-5 times slower than the TTX-sensitive ones upon depolarization. Likewise, the rate constant of inactivation indicated that the TTX-insensitive channels inactivate 3-7 times more slowly than the TTX-sensitive ones upon repolarization. 5. The steady-state activation curve for the TTX-insensitive INa was shifted about 20 mV in the positive direction from that for the TTX-sensitive INa. 6. The steady-state inactivation curve for the TTX-insensitive INa as obtained with a 0.5 s prepulse was shifted about 26 mV in the positive direction from that for the TTX-sensitive INa, indicating a greater availability for the TTX-insensitive INa in depolarized membrane. However, on increasing the duration of prepulse, the inactivation curve for the TTX-insensitive INa, but not for the TTX-sensitive INa, shifted in the negative direction due to an extremely slow inactivation process in the TTX-insensitive INa. Consequently, an overlap between the activation and inactivation curves which causes a steady influx of Na+ (window current) became progressively reduce. 7. The time course of INa decay was best described by a single exponential process in either the TTX-sensitive or TTX-insensitive INa, whereas the development of inactivation and the recovery from inactivation, which were measured by a conventional double-pulse protocol, followed a second order process in either channel type.(ABSTRACT TRUNCATED AT 400 WORDS)

[Idiopathic normal pressure hydrocephalus in elderly patients: its pathophysiology and diagnosis]

We described 10 cases of idiopathic normal pressure hydrocephalus (NPH) in elderly patients who had good results after shunting. Retrospective analysis of our cases offers the following results which indicate the pathogenesis and surgical selection of idiopathic NPH. 1) Most of the patients had risk factors of ischemic cerebrovascular disease and had multiple small ischemic lesions such as lacunae. 2) Cerebrospinal fluid (CSF) pressure is below 20mmHg in all cases and its response to acetazolamide loading was suppressed or almost lost in most of cases. 3) The volume of the lateral ventricle was slightly reduced after the effective operation. 4) Some of the patients showed clinical improvement even if they had symptoms for more than 2 years before treatment. Two primary theories exist concerning the cause of NPH. One is extraventricular obstruction to CSF flow at the level of the arachnoid villi or the basal cistern. The other is periventricular white matter ischemic damage which decreases the tensile strength of the ventricular walls and leads to ventricular dilatation. Tangential periventricular shearing force due to ventricular dilatation produces the symptom of NPH. Our results support these descriptions as the causes of idiopathic NPH in elderly patients. We noticed, firstly, involvement of the ischemic risk factor. Other findings implied decreased elasticity or compliance of the brain and the loss of the autoregulatory properties of cerebral circulation which accelerate the ischemic damage to the periventricular white matter. In understanding the etiology, it is important to know the fragility of the aged brain and the mechanical and hemodynamic stress to which it is subjected.(ABSTRACT TRUNCATED AT 250 WORDS)

Alterations of a 200 kDa neurofilament in the rat hippocampus after forebrain ischemia

Alteration in the concentration of a 200 kDa neurofilament (NF200) in the rat hippocampus after forebrain ischemia and its relationship to hippocampal neuronal death were studied with an anti-200 kDa neurofilament antibody, using immunohistochemical and immunoblotting techniques. In rats subjected to 8 min of transient forebrain ischemia, hematoxylin-eosin staining showed survival of most of the neurons in the hippocampal CA1 region at 1 day and loss of more than 75% of the neurons at 7 days after ischemia. Immunoblotting showed that the concentration of NF200 in the hippocampal homogenate tended to decrease after ischemia, to 69% of that of control at 1 day and to 60% of the control value at 7 days after 8 min of forebrain ischemia. Following 5 min of ischemia as well, the decrease in the concentration of neurofilaments in the hippocampal region preceded histological confirmation of neuronal cell death. These results suggest that degradation of neurofilament triplet proteins occurred even after ischemia of minimal duration and preceded neuronal death. Degradation of cytoskeletal proteins may play an important role in the mechanism of delayed neuronal death after cerebral ischemia.

