The usefulness of a continuous administration of tirapazamine combined with reduced dose-rate irradiation using {gamma}-rays or reactor thermal neutrons.

We clarified the usefulness of the continuous administration of tirapazamine (TPZ) in combination with reduced dose-rate irradiation (RDRI) using gamma-rays or reactor thermal neutrons. Squamous cell carcinoma (SCC) VII tumour-bearing mice received a continuous administration of 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) cells. Then, they received a single intraperitoneal injection or 24 h continuous subcutaneous infusion of TPZ in combination with conventional dose-rate irradiation (CDRI) or RDRI using gamma-rays or thermal neutrons. After irradiation, the tumour cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labelling ( = quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total tumour cells was determined using tumours that were not pre-treated with BrdU. The sensitivity of both total and Q cells, especially of Q cells, was significantly reduced with RDRI compared with CDRI. Combination of TPZ increased the sensitivity of both populations, with a slightly more remarkable increase in Q cells. Furthermore, the continuous administration of TPZ raised the sensitivity of both total and Q cell populations, especially the former, more markedly than the single administration, whether combined with CDRI or RDRI using gamma-rays or thermal neutrons. From the viewpoint of solid tumour control as a whole, including intratumour Q-cell control, the use of TPZ, especially when administered continuously, combined with RDRI, is useful for suppressing the reduction in the sensitivity of tumour cells caused by the decrease in irradiation dose rate in vivo.

Role for enhanced faecal excretion of bile acid in hydroxysteroid sulfotransferase-mediated protection against lithocholic acid-induced liver toxicity.

The efficient clearance of toxic bile acids such as lithocholic acid (LCA) requires drug-metabolizing enzymes. We therefore assessed the influence of pregnenolone 16alpha-carbonitrile (PCN) treatment on LCA-induced hepatotoxicity and disposition of LCA metabolites using female farnesoid X receptor (FXR)-null and wild-type mice. Marked decreases in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, and hepatic tauroLCA (TLCA) concentrations were found in LCA-fed wild-type mice co-treated with PCN. Whereas induction of Cyp3a and hydroxysteroid sulfotransferase (Sult2a) proteins was observed in FXR-null and wild-type mice, clear increases in biliary 3alpha-sulfated TLCA but not total 6alpha-hydroxy LCA (taurohyodeoxycholic acid and hyodeoxycholic acid) were only observed in PCN-treated wild-type mice. Biliary 3alpha-sulfated TLCA output rate was increased 7.2-fold, but accounts for only 4.2% of total bile acid output rate in LCA and PCN-co-treated wild-type mice. Total 3alpha-sulfated LCA (LCA and TLCA) was, however, the most abundant bile acid component in faeces suggesting that efficient faecal excretion of biliary 3alpha-sulfated TLCA through escape from enterohepatic circulation. FXR-null mice, which have constitutively high levels of the Sult2a protein, were fed a diet supplemented with 1% LCA and 0.4% dehydroepiandrosterone (DHEA), a typical Sult2a substrate/inhibitor. The faecal total 3alpha-sulfated bile acid excretion was reduced to 62% of FXR-null mice fed only the LCA diet. Hepatic TLCA concentration and serum AST activity were significantly higher in FXR-null mice fed DHEA and LCA diet than in FXR-null mice fed the LCA diet or DHEA diet. These results suggest that hepatic formation of 3alpha-sulfated TLCA is a crucial factor for protection against LCA-induced hepatotoxicity.

The usefulness of continuous administration of hypoxic cytotoxin combined with mild temperature hyperthermia, with reference to effects on quiescent tumour cell populations.

