A Case of Successful Treatment of Femoral Artery Pseudoaneurysm Using Thrombin Injection

No abstract available.

The peroxisome proliferator-activated receptor-gamma agonist, Rosiglitazone, improves aortic wall stiffness in type 2 diabetic patients / 대한내과학회지

BACKGROUND: Diabetes is a major risk factor for the development of coronary artery disease. Atherosclerosis is thought to arise as a result of a chronic inflammatory process within the arterial wall. Insulin resistance is central to the pathogenesis of type 2 diabetes and may contribute to atherosclerosis, either directly or through associated risk factors. Rosiglitazone, a peroxisome proliferator-activated receptor gamma agonist, is used in the treatment of type 2 diabetes mellitus, and previous findings suggest that it may have anti-inflammatory effects on atherosclerosis. This study was performed to evaluate whether rosiglitazone can improve arterial stiffness in type 2 diabetic patients. METHODS: This study consisted of 40 patients with type 2 diabetes. These subjects were classified into two groups either medicated with glimepiride (GLIME group, 61.5+/-8.2 years, M:F = 9:11) or with glimepiride and rosiglitazone (ROSI group, 65.6+/-9.5 years, M:F = 4:16). For each group, plasma a hsCRP, lipid profile, HOMAIR and HbA1c were measured before and after 12 months of medical treatment. At the same time, pulse wave velocity (PWV) using an automatic device (PP 1000, Hanbyul, Jeonju, Korea) was measured. RESULTS: The plasma hsCRP level was significantly decreased in the ROSI group as compared with the GLIME group (4.22+/-4.65 vs. 1.07+/-0.80 mg/L, p=0.025). The carotid-femoral PWV of the ROSI group improved significantly as compared with the GLIME group (8.29+/-1.25 vs. 7.26+/-1.49 m/sec, p=0.024). The changes of PWV were correlated with the changes of hsCRP (r=0.412, p=0.033). CONCLUSIONS: These findings suggest that rosiglitazone can improve the arterial stiffness in type 2 diabetic patients.

Short-Term Effect of High Dose of Vitamin C on Coronary Flow Velocity and Coronary Flow Reserve in Healthy Young Non-Smoker Men

BACKGROUND AND OBJECTIVES: Vitamin C, water-soluble antioxidant, has been reported to restore coronary microcirculatory responsiveness and impaired coronary flow reserve in smokers. However, the effect of high dose of vitamin C on coronary circulation is unclear in nonsmokers. METHODS: We used transthoracic echocardiography to measure the coronary flow reserve, an integrated measure of coronary flow in 20 male healthy nonsmokers (26+/-3 years) before and after administration of the high dose of vitamin C. RESULTS: The coronary peak diastolic velocity was increased by 14.8% after administration of antioxidant vitamin C, whereas the coronary flow reserve did not changed. CONCLUSION: High dose of vitamin C acutely increases the coronary flow velocity without restoration of coronary flow reserve in male healthy nonsmokers.

Alterations of Autonomic Nervous Activity Associated with Spontaneous Coronary Spasm in Patients with Variant Angina

BACKGROUND AND OBJECTIVES: It is now well known that coronary artery spasm plays an important role in the pathogenesis of variant angina. Previous studies have shown that stimulation of the sympathetic or parasympathetic nervous system can provoke coronary artery spasms, although the precise causes of such spasms remain unclear. Power spectral analysis of heart rate variability has been proposed as a noninvasive parameter of autonomic nervous activity. To determine the possible role of the autonomic nervous system in the development of variant angina, we used spectral analysis of heart rate variability obtained from ambulatory Holter monitoring in patients with ST-elevation and chest pain to clarify the alterations of autonomic activity before angina. SUBJCETS AND METHODS: Cardiac autonomic nervous activities were evaluated from the power of the low-frequency and the high-frequency spectral components of heart rate variability obtained from Holter monitoring in a total of 18 episodes of 12 patients with variant angina. Samples during each 10-minute period from 60 minutes before to immediately before an anginal attack were analyzed by fast Fourier transformation. RESULTS: Significant organic coronary stenosis and multiple coronary spasms were detected by coronary angiography in two (20%) and four (40%) of the patients, respectively. The values of the power of the low-frequency component and the low-to-high frequency ratio were significantly greater during the 10-to 0-minute period than during the other 10-minute periods. CONCLUSION: Sympathovagal imbalance - or sympathetic activation without parasympathetic augmentation - enhanced in the 10-minute period before an anginal attack may play an important role in the genesis of coronary artery spasms in patients with variant angina.