The complete nucleotide sequence of a pre-core mutant of hepatitis B virus implicated in fulminant hepatitis and its biological characterization in chimpanzees

Hepatitis B virus (HBV) with an in-frame stop codon within the pre-core region of the virus genome caused fulminant hepatitis in two individuals. Serum from a chronically infected patient who was the source of the virus was inoculated into three chimpanzees at dilutions of 10(-1), 10(-3), and 10(-7). All three chimpanzees developed acute hepatitis B with relatively high peak values of liver enzymes in their serum. The complete nucleotide sequence of virus DNA recovered from the chimpanzee serum by enzymatic amplification was identical with that from the human serum. By comparing the sequence of this strain (HT) with that of 32 published HBV genomes, changes in nucleotides and predicted amino acids that were rarely or never found in other HBV isolates were identified. Thirteen such nucleotides were found within the cis-acting regulatory elements, of which 6 were within the enhancer II-core promoter region. Twenty-four rare or unique changes in amino acids were found in open reading frames, of which 15 occurred in the region that spanned the 3' half of the X gene, through the pre-core/core gene, to the 5' end of the polymerase gene. Thus, an HBV pre-core stop mutant implicated in fulminant hepatitis is highly infectious, induces severe hepatitis in chimpanzees, and possesses significant genetic variation from reported HBV isolates.

[Age-related changes in Bruch's membrane of the senescence accelerated mouse]

We studied pathological changes in Bruch's membrane of Senescence Accelerated Mouse (SAM) P/1. Tannic acid was used to demonstrate collagen fibers and microfibrils in Bruch's membrane. With aging, thickening of Bruch's membrane, especially thickening of the basement membrane of the choriocapillaris, was remarkable. The distance between collagen fibers also became wider, and many more fine fibrils appeared around each collagen fibril with aging. These changes were observed mor in the posterior area than in the periphery.

[Clinical experiences in using ITC silastic detachable balloons--report on 30 cases with various neurovascular diseases]

As defective balloons often lead to disasters, reliable detachable balloons have long been eagerly awaited. We had the opportunity of using ITC detachable balloons on 30 cases with various neurovascular diseases. No defective balloon was found during in vitro testing done immediately prior to their placement in the patient's vascular system. Moreover, there was no premature detachment during catheter manipulation or early deflation within several weeks after detachment. Both immediate and long term follow up showed balloon embolization would be the first choice for various direct arteriovenous fistulae. Also, anatomically inaccessible aneurysms with small necks, less than 1 cc in volume, could be successfully treated by detachable balloons. However, detachable balloons are not ideal embolic material for large and giant aneurysms. In conclusion, when used by properly trained personnel, ITC silastic detachable balloons are a safe, easy to use and reliable option.

Markedly prolonged incubation period of hepatitis B in a chimpanzee passively immunized with a human monoclonal antibody to the a determinant of hepatitis B surface antigen

The protective efficacy of a human monoclonal antibody directed against the a determinant of hepatitis B virus (HBV) surface antigen was studied in a chimpanzee. A single high dose of 5 mg/kg (body weight) of monoclonal antibody SDZ OST 577 was intravenously administered to a chimpanzee, followed by intravenous challenge with 10(3.5) chimpanzee infectious doses of a wild-type HBV, the MS-2 strain (ayw subtype). The passively acquired antibody to HBV surface antigen could be detected for 40 weeks. Serum HBV DNA tested by a "nested" polymerase chain reaction assay was negative through the 36th week after virus challenge but became positive by the 38th week. The chimpanzee subsequently developed acute hepatitis B approximately 1 year after challenge. The nucleotide sequence of the a determinant of the surface gene of the replicated virus was identical with that of the inoculated wild-type virus. Thus, a human monoclonal antibody directed against the a determinant of HBV surface antigen delayed but did not prevent experimental infection of HBV and hepatitis in the chimpanzee. Our results indicate an incomplete ability of this antibody to protect against HBV infection in vivo after a single infusion.

Differential inhibition of transient and long-lasting calcium channel currents by benzodiazepines in neuroblastoma cells

The effects of diazepam, nitrazepam, clonazepam, and Ro5-4864 on transient (type I) and long-lasting (type II) calcium channels associated with low-affinity benzodiazepine receptors were investigated using the whole-cell patch-clamp technique. Clonazepam (100 microM), a specific agonist for the central-type benzodiazepine receptor, reduced transient currents through the type I calcium channel by 40% without affecting long-lasting currents through the type II calcium channel. Diazepam and nitrazepam (100 microM), non-specific agonists for both the central- and peripheral-type benzodiazepine receptors, reduced both transient and long-lasting currents equally by 25-30%. A similar non-selective inhibition was observed by Ro5-4864 (1-10 microM), a specific agonist for the peripheral-type benzodiazepine receptor. It is concluded that the two calcium channel types are regulated differentially by two different kinds of benzodiazepines; central-type for type I channel and peripheral-type for both type I and type II channels.