To evaluate the usefulness of continuous administration of hypoxic cytotoxins in terms of targeting acute hypoxia in solid tumours and the significance of combination with mild temperature hyperthermia (MTH) (40 degrees C, 60 min), the cytotoxic effects of singly or continuously administered tirapazamine (TPZ) and TX-402 were examined in combination with or without MTH in vivo. Further, the effects were also analysed on total (=proliferating (P)+quiescent (Q)) and Q cell populations in solid tumours with the method for selectively detecting the Q cell response. C3H/He mice bearing SCC VII tumours received a continuous administration of 5-bromo-2'-deoxyuridine (BrdU) for 5 days to label all P cells. The tumour-bearing mice then received a single intra-peritoneal injection or 24 h continuous subcutaneous infusion of hypoxic cytotoxin, TPZ or TX-402, with or without MTH. On the other hand, to detect the changes in the hypoxic fraction (HF) in the tumours by MTH, another group of mice with or without MTH received a series of test doses of gamma-rays while alive or after tumour clamping. After each treatment, the tumour cells were isolated and incubated with a cytokinesis blocker (=cytochalasin-B) and the micronucleus (MN) frequency in cells without BrdU labelling (=Q cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total tumour cells was determined from the tumours that were not pre-treated with BrdU. The sensitivity to TX-402 was slightly higher than that to TPZ in both total and Q tumour cells. Continuous administration elevated the sensitivity of both total and Q cells, especially total cells. MTH raised the sensitivity of Q cells more remarkably than that of total cells in both single and continuous administrations. It was thought to be probably because of the higher dose distribution of hypoxic cytotoxin in intermediately hypoxic areas derived mainly from chronic hypoxia through MTH. From the viewpoint of tumour control as a whole including both total and Q tumour cells, the continuous administration of hypoxic cytotoxin combined with MTH may be useful for sensitizing tumour cells in vivo.

Influence of alcohol consumption on the association between serum lipids and colorectal adenomas.

BACKGROUND: There have been no reports that low serum cholesterol levels increase the risk of colorectal adenoma, although many studies have shown that they do increase the risk of colorectal cancer. Alcohol intake, which is associated with a risk of colorectal adenomas, and serum cholesterol levels are closely related. The purpose of this study was to evaluate the influence of alcohol consumption on the association between serum cholesterol levels and colorectal adenoma. METHODS: The subjects were 1,349 male patients who underwent both barium enema examination and total colonoscopy. They answered a questionnaire regarding their alcohol consumption history, and their blood samples were analysed. The subjects were divided into three groups: those with no tumour (with neither adenoma nor adenocarcinoma), those with adenoma and those with adenocarcinoma. Among the groups, the serum total cholesterol and triglyceride levels were compared in all the patients, in the patients who did not drink daily and in the patients who did. RESULTS: In all the patients, the serum cholesterol and triglyceride levels did not differ between the patients with and those without adenoma. In the daily drinkers, the serum cholesterol and triglyceride levels were significantly lower in patients with adenoma than in those without. CONCLUSIONS: Significantly lower levels of serum cholesterol and triglycerides were found in daily drinkers with adenoma than in those without.

[Public music concerts in a psychiatric hospital: effects on public opinion and as therapy for patients].

We investigate the effects of music therapy concerts, which were held 60 times over a four year period, 1992 to 1996, in Geiyo Psychiatric Hospital, Kochi Prefecture and found that; 1) Musicians who performed at the concerts were not only from Kochi prefecture but also from other prefectures (10 times) and from four foreign countries (7 times). 2) Live concerts in a small hall had a positive influence on patients and drew the patient's attention and interest away from their hallucinations and delusions to the real world. Moreover, the concerts provided the patients with chances to acquire social graces such as being well-groomed. 3) Explanations by the musicians, interviews with the musicians and the seasonal choruses accompanied by the musicians were helpful to give the patients motives for recovering communication skills and to interact with society. 4) Inquiries to the patients about the concerts indicated discrepancies between the poor observed estimations during the concerts (83.3%) and the good subjective impressions expressed by the patients (82.0%), suggesting that the patients were not good at expressing their internal emotions through facial expressions or attitudes. 5) Many citizens including children came to the concerts and/or gave aid to the hospital because the concerts were open to the public and we suggest that this contributed to improving the general publics' image of psychiatric hospitals. Questionnaires revealed that 90% of people in a control group had a bad image of psychiatric hospitals in Japan, but only 32% of the members of the general public who attended our concerts had a bad image of psychiatric hospitals. In addition, the revolving ratio of the hospital beds rose from 0.4 to 1.2 over the four years, which also suggests a beneficial effect on the patients.

Acarbose improved severe postprandial hypotension in a patient with diabetes mellitus.

