Chemosensitivity of patients with recurrent esophageal cancer receiving perioperative chemotherapy.

Perioperative chemotherapy (CT) and chemoradiotherapy are widely used for advanced esophageal cancer. We evaluated the chemosensitivity of patients displaying recurrent esophageal cancer after esophagectomy with perioperative CT. From the database at National Cancer Center Hospital in Tokyo, we extracted recurrent esophageal cancer cases after perioperative CT and evaluated the effectiveness of the first CT against the recurrent disease according to the duration between termination of the original perioperative CT and recurrence with treatment-free intervals (TFIs) 6 months. Systemic CT for their recurrent disease was performed for 30 esophageal cancer patients after perioperative CT. All patients received 5-fluorouracil and cisplatin as perioperative CT, with relapses occurring at TFIs 6 months in 19 patients (all received platinum-containing regimens). The response rate of patients experiencing a recurrence at TFIs 6 months was 0 and 37% (P = 0.029), the median progression-free survival was 2.8 and 4.8 months (log-rank P = 0.001) and the median overall survival was 6.1 and 10.2 months (log-rank P = 0.012), respectively. Recurrence at the TFI

CSF hypovolemia vs intracranial hypotension in "spontaneous intracranial hypotension syndrome".

OBJECTIVES: To investigate the role of CSF hypovolemia in spontaneous intracranial hypotension (SIH) syndrome because so-called SIH syndrome sometimes lacks intracranial hypotension. METHODS: Ten women (aged from 28 to 49 years) with characteristic orthostatic headache without a previous history of dural tear were investigated. In addition to gadolinium (Gd)-enhanced brain MRI, spinal MRI with and without Gd enhancement was performed. RESULTS: Gd-enhanced brain MRI demonstrated diffuse pachymeningeal enhancement in all patients. Sagittal T2-weighted spinal MRI revealed a variable amount of CSF in the extradural space in all patients. Sagittal T2-weighted MRI or axial Gd-enhanced T1-weighted MRI showed dilated epidural veins located in the high cervical portion in each patient. The intensity of dilatation of the epidural veins correlated significantly with the amount of CSF in the epidural space. This suggested that the Monro-Kellie doctrine was applicable in this circumstance. CONCLUSIONS: Since some patients with SIH syndrome have normal CSF pressure and since a downward displacement of the brain due to a reduction of the buoyant action of CSF may induce symptoms, CSF hypovolemia, not intracranial hypotension, may be the cause. Based on the Monro-Kellie doctrine, detecting leaked CSF and venous engorgement (epidural vein dilatation and pachymeningeal enhancement) is an important clue to diagnose so-called SIH syndrome. Dilatation of epidural veins suggests CSF hypovolemia in appropriate conditions.

Hypoperfusion in the supplementary motor area, dorsolateral prefrontal cortex and insular cortex in Parkinson's disease.

The changes of regional cerebral blood flow (rCBF) in Parkinson's disease (PD) were investigated. Because of individual differences in brain volume and the extent of brain atrophy, previous functional imaging studies involved potential methodological difficulties. In this study, using the statistical parametric mapping technique, 99mTechnetium-labeled hexamethylpropyleneamineoxime brain single-photon emission computed tomography images from 18 patients with PD were transformed into standard brain-based stereotaxic coordinate spaces and then compared with such images for 11 control subjects matched for age and extent of brain atrophy. A rCBF decrement in the supplementary motor area (SMA) and such decrement in the dorsolateral prefrontal cortex (DLPFC) were observed in the summarized PD images as compared with controls (p<0.005). In a subgroup in the Hoehn-Yahr III/IV stage (11 cases), the rCBF decrement was demonstrated not only in the SMA, but also in the DLPFC and insular cortex (p<0.001). There was a correlation between the degree of the rCBF decrement in the DLPFC or the insular cortex and the score of the unified Parkinson's disease rating scale (p<0.05), while the rCBF decrement in the SMA showed no relationship with the severity of disease. The function of the SMA is closely associated with the nigro-striatal pathway and its impairment can explain the basic akinetic symptoms in PD, which are responsive to L-DOPA treatment. On the other hand, the DLPFC and insular cortex may play key roles in specific symptoms of impairment at advanced stages, such as impaired working memory, postural instability and autonomic dysfunction. We hypothesize that the impairment of the DLPFC and insular function is correlated with the progression of the disease and is related to DOPA-refractory symptoms, which are major problems in the care of patients with advanced PD.