Beta-D-glucan concentrations detected by Toxicolor and Endospecy tests in the urine of patients with urinary fungal infections

Beta-D-glucan is an essential component of the cell wall of fungi. We measured its concentration in the urine of patients with funguria using the chromogenic endotoxin assay kits, Toxicolor and Endospecy. These assay systems use the same Limulus coagulation enzymes. Since the Endospecy test detects endotoxin but not factor G, which is activated by beta-D-glucan, the beta-D-glucan concentration can be calculated by subtracting the Endospecy value from the Toxicolor value. Concentrations of beta-D-glucan were found to be significantly higher in urine samples from patients with funguria (> or = 10(3) colony-forming units/ml) than in non-infected samples.

Direct inactivation of human polymorphonuclear leukocyte by hyperosmotic urea comparable to the renal medulla

Hyperosmolarity in the renal medulla inhibits host defenses against bacterial pyelonephritis. Urea and NaCl contribute most to high osmolarity in the renal medulla. We therefore examined the inhibitory mechanism of urea on superoxide generation by human polymorphonuclear leukocytes. Superoxide production was inhibited by high concentration of urea. This inhibition was found to be direct and immediate. In addition, direct inactivation of NADPH oxidase, the key enzyme complex of superoxide generation, was shown by an NADPH oxidase activity assay using cell lysates of polymorphonuclear leukocytes stimulated by phorbol myristate acetate. The inhibitory effect of urea on NADPH oxidase was reversed by washing urea out of the assay system of cell lysates. Kinetic analysis of the inhibition of NADPH oxidase activity by urea showed decreased Vmax and Km, suggesting uncompetitive inhibition. These findings suggested that urea inactivated polymorphonuclear leukocyte superoxide production through a direct and uncompetitive inhibition of NADPH oxidase.

Temperature-responsive bioconjugates. 1. Synthesis of temperature-responsive oligomers with reactive end groups and their coupling to biomolecules

Using 3-mercaptopropionic acid (MPA) as a chain-transfer agent, the radical oligomerization of N-isopropylacrylamie (IPAAm) was carried out with varying molar ratios of MPA to IPAAm and DMF. The molecular weight of oligo-IPAAm (OIPAAm) could be controlled by the ratio of MPA to IPAAm. The OIPAAm was confirmed to average one carboxyl end group per chain. All OIPAAms samples were highly water-soluble at lower temperatures and exhibited phase separation near 32 degrees C. The optical transmittance of the OIPAAms aqueous solutions changed drastically at 32 degrees C which was independent of OIPAAms molecular weight. In aqueous solutions of OIPAAm having concentrations higher than 1 wt% and molecular weight of 6100, the oligomers were precipitated and recovered in 85 wt% yield of their original content. Further, OIPAAm was grafted to atelo collagen by activated ester-amine coupling. The OIPAAm-collagen conjugates were able to dissolved in cold water and precipitated at 34 degrees C. Temperature-responsive OIPAAm-collagen conjugates are expected to maintain native collagen functionality in the solution state, react at lower temperatures, and be easily removed from the system with small temperature increases.

Effect of prednisolone on renal scarring in rats following infection with Serratia marcescens

Renal scarring is considered a criterion of reflux nephropathy and the end stage of pyelonephritis. Prednisolone, a strong anti-inflammatory drug, at doses of 1 or 2 mg/kg prevented renal scarring in rats following infection with Serratia marcescens. Four or 8 mg/kg of prednisolone, however, did not inhibit renal scar formation. In a time course experiment, renal scarring was prevented when 4-day treatment with prednisolone was initiated 2, 5, or 13 days after infection. These results show that prednisolone is effective in preventing such scarring and suggest the clinical use of this drug for preventing renal scar formation after pyelonephritis and reflux nephropathy.