Postprandial hypotension (PPH) is defined as a decrease of systolic blood pressure by more than 20 mmHg after meals. Severe PPH is a troublesome diabetic complication, which has no established means of treatment. We encountered a patient who had diabetes mellitus complicated by severe PPH and attempted to treat this problem using several medications (octreotide, midodrine hydrochloride, and acarbose). A 58-year-old male with diabetic triopathy complained of orthostatic dizziness and vertigo after meals. The blood pressure was monitored for 24 h with an ambulatory blood pressure monitor, revealing that the systolic blood pressure decreased markedly after breakfast and dinner by 45 and 50 mmHg, respectively. PPH was not improved by a subcutaneous injection of octreotide. Administration of midodrine hydrochloride reduced the frequency of hypotensive episodes from twice to once daily, but the magnitude of the postprandial fall in blood pressure was still around 30 mmHg. After the patient started to receive acarbose therapy, the postprandial fall in blood pressure was diminished to 18 mmHg and his symptoms largely disappeared. For the treatment of PPH in diabetic patients, our experience suggests that it may be appropriate to try first on alpha-glucosidase inhibitor like acarbose.

A randomized clinical trial of radiation therapy versus thermoradiotherapy in stage IIIB cervical carcinoma.

To clarify the role of thermoradiotherapy for FIGO Stage IIIB cervical carcinomas, both the clinical response and survival of patients treated with radio- or thermoradiotherapy were investigated. Forty patients with Stage IIIB uterine cervix carcinoma were treated with external beam irradiation to the pelvis, combined with iridium 192 high-dose-rate intracavitary brachytherapy. All patients were divided randomly into the following two groups: the radiotherapy (RT) group of 20 patients, who underwent radiotherapy alone; and the thermoradiotherapy (TRT) group of 20 patients, who underwent three sessions of hyperthermia in addition to radiotherapy. The primary endpoint of this study was local complete response and survival. A complete response was achieved in 50% (10 of 20) in the RT group versus 80% (16 of 20) in the TRT group (p = 0.048). The 3-year overall survival and disease-free survival of the patients who were treated with TRT (58.2 and 63.6%) were better than those of the patients treated with RT (48.1 and 45%), but these differences were not significant. The 3-year local relapse-free survival of the patients who were treated with TRT (79.7%) was significantly better than that of the patients treated with RT (48.5%) (p = 0.048). TRT, as delivered in this trial, was well tolerated and did not significantly add to either the relevant clinical acute or long-term toxicity over radiation alone. TRT resulted in a better treatment response and 3-year local relapse-free survival rate than RT for patients with FIGO Stage IIIB cervical carcinoma.

Effect of n-3 polyunsaturated fatty acid supplementation on lipid peroxidation of rat organs.

The present study was undertaken in order to reexamine the effect of n-3 polyunsaturated fatty acid (PUFA)-rich diet supplementation on lipid peroxidation and vitamin E status of rat organs. Male Wistar rats were fed a diet containing safflower or fish oil at 50 g/kg diet and an equal amount of vitamin E at 59 mg/kg diet (1.18 g/kg oil; and 1.5 g/kg PUFA in safflower oil diet, and 4.3 g/kg PUFA in fish oil diet) for 6 wk. Fatty acid composition of total lipids of brain, liver, heart, and lung of rats fed fish oil was rich in n-3 PUFA, whereas that of each organ of rats fed safflower oil was rich in n-6 PUFA. The vitamin E levels in liver, stomach, and testis of the fish oil diet group were slightly lower than those of the safflower oil diet group, but the levels in brain, heart, lung, kidney, and spleen were not different between the two diet groups. The levels of phospholipid hydroperoxides were determined by the high-performance liquid chromatography-chemiluminescence method and the levels of thiobarbituric acid-reactive substances (TBARS) were determined at pH 3.5 in the presence of butylated hydroxytoluene with or without EDTA. Levels of phospholipid hydroperoxides and TBARS in the brain, liver, heart, lung, kidney, spleen, stomach and testis of the fish oil diet group were similar to those of the safflower oil diet group. The results indicate that high fish oil intake does not induce increased levels of phospholipid hydroperoxides and TBARS in rat organs.

Characterization of native and recombinant peptidyl prolyl cis-trans isomerases derived from Methanococcus thermolithotrophicus based on cDNA sequence.