Alterations of Autonomic Nervous Activity Associated with Spontaneous Coronary Spasm in Patients with Variant Angina

BACKGROUND AND OBJECTIVES: It is now well known that coronary artery spasm plays an important role in the pathogenesis of variant angina. Previous studies have shown that stimulation of the sympathetic or parasympathetic nervous system can provoke coronary artery spasms, although the precise causes of such spasms remain unclear. Power spectral analysis of heart rate variability has been proposed as a noninvasive parameter of autonomic nervous activity. To determine the possible role of the autonomic nervous system in the development of variant angina, we used spectral analysis of heart rate variability obtained from ambulatory Holter monitoring in patients with ST-elevation and chest pain to clarify the alterations of autonomic activity before angina. SUBJCETS AND METHODS: Cardiac autonomic nervous activities were evaluated from the power of the low-frequency and the high-frequency spectral components of heart rate variability obtained from Holter monitoring in a total of 18 episodes of 12 patients with variant angina. Samples during each 10-minute period from 60 minutes before to immediately before an anginal attack were analyzed by fast Fourier transformation. RESULTS: Significant organic coronary stenosis and multiple coronary spasms were detected by coronary angiography in two (20%) and four (40%) of the patients, respectively. The values of the power of the low-frequency component and the low-to-high frequency ratio were significantly greater during the 10-to 0-minute period than during the other 10-minute periods. CONCLUSION: Sympathovagal imbalance - or sympathetic activation without parasympathetic augmentation - enhanced in the 10-minute period before an anginal attack may play an important role in the genesis of coronary artery spasms in patients with variant angina.

A Case of Complete Heart Block Complicating Bacterial Endocarditis

Active infective endocarditis, involving native, is often complicated by conduction abnormalities. These conduction disturbances are considered to represent an extension of the infection from the valve to the annulus, and to the surrounding myocardium. We describe a case of a 59-year-old woman who presented with dyspnea due to staphylococcal endocarditis, which was complicated by a complete heart block.

A Case of Primary Cardiac Amyloidosis

Amyloidosis is not a single disease entity but a term applied to a complex of disorders associated with deposition of insoluble fibrillar proteins in virtually pure form in various tissues of the body. This disease is encountered sometimes in America or Europe, but rarely in Korea. We had experienced one case of primary cardiac amyloidosis who was admitted to Won Kwang University Hospital due to dyspnea on exertion. This cardiac amyloidosis was confirmed by echocardiogram and endomyocardial biopsy with congo-red stain. We will report a case and review the pertinent medical literature.

The Effect of Protein Kinase C Pretreatment on Gliotoxin Induced Apoptosis in H9c2 Cells / 체질인류학회지

Aspergillus funigatus and other pathogenic fungi synthesize a toxic epidithi- odiopiperzine (ETP) metabolite called gliotoxin. Gliotoxin is an epidithiodiopiperzine compound which can both react with sulfhydryl groups and form hydrogen peroxide. The fungal toxin gliotoxin induces apoptotic cell death in a variety of cells. Apoptosis induced by gliotoxin need calcium but effect of calcium preconditioning is unknown by gliotoxin. We studied the effect of protein kinase C and calcium preconditioning on gliotoxin-induced apoptosis in H9c2 cell. PKC and calcium preconditiong inhibited DNA fragmentation by gliotoxin. From this above results suggest that gliotoxin induce apoptosis via caspase-3 activation, because caspase-3 inhibitor (DEVD-CHO) didn't induce apoptosis in gliotoxin treated H9c2 clls. Calcium and PKC preconditioning inhibit caspase-3 activation by gliotoxin. These data means that PKC preconditioning is related with caspase-3 regulate in gliotoxin-induced apoptosis.

The Role of Echocardiography for Evaluation of the Acute Chest Pain Patients with Nonspecific ECG Findings