Demonstration of antidiarrheal and antimotility effects of wood creosote

Wood creosote administered to rats prevented castor-oil-induced diarrhea with an ED50 of 53 mg/kg p.o. This antidiarrheal effect was apparently produced by acceleration of net fluid absorption from the intestine, as shown by a 52% decrease (p < 0.001) of residual fluid volume in an intestinal loop, and partly by suppression of intestinal motility. Wood creosote also inhibited spontaneous longitudinal contractions of isolated ileal segments in rats (IC50 = 28 mg/l) and guinea pigs (IC50 = 17 mg/l). Contractions of the guinea pig ileum induced by electrical stimulation, bradykinin and acetylcholine were also inhibited dose-dependently. We conclude that wood creosote has an antidiarrheal activity and that this effect is exerted by inhibition of intestinal motility and by augmentation of net fluid absorption from the intestine.

Enhancement of superoxide production of polymorphonuclear neutrophils by ofloxacin and the effects of the inhibitors of protein kinase C

Polymorphonuclear neutrophils (PMN) represent an important defense mechanism against bacterial infection. Superoxide is one of the most important factors released by PMN following various stimulations including bacteria. Augmentation of chemiluminescence response of PMN stimulated by phorbol myristate acetate was observed following the addition of 25-200 micrograms/ml of ofloxacin, a new quinolone antimicrobial agent. In addition, the effects of two inhibitors of protein kinase C, staurosporine and H-7, were examined. The augmented superoxide production was inhibited by 1 or 2 microM of staurosporine or 50 or 100 microM of H-7. These results suggest that ofloxacin augments superoxide production of PMN and that this augmentation is probably due to the enhancement of leukocyte protein kinase C.

Regeneration of the rat carotid artery after clipping injury. Part II. A pharmacological study

This study investigated the natural course of functional recovery of the vascular endothelium and smooth muscle after clipping injury of the rat carotid artery. Vascular injury was induced by clipping the right carotid arteries of Wistar rats. The contractile response to KCl, serotonin (5-hydroxytryptamine), and norepinephrine was decreased immediately after arterial injury. The response to KCl and serotonin recovered within 8 weeks, whereas the response to norepinephrine recovered after 12 weeks. Endothelium-dependent relaxation also disappeared immediately after clipping injury, but the recovery of relaxation in response to acetylcholine and adenosine triphosphate was observed within 1 week. Four weeks after clipping injury, higher doses of acetylcholine induced slight arterial contraction. These findings suggest that the recovery of smooth muscle contractility was slower than the process of endothelial regeneration in the rat carotid artery after clipping injury. Endothelium-dependent relaxation recovered within only a week, although the characteristics of the arterial cholinergic receptors may have changed in the chronic recovery stage.

Pulse methylprednisolone therapy in the treatment of Wegener's granulomatosis

Five patients with Wegener's granulomatosis were treated with high-dose intravenous methylprednisolone (MTP) pulse therapy. Three out of five patients received MTP pulse therapy as the initial treatment and remission was achieved. Renal biopsy after the treatment confirmed the improvement of kidney involvement in 2 cases. Although the other two patients received MTP pulse therapy when a relapse occurred, the therapy could not suppress the progression of the disease. These observations suggest that MTP pulse therapy when given early may make it possible to suppress the progression of kidney involvement and improve the prognosis of the disease. Furthermore, it may also decrease the total doses of oral steroids and cyclophosphamide because of a strong anti-inflammatory and immunosuppressive action and consequently diminish the side effects. In conclusion MTP pulse therapy as the initial treatment may be beneficial in treating patients with Wegener's granulomatosis.

Suppression of chemotactic activity of neutrophils in hyperosmotic conditions comparable to the renal medulla: partial preservation by phosphoenolpyruvate

Chemotaxis is one of the most important functions of the polymorphonuclear leukocyte (PMN). In the host defense against pyelonephritis, the renal medulla is a site of interaction between bacteria and PMNs. At this site the osmotic pressure is elevated due to a high concentration of NaCl and urea. We evaluated the in vitro chemotactic activity of PMNs under the hyperosmolar conditions created by high concentrations of NaCl and urea. This activity was suppressed by the stimulation of opsonized zymosan and formyl-methionyl-leucyl-phenylalanine. The inhibition of chemotaxis was partially preserved by phosphoenolpyruvic acid (PEP), a precursor of adenosine triphosphate (ATP), in hyperosmolar NaCl but not in urea. The intracellular content of ATP was increased by supplementing the hyperosmolar NaCl with PEP. These observations suggest that inhibition of the chemotactic activity of PMNs is due to differing mechanisms for each NaCl and urea, and that PEP may protect the PMNs against hyperosmolar NaCl by maintaining ATP content.