It is important to establish whether a recombinant protein is an authentic copy of the predicted cDNA sequence. In this study, recombinant protein for native peptidyl prolyl cis-trans isomerase (N-PPIase) and double-labeled (13C- and 15N-) protein (DL-PPIase) appeared on the sodium dodecyl sulfate (SDS) electropherograms as two bands for N-PPIase and four bands for DL-PPIase. Since the N-terminal amino acid residues of all bands were the same, we characterized these bands using the peptide mapping method and amino acid composition analysis. Peptide mapping of the proteins seemed to be almost identical but they could not reflect the whole amino acid sequences of the protein. The bands on the polyvinylidene difluoride (PVDF) membrane, electroblotted after SDS-polyacrylamide gel electrophoresis (SDS-PAGE), were hydrolyzed and their amino acid composition was analyzed using a highly sensitive 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) amino acid analysis and compared with the cDNA sequences for proteins. The matching score (sigma(T%-E%)2) for similarity of proteins was calculated by summation of the square difference between the theoretical (T%) and the experimental (E%) amino acid composition of the recombinant protein. The amino acid composition of all bands of both proteins showed more than 93% of the theoretical values. The major molecular weights of both proteins were 16812 and 17694 by electrospray ionization (ESI)-mass spectrometry. However, the purified proteins also contained minor compounds with Mr of 3721 for N-PPIase and 5285 for DL-PPIase. These compounds were considered to be nonpeptidyl products that comigrated with the protein. Similarities of the amino acid composition of the four bands were more than 98%. Our results indicate that AQC amino acid analysis is the most suitable method for characterization of a recombinant protein.

Bax and Bcl-2 protein expression following radiation therapy versus radiation plus thermoradiotherapy in stage IIIB cervical carcinoma.

BACKGROUND: The relative amounts of Bcl-2 and Bax proteins determine cell survival or death following an apoptotic stimulus. To clarify the molecular mechanism of cell death after radiotherapy or thermoradiotherapy and its relation to the response of AJCC/UICC Stage IIIB cervical carcinomas, the expression of Bax and Bcl-2 proteins was investigated both before and in the course of treatment given during this study. METHODS: Thirty-seven patients with Stage IIIB carcinoma of the uterine cervix were treated with external beam irradiation to the pelvis combined with iridium-192 high-dose-rate intracavitary brachytherapy. All patients were randomized to one of the following two groups: the radiotherapy (RT) group of 19 patients who were given radiotherapy alone, and the thermoradiotherapy (TRT) group of 18 patients who were given 3 sessions of hyperthermia in addition to RT. Specimens of the cervical tumors were obtained by punch biopsy both before and in the course of the treatment (after a total dose of 10.8 grays ¿Gy for the RT group or after 10.8 Gy plus 1 session of hyperthermia for the TRT group). The tumor sections were stained with anti-Bax and anti-Bcl-2 monoclonal antibody. On the basis of the percentage of immunopositive cells, both pretreatment and posttreatment samples were scored. Furthermore, relative changes in protein expression were determined by comparing the pretreatment scores with those in the course of treatment. In addition, treatment response was evaluated. RESULTS: A complete response was achieved in 52.6% (10 of 19) of the RT group versus 83. 3% (15 of 18) of the TRT group (P = 0.049). Better tumor control was accompanied by increased Bax expression, i.e., 10.5% (2 of 19) of the RT group versus 44.4% (8 of 18) of the TRT group (P = 0.02). The respective number of patients who partially responded (PR) or did not respond to treatment (NC) was 26.3% (5 of 19) and 21.1% (4 of 19) of the RT group versus 11.1% (2 of 18) and 5.6% (1 of 18) of the TRT group (P = 0.2 for both the PR and NC subgroups). CONCLUSIONS: TRT was found to result in better treatment responses than RT for patients with Stage IIIB cervical carcinoma. An additive or synergistic antitumor effect of TRT is likely to occur through induction of apoptosis involving one of the bax pathways.

(-)-Epigallocatechin gallate inhibits mos activation-mediated xenopus oocyte maturation induced by progesterone.

(-)-Epigallocatechin gallate (EGCG), one of the constituents of green tea known to have a tumor preventing effect, inhibited maturation of Xenopus laevis oocytes induced by progesterone when this polyphenol was microinjected into oocytes at a final concentration of about 1 mM. Western blot and activity measurement analyses showed that Mos translation and the subsequent activations of mitogen-activated protein kinase and p90(rsk), probably by protein phosphorylation, seemed to have been inhibited by the microinjection of EGCG. These results suggest that EGCG may have the ability to control Xenopus oocyte maturation at least during the stage of Mos activation.