OBJECTIVE: To evaluate diagnostic role of echocardiography in the patients of acute chest pain with nonspecific ECG findings we have performed prospective study. SUBJECT AND METHOD: 79 out of 101 consecutive patients presenting to the emergency room with symtoms suggestive of acute coronary syndrome (ACS) without diagnostic ECG change were studied. Presence and score of regional wall motion abnormality (RWMA) were assessed according to the American Society of Echocardiography guideline (16 segment model) by two-dimensional echocardiography within 4 hours after arrival. The diagnosis of acute myocardial infarction (AMI) was confirmed by serial myocardial enzyme assay retrospectively. RESULTS: Of the 28 patients with RWMA, 13 (46%) had non-Q AMI, 8 (28%) had unstable angina, 3 (11%) had posterior AMI. Of the 51 patients with normal wall motion, 10 had gastroesophageal disease, 9 had variant angina, 3 had psychologic disease, 1 had aortic dissection and 1 had hypertrophic cardiomyopathy. Thus, Presence of RWMA by echocardiography had a sensitivity of 49% and a specificity of 88% for diagnosis of ACS. In 21 ACS patients with RWMA, regional wall motion score was significantly higher in AMI than in unstable angina (3.1+/-1.8 vs 1.0+/-2.2, p<0.05). As for the significant coronary artery stenosis, there was a higher incidence of multivessel disease in the patients with RWMA (64%). CONCLUSION: RWMA by two-dimensional echocardiography in the emergency room is not a sensitive but a specific technique to diagnose ACS patient with nonspecific ECG change, especially in posterior AMI and non-Q AMI.

The Role of Doppler Time Index for Evaluation of Left Ventricular Diastolic Function by Patterns of Left Ventricular Hypertrophy in Hypertensive Patients

OBJECTIVE: Recent studies have shown that easily recordable, non-invasive Doppler time index correlates with left ventricular systolic and diastolic function. The aim of present study was to evaluate the significance of Doppler time index by patterns of left ventricular hypertrophy in hypertensives patients. SUBJECTS AND METHOD: This echocardiographic and Doppler study investigated the relationship between left ventricular geometric shape (normal, concentric remodelling, concentric hypertrophy and eccentric hypertrophy) and diastolic function in a 87 patients with essential hypertension and 55 normal subjects. Doppler time index was defined as the summation of isovolumetric contraction (ICT) and relaxation time (IRT) divided by ejection time (ET). RESULTS: Among left ventricular geometric patterns in hypertensive patients, high prevalence of eccentric hypertrophy (32%). Except IVRT in concentric hypertrophic group, no difference were found in Doppler determination of diastolic function between the geometric groups. The Doppler time index significantly correlated with IVRT and deceleration time (DT) of E wave. However, Doppler time index had 71% sensitivity and 89% specificity in assessment of diastolic dysfunction. CONCLUSION: The Doppler time index was significantly correlate with Doppler index of mitral flow. But, this index can be a lesser sensitive indicator of pure diastolic dysfunction.

Alterations of Heart Rate Variability by Vestibular Stimulation in Rabbits

BACKGROUND: There is a substantial evidence that anatomical connections and functional interactions exist between vestibular and autonomic systems. The nature of these interactions, however, is complex and has not been fully defined. Heart rate variability (HRV) was used to investigate the physiological role of the vestibular system on control of heart rate. METHODS: HRV including mean, standard deviation, coefficient of variation (CV), power spectrum was analyzed from R-R intervals of ECG during vestibular stimulation in rabbits. RESULTS: Urethane anesthesia increased heart rate and maintained regular R-R intervals, however, low frequency region/high frequency region (LF/HF) was not changed. In anesthetized rabbits, electrical stimulation of the vagus nerve decreased heart rate and decreased LF/HF by increasing HF. On the contrary, electrical stimulation of the cervical sympathetic nerve increased heart rate and increased LF/HF by increasing LF. Atropine, cholinergic blocker, increased heart rate and increased LF/HF by reducing HF, and propranolol, beta-adrenergic blocker, decreased heart rate and decreased LF/HF by reducing LF. In unanesthetized rabbits, stimulation of the vestibular system induced by rotation or caloric increased heart rate and increased LF/HF by increasing LF. Also electrical stimulation of the vestibular nerve produced the same effects as rotation or caloric in anesthetized rabbits. CONCLUSION: These results suggest that stimulation of the vestibular system increased heart rate not by inhibiting the parasympathetic nerve but by activating the sympathetic nerve.