Effect of recombinant human granulocyte-colony-stimulating factor on renal scarring following infection with MS-piliated bacteria

Renal scars have been thought to occur only in later stages of chronic pyelonephritis. In our experimental pyelonephritis model, bacteria with mannose-sensitive (MS) pili on its surface promoted renal scarring when inoculated into renal parenchyma. Pretreatment with recombinant human granulocyte-colony-stimulating factor (rhGCSF) inhibited the renal scarring which followed inoculation with MS-piliated bacteria, whereas posttreatment at an early stage of infection had no effect on renal scarring. These findings suggest that rhGCSF may be useful for the prevention of infection without increasing the tissue damage to the renal parenchyma which leads to the renal scarring. Even when rhGCSF is used for treatment of kidney infection, it does not promote increased renal scarring through the increased invasion of leukocytes at the inflammatory site.

Regeneration of the rat carotid artery after clipping injury. Part I. A morphological study

We investigated the natural course of the morphological regeneration of the endothelium and smooth muscle of the rat carotid artery after clipping injury. Vascular damage was produced by clipping the right carotid arteries of Wistar rats. Endothelial regeneration was confirmed by the injection of Evans blue dye and the detection of factor VIII-related antigen. The volume of the smooth muscle cell layer and the luminal size were measured by computer-assisted morphometric analysis. Immediately after arterial injury, Evans blue dye freely permeated the smooth muscle layer, suggesting that complete endothelial denudation had occurred. Endothelial regrowth started within 24 hours and was fastest on the third and fourth days after injury. The endothelial injury was repaired within 5 days. The area of the smooth muscle layer did not change immediately after clipping injury, but it gradually increased within a month. The luminal area of the injured artery increased during the 3-month recovery period. These findings suggest that endothelial regrowth is completed within a week after clipping injury, whereas smooth muscle cell regrowth is slower. In addition, arteriosclerotic luminal narrowing did not occur during recovery of the rat carotid artery from clipping injury.

Na+ current kinetics are not the determinants of the action potential duration in neurons of the rat ventral tegmental area

Na+ currents were recorded from two morphological subpopulations of neurons acutely dissociated from the rat ventral tegmental area (VTA). About 45% of 56 VTA cells examined possessed only the ordinary type of Na+ current which was blocked by a low concentration (0.2 microM) of TTX. However, the remaining 55% had the Na+ current which contained a small fraction of the TTX-insensitive component, irrespective of morphological variations and action potential durations of VTA cells. The peak amplitude of the TTX-insensitive component was less than 10% of the peak amplitude of the total Na+ current. The activation and inactivation kinetics of the TTX-insensitive component were much the same as those of the overwhelming TTX-sensitive component of the Na+ current in VTA cells but differed from those of the TTX-insensitive Na+ current reported in peripheral sensory neurons. Thus, it was concluded that the well-known different action potential durations found for subpopulations of VTA cells are not due to multiplicity of Na+ channel kinetics.

Lack of protective immunity against reinfection with hepatitis C virus

Some individuals infected with hepatitis C virus (HCV) experience multiple episodes of acute hepatitis. It is unclear whether these episodes are due to reinfection with HCV or to reactivation of the original virus infection. Markers of viral replication and host immunity were studied in five chimpanzees sequentially inoculated over a period of 3 years with different HCV strains of proven infectivity. Each rechallenge of a convalescent chimpanzee with the same or a different HCV strain resulted in the reappearance of viremia, which was due to infection with the subsequent challenge virus. The evidence indicates that HCV infection does not elicit protective immunity against reinfection with homologous or heterologous strains, which raises concerns for the development of effective vaccines against HCV.