Antiviral activity of Sanicula europaea L. extracts on multiplication of human parainfluenza virus type 2.

The antiviral activity of Sanicula europaea L. extracts against human parainfluenza virus type 2 (HPIV-2) was examined. The extract prepared from the leaves of the plant and a fraction separated from the crude extract with gel filtration chromatography were found to inhibit HPIV-2 replication without any toxic effect on Vero cells. The acidic fraction obtained from the crude extract of S. europaea leaves was found to be the most active fraction with plaque inhibition assay at non-cytotoxic concentrations. Unfortunately, antiviral activity was not detected in the molecules purified from the crude ethanol extract of Sanicula leaves.

Dynamic computed tomography predicts tumor temperature and response to thermoradiotherapy in superficial and subsurface tumors.

BACKGROUND: Dynamic computed tomography (CT) was performed on patients undergoing thermoradiotherapy for superficial or subsurface tumors, and the correlation between tumor enhancement and tumor temperature during hyperthermia was evaluated. The authors further investigated whether tumor enhancement by dynamic CT is predictive of tumor response to thermoradiotherapy. METHODS: Thermoradiotherapy was given to 26 patients. Radiotherapy consisted of 40-70 gray. Hyperthermia was conducted over 3-5 sessions, and tumor temperature was measured at each session. Dynamic CT was performed prehyperthermia (within 1 week before the initiation of hyperthermia) and midtherapy (within 1 week after 2 sessions of hyperthermia). RESULTS: A complete response (CR) was obtained in 11 patients (42%) and either a partial response or no response (non-CR) in 15 (58%). There was no correlation between tumor enhancement obtained by prehyperthermia CT and tumor temperature parameters or response. However, the deltaCTmax (maximum increased enhancement) by prehyperthermia and midtherapy CT was 39.0 +/- 18.9 HU and 26.1 +/- 14.2 HU, respectively, in CR patients, and 46.4 +/- 21.1 HU and 49.6 +/- 19.1 HU, respectively, in non-CR patients. This change in deltaCTmax at midtherapy was significantly different between groups (P < 0.01). The deltaCTmax ratio for prehyperthermia and midtherapy CT studies correlated with the average tumor temperature (P < 0.05). CONCLUSIONS: Tumor enhancement by prehyperthermia and midtherapy dynamic CT predicted tumor temperature during hyperthermia and response to thermoradiotherapy for superficial or subsurface malignancies.

Cloning and functional expression of an SGLT-1-like protein from the Xenopus laevis intestine.

A cDNA encoding an Na+-glucose cotransporter type 1 (SGLT-1)-like protein was cloned from the Xenopus laevis intestine by the 5'- and 3'-rapid amplification of cDNA ends method. The deduced amino acid sequence was 673 residues long, with a predicted mass of 74.1 kDa and 52-53% identity to mammalian SGLT-1s. This gene was expressed in the small intestine and kidney, reflecting a tissue distribution similar to that of SGLT-1. The function of the protein was studied using the two-microelectrode voltage-clamp technique after injection of cRNA into Xenopus laevis oocytes. Perfusion with myo-inositol elicited about twofold larger inward currents than perfusion with D-glucose. The order of the substrate specificity was myo-inositol > D-glucose > D-galactose >/= alpha-methyl-D-glucoside. The current induced by myo-inositol increased with membrane hyperpolarization and depended on external myo-inositol and Na+: the apparent Michaelis-Menten constant was 0.25 +/- 0.07 (SD) mM with myo-inositol, whereas the apparent concentration for half-maximal activation was 12.5 +/- 1.0 mM and the Hill coefficient was 1.6 +/- 0.1 with Na+. In conclusion, the cloned protein shares features with both SGLT-1 and the Na+-myo-inositol cotransporter.

Enhancement of antitumor effect of hyperthermia with glucose administration in murine mammary carcinoma.