The Role of Sek1 in Protecting NO-induced Apoptosis in H9c2 cells by Inhibiting Caspase 3 Activation / 대한해부학회지

The stress activated protein kinase, or Jun N-terminal kinase (SAPKs/JNKs), is activated in response to a variety of cellular stresses such as changes in osmolarity and metabolism, DNA damage, heat shock, ischemia, and inflammatory cytokines. Sek1 (JNKK/MKK4) is a direct activator of SAPKs/JNKs in response to environmental stresses or mitogenic factors. Thus, this study was conducted to investigate the role of Sek1 on nitric oxide (NO) induced apoptotic signaling pathway in H9c2 cell. The viability of SNP (Sodium Nitroprusside) treated inactive Sek1 kinase transfectants [Sek1/KI H9c2] is significantly decreased and SNP induce DNA fragmentation in Sek1/KI H9c2. Interestingly, concomitantly with SNP induced injuries, caspase 3-like activity is increased but caspase 1 like activity is not changed in Sek1/KI H9c2. Whereas wild type Sek1 kinase transfectants [Sek1/WT H9c2] is less susceptible to SNP induced apoptosis. In Sek1/KI H9c2, the injuries and DNA fragmentation by SNP is protected by adding Ac-DEVD-AMC, caspase 3 inhibitor. In conclusion, these results suggest that Sek1 plays a role in protecting NO-induced apoptosis and DNA fragmentaion in H9c2 cells by inhibiting caspase 3-like activation.

Arotic Atherosclerotic Plaques as a Potential Embolic Sources in Patients with Cryptogenic Stoke

BACKGROUND: The atherosclerotic plaque in the thoracic aorta has been considered as a potential source of cerebral or peripheral embolization. Especially, complex type of atherosclerotic plaques in the thoracic aorta have strongly been associated with cerebral embolism in ischemic stroke and transesophageal echocardiography(TEE) is a useful diagnostic tool for evaluation of thoracic aorta atherosclerosis. The aim of this study was to evaluate the prevalence and significance of complex type of thoracic atherosclerotic plaques in the patients with cryptogenic stroke who have neither cardiac source nor significant carotid atherosclerosis. METHOD: From 1993 to 1998, TEE and carotid Doppler sonography were performed in 58 consecutive patients with ischemic stroke and in 30 control patients without ischemic stroke. We divided the former into two groups. One is known-cause stroke(n=37) group and the other is Cryptogenic stroke group(n=21). We evaluated cardiogenic source of embolism, thoracic aorta atherosclerotic plaques as well as carotid atherosclerosis by carotid Doppler sonography and TEE. Aortic atherosclerosis was classified as grade 1: normal-appearing aortic intima, grade 2: extensive intimal thickening, grade 3: sessile atheroma protruding 5mm, and grade 5: mobile atheroma. Carotid atherosclerosis was categorized as significant if luminal stenosis of either common carotid artery or internal carotid artery is greater than 50%. RESULTS: 1) There was no statistically significant difference among the three groups in age, gender, diabetes mellitus, hyperlipidemia and smoking. 2) Hypertension was more common in the cryptogenic stroke group(p<0.05). Atrial fibrillation was more common in the known-cause and control group than in the cryptogenic group(p<0.005). 3) The carotid atherosclerosis was found in 7(12%) out of 58 consecutive patients with ischemic stroke. 4) The thoracic aortic atherosclerotic plaque was located primarily on descending aorta. The complex type of plaque was found in 8(38%) out of 21 patients with cryptogenic stroke. The complex type of plaque was found in 10(27%) out of 37 patients with known-cause stroke. The complex type of plaque was found in 3(10%) out of 30 patients with known-cause stroke. CONCLUSION: These results suggest that complex type of thoracic atherosclerotic plaques in cryptogenic stoke can be considered as potential source of ischemic stroke and we suggest that a patient with cerebral embolism without a source identified by the routine transthoracic echocardiograpy or carotid sonography shoud undergo transesophageal echocardiography to evaluate the thoracic aorta atheroma.

A Case of Descending Thoracic Aortic Pseudoaneurysm Associated with Thoracolumbar Pedicle Screw Removal

Vascular injuries after spine surgery may result in acute life-threatening hemorrhage, chronic arteriovenous fistula, or pseudoaneurysm formation. The interval between injury and rupture may range from seconds to years, and accordingly, a high index of suspicion is needed to make the diagnosis. Although acute and delayed vascular injury caused by placement of posterior pedicle screw fixation has been reported, the potential for large vessel disruption during posterior pedicle screw removal has been rarely reported. This case report concerns a 50-year-old man who developed an descending thoracic aortic pseudoaneurysm after posterior pedicle screw removal, diagnosed by chest computed tomography(CT) scan and transesophageal echocardiography(TEE).