Suppression of intestinal smooth muscle contraction by phenolic compounds

Wood creosote, a mixture of guaiacol, creosol, and other related phenolic compounds, suppresses the spontaneous longitudinal phasic contractions of an isolated rat ileal segment. Thirty-two phenolic compounds were screened for this activity to identify the active substances in wood creosote. Of the 32 compounds tested, 2,3,6-trimethylphenol, 2,4,6-trimethylphenol, and 4-ethylguaiacol were most effective and their respective IC50 values were 0.035, 0.037, and 0.043 mM. Guaiacol and creosol, the chief constituents of wood creosote, were moderately effective and their respective IC50 values were 0.18 and 0.13 mM. Other phenolic compounds in wood creosote also suppressed the ileal contraction although their IC50 values differed markedly from each other. These results suggest that practically all of its constituent phenolic compounds contribute to wood creosote's capacity to suppress ileal contraction.

Slow inactivation of tetrodotoxin-insensitive Na+ channels in neurons of rat dorsal root ganglia

Whole-cell patch-clamp experiments were performed with neurons cultured from rat dorsal root ganglia (DRG). Two types of Na+ currents were identified on the basis of sensitivity to tetrodotoxin. One type was blocked by 0.1 nM tetrodotoxin, while the other type was insensitive to 10 microM tetrodotoxin. The peak amplitude of the tetrodotoxin-insensitive Na+ current gradually decreased after depolarization of the membrane. The steady-state value of the peak amplitude was attained several minutes after the change of holding potential. Such a slow inactivation was not observed in tetrodotoxin-sensitive Na+ current. The slow inactivation of the tetrodotoxin-insensitive Na+ current was kinetically distinct from the ordinary short-time "steady-state" inactivation. The voltage dependence of the slow inactivation could be described by a sigmoidal function, and its time course had a double-exponential process. A decrease of external pH partially antagonized the slow inactivation, probably through an increased diffusion potential across the membrane. However, the slow inactivation was not due to change in surface negative charges, since a shift of the kinetic parameters along the voltage axis was not observed during the slow inactivation. Due to the slow inactivation, the inactivation curves for the tetrodotoxin-insensitive Na+ current were shifted in the negative direction as the prepulse duration was increased. Consequently, the window current activated at potentials close to the resting membrane potential was markedly reduced. Thus, the slow inactivation may be involved in the long-term regulation of the excitability of sensory neurons.

The mechanism of GABAB-mediated slowing of the activation phase of high voltage-activated Ca2+ channels in rat sensory neurons

The mechanism underlying the slowed activation of the high voltage-activated Ca2+ current (HVA-ICa) in the presence of (-)-baclofen was studied in cultured neurons of rat dorsal root ganglia. The decay phase of the baclofen-sensitive component of HVA-ICa was described by a sum of two exponential functions. Although the inhibited portion in the amplitude of the baclofen-sensitive component of HVA-ICa was increased in a concentration-dependent manner, the two decay time constants remained unaffected regardless of the concentration of baclofen. Furthermore, the baclofen-sensitive component of HVA-ICa was largely inactivated by a depolarizing prepulse (-30 mV for 0.5 s). These results support the notion that the slowed activation of the HVA-ICa in the presence of baclofen is due to a preferential inhibition of the inactivating component of HVA-ICa rather than due to voltage-dependent unblocking of a single population of HVA-ICa.

GABAB-mediated modulation of the voltage-gated Ca2+ channels

1. The amino acid, gamma-aminobutyric acid (GABA), activates two different receptor types (Bowery et al., 1980; reviewed by Ogata, 1990a). 2. GABAA receptors are bicuculline-sensitive and are coupled to Cl- channels, while activation of bicuculline-insensitive GABAB receptors has been implicated in the modulation of Ca2+ (Dunlap and Fischbach, 1981) and K+ (Gahwiler and Brown, 1985; Inoue et al., 1985a,b; reviewed by Ogata, 1990b) channels. 3. Baclofen is a specific agonist for GABAB receptors (Bowery et al., 1980). In rat sensory neurones, baclofen suppresses the membrane Ca2+ current (ICa) by a mechanism involving a partussis toxin-sensitive G protein (Holz et al., 1986; Scott and Dolphin, 1986). 4. It has been shown that the inhibitory effect of baclofen is more potent on the early portion of ICa than on the later portion and consequently the rate of ICa activation is slowed (Deisz and Lux, 1985; Dolphin and Scott, 1986). 5. The mechanisms underlying these GABAB-mediated modulation of ICa is not fully understood. This article reviews the inhibitory action of baclofen on ICa in sensory neurones.