Accuracy of the functional method of hip joint center location: effects of limited motion and varied implementation.

Accurate location of the hip joint center is essential for computation of hip kinematics and kinetics as well as for determination of the moment arms of muscles crossing the hip. The functional method of hip joint center location involves fitting a pelvis-fixed sphere to the path traced by a thigh-fixed point while a subject performs hip motions; the center of this sphere is the hip joint center. The aim of the present study was to evaluate the potential accuracy of the functional method and the dependence of its accuracy on variations in its implementation and the amount of available hip motion. The motions of a mechanical linkage were studied to isolate the factors of interest, removing errors due to skin movement and the palpation of bony landmarks that are always present in human studies. It was found that reducing the range of hip motion from 30 degrees to 15 degrees did significantly increase hip joint center location errors, but that restricting motion to a single plane did not. The magnitudes of these errors, however, even in the least accurate cases, were smaller than those previously reported for either the functional method or other methods based on pelvis measurements of living subjects and cadaver specimens. Neither increasing the number of motion data observations nor analyzing the motion of a single thigh marker (rather than the centroid of multiple markers) was found to significantly increase error. The results of this study (1) imply that the limited range of motion that is often evident in subjects with hip pathology does not preclude accurate determination of the hip joint center when the functional method is used; and (2) provide guidelines for the use of the functional method in human subjects.

Chemokine receptor expression on T cells in blood and cerebrospinal fluid at relapse and remission of multiple sclerosis: imbalance of Th1/Th2-associated chemokine signaling.

The expression of chemokine receptors on lymphocytes in the blood and CSF of multiple sclerosis (MS) patients was analyzed at relapse and remission. Both CD4+ and CD8+ cells in CSF at relapse were enriched for Th1-type receptors CXCR3 and CCR5 expression, and were reduced for Th2-type receptors CCR3 and CCR4 expression compared with those of the blood. CCR1 and CCR2 expressions on T cells were increased in CSF and blood, respectively. At remission, CCR5 expression, but not CXCR3 expression, was reduced in CSF CD4+ cells. A biased Th1/Th2 balance may play a critical role in active inflammation and CCR5 on CSF CD4+ cells is a good marker of the disease activity.

Linear pontine trigeminal root lesions in multiple sclerosis: clinical and magnetic resonance imaging studies in 5 cases.

BACKGROUND: Magnetic resonance imaging (MRI) is useful for demonstrating demyelinating lesions in patients with multiple sclerosis (MS). Magnetic resonance imaging studies show that MS lesions are generally not uniform in shape, size, or distribution. Linearly shaped lesions at the trigeminal root entry zone have been occasionally reported in single cases of MS, but, to our knowlege, the frequency and the clinical features of such patients have not been comprehensively characterized. OBJECTIVE: To describe the frequency and the clinical and laboratory features of patients with MS who had linearly shaped lesions at the trigeminal root as seen on MRI. DESIGN AND SETTING: A retrospective review of medical records and MRI films of Japanese patients with MS admitted to a university hospital and its affiliated hospital in Sendai, Japan. PATIENTS AND METHODS: Brain MRI films of 74 consecutive Japanese patients with MS (51 females and 23 males) were studied retrospectively and the clinical and laboratory features of the patients with linearly shaped lesions at the trigeminal root were also investigated retrospectively. RESULTS: Five patients (6.8%) were shown to have T1-weighted-hypointense, T2-weighted-hyperintense, nonenhanced linear lesions in the pons on MRI, and these were uniformly localized in the intramedullary portion of the trigeminal root. All of these patients had clinically definite MS and had various types of facial sensory disturbances, such as neuralgia (1 patient), hypesthesia (2 patients), or paresthesia (3 patients). No other clinical or laboratory feature was characteristic in these 5 patients. CONCLUSIONS: Linear pontine trigeminal root lesions were common in our patients with MS. They were associated with various facial sensory symptoms. Since similar lesions are formed in animal models of herpes simplex virus infection, further study is needed to clarify whether these MS lesions are virally induced.

Significant correlation between IL-10 levels and IgG indices in the cerebrospinal fluid of patients with multiple sclerosis.