The Effects of Therapeutic Duration of Combined Antiplatelets, Aspirin and Ticlopidine, on Coronary Stent Restenosis

BACKGROUND: One of most important mechanisms of coronary stent restenosis is neointimal hyperplasia. Although the process of neointima formation is not fully understood, a special role has been advocated for adherent platelets. Previous studies have shown a clear benefit with combined antiplatelet therapy such as aspirin plus ticlopidine in reducing the rate of thrombotic occlusions of stented vessels. The purpose of this study was to evaluate the effects of duration of antiplatelet regimens on coronary stent restenosis. METHODS: After successful placement of coronary artery stents in 222 patients, we performed follow-up coronary angiograms in 99 patients (42.3%). Forty-six patients were randomly assi-gned to receive aspirin and ticlopidine for four weeks (Group I: 54+/-9 years: M 38, F 8) and 48 patients for 6 months (Group II: 58+/-8 years: M 38, F 10). RESULTS: There were no significant differences in clinical and procedural variables or coronary lesion characteristics before and after stenting. At 6 months after stenting, minimal luminal diameter was 2.16+/-0.93mm in Group I and 2.04+/-1.07mm in Group II (p-0.57). Late lumen loss was 0.80+/-1.07mm in Group I and 0.92+/-1.11mm (p-0.58) in Group II. The stent restenosis rate of Group I at 28.3% and that of Group II at 29.2% were not statistically significant between the two groups (p-0.92). CONCLUSIONS: The therapeutic duration of combined antiplatelet regimen with aspirin and ticlopidine after coronary stent does not affect stent restenosis rate.

Patterns of Exercise-induced Coronary Spasm in Patients with Variant Angina: Results, Correlation with Clinical Features

BACKGROUND: Exercise-induced coronary spasm is occasionally recognized in patients with variant angina, but the patterns of exercise-induced coronary spasm and its relation to clinical features are still not clear. METHODS: Eight consecutive patients with variant angina without significant stenosis of the coronary artery performed serial treadmill exercise tests during early morning, late morning, and in the afternoon. The subjects repeated the tests after administration of atropine and doxazosin or phentolamine. RESULTS: (Upon drug administration), anginal episodes with ST-segment changes (elevation 5, depression 1) Occurred repeatedly in 6 of the 8 patients during early morning; the episodes occurred in only 2 patients during the afternoon exercise test. Four patients showed exercise-induced angina and ST-segment changes during early morning but not in the afternoon, and 2 of them showed mild episodes of exercise-induced angina and ST-segment changes during late morning. Three of the four patients had the characteristic clinical history of angina in early morning during usual activities but not during daytime activities despite the activities being more strenuous. Another 2 patients showed both exercise-induced ST-segment elevation and angina in early morning and afternoon, and they had the characteristic history of more episodes at night and in early morning but only occasionally in the daytime with or without relation to activity. One of the two patients showed intermittent ST-segment elevation during the exercise test. The other two patients had exercise-induced episodes neither in the early morning nor in the afternoon; they had a characteristic history of episodes only at night during sleep but never in the early morning nor in the daytime. Atropine did not suppress the exercise-induced angina in 4 of 5 patients studied. Doxazosin or phentolamine suppressed the exercise-induced episodes in 3 of 5 patients studied but aggravated spontaneous episodes in 3 patients. CONCLUSION: These data suggest that there's possibility of presence of different patterns of exercise-induced coronary spasm, which may be induced by different mechanisms from those in spontaneous episodes in patients with variant angina.

A Case of Torsade de Pointes after Treatment with Terfenadine and Ketoconazole

Torsade de pointes (TdP) is a form of polymorphic ventricular tachycardia that is associated with prolongation of the QT interval. Although it occurs in many clinical settings, torsade de pointes is most commonly caused by drugs. The second generation antihistamines, including terfenadine and astemizole, have little sedation or other adverse effects on the CNS. They have been used widely to treat various allergic diseases, but it has been reported that overdoses or combinations with antifungal agents or macrolide antibiotics may lead to TdP. We report a case of TdP that occured during com-bination therapy of terfenadine and ketoconazole.