Antioxidant effect on renal scarring following infection of mannose-sensitive-piliated bacteria

Renal scars have been considered to occur in later stages of chronic pyelonephritis. In our experimental pyelonephritis model, bacteria which possessed mannose-sensitive (MS) pili on the surface promoted renal scarring following inoculation to the renal parenchyma. Polyethylene glycol-modified superoxide dismutase (PEG-SOD) and 2-O-octadecylascorbic acid (CV3611) significantly suppressed scarring when administered orally or parenterally during the early stage of kidney infection with MS-piliated bacteria. These findings suggest that the superoxide and other active oxygens play an important role in renal scarring following infection and that PEG-SOD and CV3611 may be agents capable of preventing renal scarring following bacterial pyelonephritis.

Comparison of two types of Na+ currents with low-voltage-activated T-type Ca2+ current in newborn rat dorsal root ganglia

Na+ currents and the low-voltage-activated T-type Ca2+ current (T-ICa) were recorded from neurons of rat dorsal root ganglia under similar ionic environments using the whole-cell patch-clamp technique. Two types of Na+ currents were identified on the basis of their sensitivity to tetrodotoxin (TTX) and channel kinetics. One type was blocked by 1 nM TTX and had a faster activation and inactivation time courses (F-INa), while the other type was insensitive to 100 microM TTX and had a much slower channel kinetics (S-INa). Activation thresholds were -60, -40 and -70 mV for F-INa, S-INa and T-ICa, respectively. Peak amplitudes were obtained in respective current/voltage curves at -30 mV (F-INa), 0 mV (S-INa) and -50 mV (T-ICa). The time to peak and the decay time constant measured at potential levels giving peak amplitudes were 0.5 and 1.5 ms for F-INa, 1.4 and 2.9 ms for S-INa and 8.1 and 17 ms for T-ICa, respectively. Cd2+ in a concentration of 50 microM totally blocked T-ICa, whereas it had no effect on either type of Na+ current. T-INa was found in 18 out of 25 cells which possessed F-INs, whereas it was found in only 2 cells among 15 which lacked F-INa. These three types of inward currents having different kinetic and pharmacological properties may mediate diverse functional roles in processing sensory signals.

Use-dependent facilitation of L-like Ca2+ channels counteracts GABAB-mediated inhibition of N-like Ca2+ channels in rat sensory neurons

Baclofen selectively blocked the inactivating N-like component of the high voltage-activated Ca2+ current (HVA-ICa) without affecting the sustained L-like component of the HVA-ICa in rat sensory neurons. The inhibition of the N-like component by baclofen was reversed by a large depolarizing prepulse to +50 mV as a result of facilitation of the L-like component. These results might indicate that a decrease in influx of Ca2+ through N-like Ca2+ channels due to the baclofen-induced block or due to the voltage-dependent inactivation induced by the depolarizing prepulse can be partially compensated by a rapid Ca2+ influx through extra L-like component facilitated by the depolarizing prepulse. Such a compensation of the Ca2+ influx by the use-dependent facilitation of L-like component may be a significant mechanism for adaptive regulation of Ca2+ channels in response to stimulation with a wide range of amplitude and frequency.

Changes in major phospholipids of mitochondria during postischemic reperfusion in rat brain

Major mitochondrial phospholipids were examined in rat brain after 30 minutes of reperfusion following 30- or 60-minute periods of ischemia to examine their changes and explore their relationship to mitochondrial dysfunction during postischemic reperfusion. The amount of phospholipids and the percentage of polyunsaturated fatty acid chains, which tended to decrease during 30 minutes of ischemia, recovered after reperfusion. However, after ischemia lasting for 60 minutes, these parameters did not recover but decreased further, suggesting progressive disruption of phospholipids by phospholipase A2 after reperfusion. These changes were particularly notable in cardiolipin, which is contained specifically in mitochondria. The changes were also closely associated with mitochondrial respiration and respiratory enzyme (cytochrome c oxidase and F0F1-adenosine triphosphatase) activities, which have been known to correlate with the amount of cardiolipin. These results suggest that phospholipid metabolism in mitochondrial membranes is an important factor bearing on the integrity of energy metabolism during postischemic reperfusion.