We measured the interleukin (IL)-6 and IL-10 levels in the plasma and the cerebrospinal fluid (CSF) of a total of 23 relapsing multiple sclerosis (MS) patients [18 with conventional form of MS (C-MS) and 5 with optic-spinal form of MS (OS-MS)] using ELISA and correlated them with the IgG indices and oligoclonal IgG bands (OB) to determine whether these cytokines play a role in the intrathecal immunoglobulin production. IL-10 values in the CSF significantly correlated with the IgG indices and tended to be higher in OB-positive patients. In contrast, IL-10 values in the plasma and IL-6 values in the CSF and the plasma did not correlate with the IgG indices or OB. The CSF-IL-10 value in OS-MS were much lower than those of C-MS, but those of CSF IL-6 did not differ between C-MS and OS-MS. The results remained unchanged even when OS-MS patients were excluded. Our results may suggest a role of IL-10 in upregulating the intrathecal IgG synthesis in relapsing MS.

Increased bilirubins and their derivatives in cerebrospinal fluid in Alzheimer's disease.

Bilirubin, an efficient antioxidant, is the end product of the heme cleavage pathway, which is catalyzed by heme oxygenase (HO) and biliverdin reductase. Although an inducible form of HO is overexpressed in the Alzheimer's disease (AD) brain, it has not been determined whether bilirubin metabolism is actually activated or not. In this study, we measured CSF-bilirubins and their derivatives using an enzyme-linked immunosorbent assay with two kinds of anti-bilirubin monoclonal antibodies, designated 24G7 and 5M2. In AD patients, the levels of CSF bilirubin derivatives increased significantly compared with those of controls. This increase was not due to the increased permeability of the blood-brain barrier, because the levels of unconjugated bilirubin were not different between AD and controls. These data may reflect the increase of degraded bilirubin metabolites in the AD brain derived from the scavenging reaction against chronic oxidative stress.

[A case of Wernicke-Korsakoff syndrome with dramatic improvement in consciousness immediately after intravenous infusion of thiamine].

A 68-year-old man was hospitalized on March 4, 1998 for disturbances in consciousness. In 1995, he had received proximal subtotal gastrectomy and reconstructive surgery of the jejunal interposition for gastric cancer. Thereafter he had been taking enough food without the habit of taking liquor. In October 1997, his short term memory was becoming gradually worse. On February 12, 1998, he suffered from numbness in the feet, and then dysphagia, unsteady gait, and diplopia developed gradually. On February 26, brain MRI showed no abnormalities. On March 3, he had a fever of 38.5 degrees C and his consciousness became unclear. Neurological examination revealed semi-coma, total ophthalmoplegia, and absence of doll's eye movement. Deep tendon reflexes were absent. The serum thiamine level was 9 ng/ml (normal range: 20-50). Brain MRI demonstrated symmetrical high intensity lesions in the periaqueductal area of the midbrain, dorsomedial nuclei of bilateral thalami, and vestibular nuclei. About 30 seconds after intravenous infusion of thiamine, his consciousness improved dramatically, but returned to semi-coma after about two minutes. Wernicke-Korsakoff syndrome usually occurs acutely. In the present case, however, the disease showed slow onset, chronic progression, and then rapid worsening after fever. Reconstructive surgery of the jejunal interposition might have caused the slow onset of Wernicke-Korsakoff syndrome, and fever might have facilitated the rapid progression of the disease. An immediate high concentration of thiamine modifies the kinetics of acetylcholine receptor ion channels, thereby maintaining wakefulness, and the level of consciousness may change dramatically.

[An autopsy case of motoneuron disease with dementia of long duration].

An autopsy case of MND with dementia, 67 years old, man, was reported. The behavioral disturbance appeared at 61 years old, and was followed by the upper limb weakness and respiratory failure. He had remained on a respirator for 56 months. The total duration of the disease was 74 months, which was far longer than mean duration of the cases previously reported, 25-30 months. The pathological findings were about essentially identical to those mentioned before, such as cortical alterations in temporal and frontal lobes, neuronal loss with gliosis in amygdaloid body and substantia nigra, and loss of lower motoneurons in anterior horn of spinal cord and in the several motor cranial nerve nuclei. There were several Bunina bodies in the remnant lower motoneurons, but no changes in the pyramidal tracts or loss of Betz cells in the precentral gyrus. Intracytoplasmic ubiquitin-immunopositive inclusions in the granule cells of hippocampal dentate gyrus were also encountered, but the number of which did not increased, compared to the preceding data. There may be frequently little correlation between the disease duration and the number of such inclusions. The regional alteration in the intermediate zone between subiculum and entorhinal cortex was revealed also at the level of the splenium of corpus callosum. It has been reported that such parahippocampal lesion may initiate at the anterior part of temporal lobe and become undiscernible at more posterior level than the lateral geniculate body. The formation of such parahippocampal lesion may be concerning with the length of disease duration. In addition, there were numerous senile plaques, diffuse or neuritic type only in the parietal lobe cortex without any other changes.