The Early Results of Clinical and Angiographic Follow-up after Coronary Interventions for Restenotic Lesions

BACKGROUND: Coronary intervention is a well established treatment of ischemic heart diseases. However, acute arterial occlusion and restenosis have remained as the principal limitations of coronary intervention. This study was aimed to analyze the acute and long-term, and the clinical angiographic results of the coronary intervention for restenotic lesions. METHOD: Between March 1996 and July 1997 at Chonnam University Hospital, second interventions were performed in one hundred restenotic coronary lesions of ninety patients (age 58.5+/-9.0 year, M:F = 5:1), i.e. percutaneous transluminal coronary angioplasty (PTCA) or stent implantation for the treatment of restenosis. RESULTS: 1) Initial interventions were PTCA in 75 lesions (Group I) and stent in 25 lesions (Group II). There were no differences in clinical manifestations, angiographic findings and follow-up period between the two groups. 2) The method of the second intervention for the restenotic lesions after PTCA were either PTCA or stent implantation ; in Group I PTCA was performed in 27 (37%) lesions and stent in 46 (63%), In Group II, PTCA was performed in 20 (91%) lesions and stent in 2 (9%) lesions. The overall success rate of the second intervention for the restenotic lesion was 96%. 3) Follow-up angiogram at 5.5+/-2.9 months after the second intervention revealed the second restenosis rates of 44% (8/18) after stent and 50% (7/14) after PTCA. CONCLUSION: Second intervention for restenotic lesion can be performed with high success rate. Second restenosis rate are not different between the PTCA and stent groups.

Clinical Characteristics of Coronary Interventions in Old Aged Patients

BACKGROUND: Coronary intervention is one of well established therapeutic modalities for patients with ischemic heart diseases. With the prolonged life expectancy and changes in dietary habits in Korea, the number and percentage of elderly patients with ischemic heart disease have increased in interventional coronary therapies. METHOD: There were 1762 patients (age> or = 70 years : 253, age<70 years: 1509) who underwent diagnostic coronary angiogram at Chonnam University Hospital between Jan '96 and Jun '97. We compared clinical characteristics, coronary lesion morphology, success rates and complications of coronary interventions in control and aged groups. RESULTS: 1) Female patients were more prevalent in aged group (43 %; 145 male, 108 female) than in the control group (35%; 982 male, 527 female, p<0.05). 2) The diagnostic sensitivity of coronary angiogram was higher in the aged (169/253, 67 %) than in control group (738/1509, 49 %, p<0.05). Multivessel diseases were more prevalent in the aged (65 %) than in the control groups (49%). 3) Coronary interventions were performed less frequently in the aged group (119/169, 70 %) than in the control group (605/738, 82%, p<0.05). The success rates of PTCA were not different between in the aged (89%) and control (93%) groups, and the success rates in stenting was also not different between the aged (98%) and control (99%) groups. 4) Procedure-related complications (4.6 vs. 7.6 %) and mortalities (0.5 vs 0.8 %) during and after coronary interventions were not different in control and elderly groups. CONCLUSION: Coronary interventions in patients older than 70 years can be performed with high success and low complication rates ; the results do not differ from those of younger patients.

Role of Vestibulosympathetic Reflex on Orthostatic Hypotension in Rats

BACKGROUND: The orthostatic hypotension in response to the assumption of an upright posture is regulated by activation of sympathetic nerves. Role of the vestibular system and neural pathway on orthostatic hypotension were investigated. METHODS: Changes of arterial blood pressure produced by head-up tilting, rotatory stimulation of the vestibular system, or electrical stimulation to the vestibular nerve, vestibular nuclei, and rostral ventrolateral medulla (RVLM) were measured in Sprague-Dawley rats. Also, field potentials were recorded in the vestibular nuclei and RVLM and c-Fos expression was evaluated in the brain stem in order to investigate the vestibulosympathetic pathways. RESULTS: The three phasic blood pressure responses were elicited by head-up tilting: initial fall, early recovery, and late sustained pressure at near control levels, the magnitude of the pressure fall was parallel with the degree of head-up tilting in normal rats. Return position from head-up tilting recovered control level of blood pressure after a brief rapid elevation. However, bilateral labyrinthectomy resulted in exaggerated initial falling and devoid of early recovery phase during postural change. Sinusoidal rotation about off-vertical axis of the vestibular system elicited more elevation of blood pressure than rotation about earth vertical axis. Electrical stimulation of the vestibular nerve, vestibular nucleus, and RVLM produced elevation of blood pressure, which was the most prominent by stimulation of RVLM. Field potentials composed of P, N1, N2 waves in the vestibular nuclei were recorded by stimulation of the vestibular nerve, while weak potentials in RVLM were recorded by stimulation of the vestibular nuclei. An electrical stimulation of the vestibular nuclei expressed c-Fos immunoreactive cells in RVLM. CONCLUSION: These results suggest that the otolith organ of the vestibular system plays a major role in control of orthostatic hypotension, and the pathway of vestibulosympathetic reflex in control of blood pressure involves the vestibular nuclei, RVLM, intermed-iolateral nuclei of the thoracic spinal cord.