Antitumor effects of hyperthermia are enhanced by lowering the pH in the tumor tissue with administration of glucose. This decreased pH in the tumor tissue with glucose administration was determined using mouse experimental tumors. 31P-MRS microelectrodes were used for the measurement of pH. By using these two measurement methods, time course change in the tumor tissue was determined in the controls and the groups treated with 6 g/kg of intraperitoneal glucose. The determination of pH with 31P-MRS was calculated from the chemical shift of the peak of creatine phosphate (Pcr) and that of inorganic phosphate (Pi). Following glucose administration, the tumor tissue showed a decrease of 0.3 pH units with the microelectrode method, but did not show any significant decrease in pH with the MRS determination. This finding suggested that 31P-MRS showed intracellular pH (pHi) due to the localization of Pi and that the microelectrode indicated interstitial or extracellular pH (pHe). The ATP/Pi ratio obtained in tumor tissue 24 h after heat treatment (with, without glucose) was correlated with tumor inhibition.

Relevance of a new impedance matching, or subtrap, method for the reduction of pain during hyperthermia.

Capacitive heating is widely used in hyperthermic treatment of human malignancies. However, the pain on the body surface or thermoesthesia in the subcutaneous fatty layer may prevent an elevation of temperature in the tumors. Impedance matching is improved by a subtrap method entailing the application of two copper plates (10 x 850 x 0.06 mm) as a subtrap circuit to each of two capacitive electrodes. In a clinical trial the Tmax, Tave, Tmin for the subtrap method were all higher in comparison with those for the conventional technique (42.5 +/- 0.7 degrees C, 41.9 +/- 1.0 degrees C, 41.3 +/- 1.1 degrees C vs. 41.1 +/- 1.5 degrees C, 40.6 +/- 1.3 degrees C, 40.0 +/- 1.3 degrees C). Although the maximal radiofrequency (RF) power applied to patients was higher with the subtrap method (875 +/- 189 W vs. 763 +/- 200 W), the incidence of surface pain was reduced dramatically. It is concluded that the subtrap method substantially improves the RF capacitive heating of deep-seated tumors.

Change of temperature in mouse tumour tissue immersed in a water bath at 44 degrees C.

We investigated the change in temperature in tumour and normal tissues of mice when immersed in a water bath at 44.0 degrees C as part of a series of studies of hyperthermia. The right hind legs of the mice bearing the experimental tumour sarcoma 180 were immersed in the water bath, and measurements were performed using the multi-thermocouple thermosensor from a radiofrequency (RF) generator every 24 sec with a precision of 0.1 degrees C. The temperature in all tumour tissues exceeded 43.0 degrees C only at 1 min 24 sec after immersion of the limbs. The rise in temperature then reached a plateau phase, and was maintained around 44.0 degrees C. However, we found that the temperature of the normal tissue was about 0.6 degrees C lower than that of the tumour tissue or the tissue around the tumour at the plateau phase.

Effect of n-3 fatty acid supplementation on lipid peroxidation and protein aggregation in rat erythrocyte membranes.

Human erythrocytes in the circulation undergo dynamic oxidative damage involving membrane lipid peroxidation and protein aggregation during aging. The present study was undertaken to determine the effect of n-3 fatty acid supplementation on lipid peroxidation and protein aggregation in the circulation and also the in vitro susceptibility of rat erythrocyte membranes to oxidative damage. Wistar male rats were fed a diet containing n-6 fatty acid-rich safflower oil or n-3 fatty acid-rich fish oil with an equal amount of vitamin E for 6 wk. n-3 Fatty acid content in erythrocyte membranes of rats fed fish oil was significantly higher than that of rats fed safflower oil. The degree of membrane lipid peroxidation and protein aggregation of rats fed fish oil was not significantly higher than that of rats fed safflower oil when the amounts of phospholipid hydroperoxides, thiobarbituric acid-reactive substances, and detergent-insoluble protein aggregates were measured. When isolated erythrocytes were oxidized under aerobic conditions in the presence of Fe(III), the degree of membrane lipid peroxidation of erythrocytes from rats fed fish oil was increased to a greater extent than that of rats fed safflower oil, whereas the degree of membrane protein aggregation of both groups was increased in a similar extent. Hence, n-3 fatty acid supplementation did not affect lipid peroxidation and protein aggregation in membranes of circulating rat erythrocytes, and the supplementation increased the susceptibility of isolated erythrocytes to lipid peroxidation, but not to protein aggregation, under the aerobic conditions. If a sufficient amount of vitamin E is supplied, n-3 fatty acid supplementation may give no undesirable oxidative effects on rat erythrocytes in the circulation.