[A case of encephalomyeloneuritis and HTLV-I infection].

The patient, a 65-year-old woman, had liver cirrhosis, and had blood transfusion at the age of 49 and 56. Early in September, 1989, she gradually developed numbness of the legs, staggering gait, and apathy with hallucination. In October, she became incontinent and unable to stand, and was admitted to Konan Hospital. On admission, she was disoriented with poor comprehension. Cranial nerves were intact except for horizontal nystagmus on lateral gaze. She had generalized areflexia without pathological reflex. Muscular forces were fairly preserved. Superficial sensations were diminished in the upper limbs as well as below Th-7 level. Deep sensation was abolished in the distal parts of the extremities with athetotic finger postures on arm rising. She had urinary and fecal incontinence. Results of routine laboratory examinations were non-contributory. Chest CT scan and sputum cytology were normal. CSF contained one cell/microliter, 95 mg/dl of protein with positive oligoclonal IgG bands. Anti-HTLV-I antibody was positive in serum and CSF. Urodynamic studies showed neurogenic bladder of supranuclear type. MNCV was slightly decreased. SNAP and SEP were not evoked. On sural nerve biopsy, the density of myelinated fibers was 720/mm2, and that of unmyelinated fibers, 26,978/mm2. ABR and VEP were abnormal. EEG showed diffuse theta waves with paroxysmal delta and sharp waves. T2-weighted MR images of the brain showed patchy areas of high signal intensity in the cerebral white matter. Soon after administration of methylprednisolone, her consciousness became clear. EEG normalized in 4 months. Twenty months after the onset, she became ambulant with crutch, but still has dysuria and sensory deficits in the hands and lower limbs. The possible relationship between encephalomyeloneuritis and HTLV-I infection was discussed.

[A case of limbic encephalitis associated with breast cancer developed in an HTLV-1 carrier].

We here present a case of 44-year-old woman, a carrier of human T-lymphotrophic virus type-1 (HTLV-1), who suffered from limbic encephalitis and breast cancer. In December 1997, the patient's behavior became abnormal. Three weeks later, she became markedly forgetful. At that time neurological examinations revealed that she had anterograde and retrograde amnesia, disorientation, and confabulation, although her consciousness was clear. Anti-Hu and anti-Yo antibodies and antinuclear antibodies in the serum were negative. Flow cytometric study of the peripheral blood lymphocytes showed an increased percentage of CD3+CD25+ cells, although the percentages of CD4+CD45RA+ and CD4+CD45RO+ cells were normal. Lymphocytic responses to phytohemagglutinin or concanavalin A were normal. Anti-HTLV-1 antibody was positive both in the serum and in the cerebrospinal fluid (CSF). The level of immunoglobulin G was high and two oligoclonal immunoglobulin G bands were positive in the CSF. Cytological study of the CSF showed no atypical cells. Findings for herpes simplex virus type I and II DNAs were negative with polymerase chain reaction in the CSF. There was no elevation of antibody titers against viruses including herpes simplex virus, cytomegalovirus, and measles virus, either in the serum or the CSF. Magnetic resonance imaging showed signal abnormalities in the medial portions of both temporal lobes, in particular, in the bilateral hippocampus. Six weeks after the onset, a cancerous tumor in her right breast was detected and removed by open surgery. The pathological diagnosis was invasive ductal carcinoma with neuroendocrine features. After mastectomy, anterograde and retrograde amnesia and disorientation mildly improved. The follow-up magnetic resonance imaging showed that signal abnormalities in the medial portions of both temporal lobes decreased and that the bilateral hippocampus became atrophic. We diagnosed the present case as paraneoplastic limbic encephalitis. There has been only one case report of limbic encephalitis associated with breast cancer.

Clinical and MRI study of brain stem and cerebellar involvement in Japanese patients with multiple sclerosis.

OBJECTIVES: To investigate the clinical and MRI features of brain stem and cerebellar lesions in Japanese patients with multiple sclerosis. METHODS: A retrospective study of 66 consecutive Japanese patients with multiple sclerosis (42 women and 24 men) was done by reviewing the medical records and MRI films. Forty nine patients were diagnosed as having clinically definite multiple sclerosis and 17 patients as having clinically probable multiple sclerosis according to Poser's criteria. Prevalence rates of each brain stem and cerebellar manifestation and frequency and distribution of MRI lesions in these patients were studied. RESULTS: Forty three patients (65%) had one or more infratentorial manifestations. Cranial nerves were clinically involved in 28 patients (42%), and most of the lesions were identified by MRI. Among them, manifestations of facial, trigeminal, and abducens nerves were relatively common. Cerebellar ataxia was found in 20 patients (30%). The MRI study showed that the lesions responsible for ataxia in these patients were mainly found in the cerebellar peduncles, but cerebellar hemispheric lesions were detected in only four patients (6.4%). CONCLUSION: The low frequency (6.4%) of the cerebellar MRI lesions in these patients is in sharp contrast with the figures reported for white patients with multiple sclerosis (50%-90%). Racial and genetic differences may have an influence on the susceptibility of each part of the CNS to demyelination in multiple sclerosis.

Clinical and laboratory features of myelitis patients with anti-neutrophil cytoplasmic antibodies.

Although perinuclear anti-neutrophil cytoplasmic antibodies (pANCA) are associated with vasculitic neuropathy, their association with central nervous system (CNS) disorders has not been studied except for one report on optic-spinal type of multiple sclerosis associated with serum pANCA. We examined pANCA in sera from 98 patients with various CNS disorders, such as 58 MS, 17 myelitis, 12 HTLV-1 associated myelopathy, and 11 other CNS diseases using indirect immunofluorescence methods. The results showed serum pANCA to be positive in five patients with a peculiar type of myelitis, including two with MS and three with etiology unknown myelitis. All of these ANCA-positive patients were women and had acute or subacute myelopathy with various severities. MRI revealed segmental swelling of the spinal cord with T2 hyperintensity in the acute stage of the disease. Marked pleocytosis (227.8+/-101/mm3) and elevated protein level (128.8+/-52 mg/dl) in CSF were noted. Four of the patients had anti-nuclear antibodies and two had previous histories of symptoms suggesting autoimmune disorders. In a search for target antigens of pANCA, myeloperoxidase reactivity was found in the sera from two myelitis patients. Clinical and laboratory features of myelitis patients with pANCA in the present study are different from those of typical MS patients. Further study will be needed to delineate the role of pANCA in the pathogenesis of a specific type of myelitis.

Structural alteration of linear plasmids encoding the genes for polychlorinated biphenyl degradation in Rhodococcus strain RHA1.

Polychlorinated biphenyl (PCB) tolerant derivatives of a strong PCB degrader, Rhodococcus strain RHA1, were selected after growth in the presence of 100 micrograms/ml PCBs. Some of the derivatives did not grow on biphenyl but accumulated a yellow coloured metabolite suggesting a defect in the meta-ring-cleavage compound hydrolase step encoded by the bphD gene. Other derivatives failed to grow on biphenyl and exhibited little PCB transformation activity suggesting a defect in the initial ring-hydroxylation dioxygenase step encoded by the bphA gene. These organisms had a structural alteration in the linear plasmids coding for the bph genes in RHA1, which included the bph gene deletion. When a bphD containing plasmid was introduced into a tolerant derivative, RCD1, which was shown to have bphD deletion, the defect in the growth on biphenyl of RCD1 was overcome. The bph gene deletion seems to play a key role in these tolerant derivatives thereby suggesting that the toxic metabolic intermediate would be a main cause of the growth inhibition of RHA1 in the presence of high concentration PCBs.

Microsatellite polymorphism in the human heme oxygenase-1 gene promoter and its application in association studies with Alzheimer and Parkinson disease.

Oxidative stress has been suggested to be involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer disease (AD) and Parkinson disease (PD). Heme oxygenase-1 (HO-1), a key enzyme in heme catabolism, also functions as an antioxidant enzyme. Here, we show that a (GT)n repeat in the human HO-1 gene promoter region is highly polymorphic, although no particular alleles are associated with AD or PD. This newly identified genetic marker should allow us to study the possible involvement of HO-1 in certain human diseases.

The differential involvement of von Willebrand factor, fibrinogen and fibronectin in acute experimental thrombosis in rat cerebral and mesenteric microvessels.

Arterial thrombi are primarily composed of platelets. Platelets are bound to injured endothelial cells, sub-endothelial matrices, and other platelets by a range of adhesive proteins. Some of these reactions are governed by shear forces. The role of adhesive proteins in the pathogenesis of arterial thrombosis is not fully understood. The aim of this study was to examine the involvement of von Willebrand factor (vWF), fibrinogen (Fg), and fibronectin (FN) in the formation of microvascular thrombi in vivo using a helium-neon laser-induced thrombosis method. Transmission electron microscopy demonstrated that laser irradiation resulted in platelet-rich thrombosis in arterioles and venules, and revealed that this occurred in the absence of endothelial denudation. The mean wall shear rates in mesenteric arterioles and venules were 641 +/- 40 and 280 +/- 20 s-1, respectively. Shear rates increased approximately fivefold in arterioles and tenfold in venules during the formation of occlusive thrombi. Antibody to vWF inhibited thrombosis in arterioles and venules. Antibodies to Fg and FN inhibited thrombosis in venules but not in arterioles. These results confirm that vWF, Fg and FN were involved in thrombogenesis in vivo and demonstrated that significantly higher shear rates were required for the reactions involving vWF than those involving either Fg or FN.

[Immunoadsorption therapy for Fisher's syndrome: analysis of the recovery process of external ophthalmoplegia and the removal ability of anti-GQ1b antibodies].

The beneficial effect of plasma exchange, plasmapheresis or immunoadsorption therapy on Fisher's syndrome, suggested previously, has not been proved since no controlled studies have been conducted. In order to assess the effect of any treatment on Fisher's syndrome, simple and reasonable grading scales for evaluating the major neurological signs are needed. We tried immunoadsorption therapy in four patients with Fisher's syndrome, whose sera had anti-GQ1b antibodies. The clinical course was observed, with assessment of the severity of the major neurological signs based on grading scores; ranging from 0 to 30 for external ophthalmoplegia, from 0 to 10 for ataxia, and from 0 to 16 for areflexia. Tryptophan- or phenylalanine-linked polyvinyl alcohol gel column (TR-350, PH-350) was used as an adsorbent. In a patient who had IgG anti-GQ1b antibody and another patient who had both IgG and IgM anti-GQ1b antibodies, we compared the effectiveness of TR-350 and PH-350 to remove the anti-GQ1b antibody during the therapy. Two patients underwent immunoadsorption therapy at the height of clinical manifestations: in one patient, the therapy was discontinued because of critical hypotension and arrhythmia; the other was given only three sessions of therapy. The other two patients received six or seven sessions during the early recovering stage. All patients recovered without major neurological sequelae. Since ataxia was improved earlier than external ophthalmoplegia, the duration of hospitalization and the time of return to social life depended upon the recovery of external ophthalmoplegia. Analysis of the time course of external ophthalmoplegia score indicated that the improving period and the 50%-recovery day came earlier in the patients who were given a sufficient number of sessions than those who received an insufficient number of sessions. The treatment with TR-350 reduced the IgG anti-GQ1b antibody titer more than that with PH-350, but reduced the IgM anti-GQ1b antibody titer similarly. Immunoadsorption therapy using TR-350 has a probable beneficial effect on Fisher's syndrome even though it is carried out after the height of illness. The evaluation method for the severity of external ophthalmoplegia that we used in the present study is useful for assessing the effect of therapy on Fisher's syndrome.

Cerebral prothrombotic state in spontaneously hypertensive rats of different breeds.

The thrombotic tendency in two breeds of spontaneously hypertensive rats (SHRs) was assessed by inducing occlusive thrombosis in pial blood vessels using a helium-neon laser method. A prothrombotic state was observed in the SHR of one breed as compared to the corresponding control WKY, but not in the other. Circulating platelet and erythrocyte counts and haematocrit values were significantly negatively correlated in arterioles with the number of laser pulses, which is an index of the thrombotic tendency, suggesting that the prothrombotic state was partly dependent on the counts of blood components. However, there was no correlation between the measured blood parameters and prothrombotic state in venules. The difference observed in arterioles and venules might be due to their differential haemodynamics and endothelial properties. Prothrombotic state in the SHR of one breed would be partly due to the much higher difference in blood components from its corresponding control compared to the comparatively less difference in the other breed.