Effects of Psilocybe argentipes on marble-burying behavior in mice.

Psilocybe argentipes is a hallucinogenic mushroom. The present study examined the effects of P. argentipes on marble-burying behavior, which is considered an animal model of obsessive-compulsive disorder. P. argentipes significantly inhibited marble-burying behavior without affecting locomotor activity as compared with the same dose of authentic psilocybin. These findings suggest that P. argentipes would be efficient in clinical obsessive-compulsive disorder therapy.

Endothelial dysfunction, carotid artery plaque burden, and conventional exercise-induced myocardial ischemia as predictors of coronary artery disease prognosis.

BACKGROUND: While both flow-mediated vasodilation (FMD) in the brachial artery (BA), which measures endothelium-dependent vasodilatation, and intima-media thickness (IMT) in the carotid artery are correlated with the prognosis of coronary artery disease (CAD), it is not clear which modality is a better predictor of CAD. Furthermore, it has not been fully determined whether either of these modalities is superior to conventional ST-segment depression on exercise stress electrocardiogram (ECG) as a predictor. Thus, the goal of the present study was to compare the predictive value of FMD, IMT, and stress ECG for CAD prognosis. METHODS AND RESULTS: A total of 103 consecutive patients (62 +/- 9 years old, 79 men) with clinically suspected CAD had FMD and nitroglycerin-induced dilation (NTG-D) in the BA, carotid artery IMT measurement using high-resolution ultrasound, and exercise treadmill testing. The 73 CAD patients and 30 normal coronary patients were followed for 50 +/- 15 months. Fifteen patients had coronary events during this period (1 cardiac death, 2 non-fatal myocardial infarctions, 3 acute heart failures, and 9 unstable anginas). On Kaplan-Meier analysis, only FMD and stress ECG were significant predictors for cardiac events. CONCLUSION: Brachial endothelial function as reflected by FMD and conventional exercise stress testing has comparable prognostic value, whereas carotid artery plaque burden appears to be less powerful for predicting future cardiac events.

Comparative predictive and diagnostic value of flow-mediated vasodilation in the brachial artery and intima media thickness of the carotid artery for assessment of coronary artery disease severity.

BACKGROUND: While recent reports suggest that both flow-mediated vasodilation (FMD) in the brachial artery (BA), endothelium-dependent vasodilatation, and intima media thickness (IMT) in the carotid artery correlate with the extent of coronary artery disease (CAD), it is not clear which modality is a better predictor for CAD severity and whether either of these modalities are superior to conventional ST-segment depression in exercise stress electrocardiogram (ECG). Thus, the goal of the present study was to compare the predictive value of FMD and IMT for CAD severity and to evaluate the diagnostic accuracy. STUDY: A total of 103 consecutive patients (62+/-9 years, 79 men) with clinically suspected CAD underwent FMD and nitroglycerin-induced dilation (NTG-D) in the BA as well as measurement of carotid artery IMT by using high-resolution ultrasound, and exercise treadmill testing. Coronary stenosis index (CSI) was calculated from coronary angiography. RESULTS: Seventy-three patients had significant CAD, and 30 patients showed no CAD (NL). FMD was significantly lower and IMT was significantly higher in patients with CAD compared with NL patients (FMD, 3.7+/-3.0% vs. 7.5+/-2.9%; IMT, 1.1+/-0.2 mm vs. 0.7+/-0.1 mm). FMD and IMT correlated to CSI to a similar degree (r=-0.67, r=0.69, respectively), and there was a significant correlation between FMD and IMT. In contrast, NTG-D did not correlate with CSI or IMT. Further, the diagnostic accuracy of FMD and IMT was comparable or even better than that obtained with conventional ST-segment depression during exercise in this cohort. CONCLUSIONS: FMD in BA and IMT could represent a surrogate diagnostic method for assessment of CAD severity.

Provocation of microvessel spasm by low-dose acetylcholine in patients with suspected coronary artery disease--two case reports.

Endothelial dysfunction plays an important role in the pathogenesis of cardiac syndrome X, and intracoronary low-dose acetylcholine infusion is a widely used diagnostic modality for studying the coronary artery endothelial function. The authors herein report 2 cases of cardiac syndrome X with coronary artery endothelial dysfunction and microvessel spasm. The findings of non-invasive testing were positive for ischemia. Coronary angiograms appeared entirely normal in both cases. However, the intracoronary infusion of low-dose (1.5-15 microg/minute) acetylcholine demonstrated an impairment of the coronary blood flow response and consequently provoked an ST-segment elevation in an electrocardiogram. The coronary angiograms showed no spasm in the epicardial arteries. These patients are thus suggested to have cardiac syndrome X with microvessel spasms associated with coronary artery endothelial dysfunction.

Relationship of carotid intima-media thickness, pulse wave velocity, and ankle brachial index to the severity of coronary artery atherosclerosis.

BACKGROUND: Carotid intima-media thickness (IMT), pulse wave velocity (PWV), and the ankle brachial index (ABI) are widely used noninvasive modalities for evaluating atherosclerosis. HYPOTHESIS: The aim of this study was to determine the relationship of carotid IMT, PWV, and ABI with the severity of coronary artery disease (CAD), expressed as the Gensini score, and the presence of coronary risk factors. METHODS: We examined 205 consecutive patients (mean age 65 +/- 12 years) who were clinically suspected of having CAD and were scheduled to undergo coronary angiography. Carotid intima-media thickness, brachial-ankle PWV (baPWV), and ABI were measured in all subjects before they underwent coronary angiography. RESULTS: Of the 205 patients, 124 patients were diagnosed as having CAD based on the presence of >50% stenosis in a major coronary artery; the remaining 81 patients did not have CAD. A relatively good correlation was obtained between carotid IMT and the Gensini score (R = 0.411, p < 0.0001), whereas baPWV correlated only weakly with the Gensini score (R = 0.203, p = 0.0035), and ABI did not correlate with it. A multiple regression analysis revealed that the Gensini score correlated significantly and independently with age, male gender, and carotid IMT. CONCLUSIONS: Of the three noninvasive methods, carotid IMT may be more useful for determining coronary artery atherosclerosis than baPWV or ABI.

Effect of chronic oral supplementation with vitamins on the endothelial function in chronic smokers.

Cigarette smoking has been associated with endothelial dysfunction including impaired endothelium-dependent flow-mediated dilation (FMD). In cigarette smokers, increased oxygen-derived free radicals have been suspected of being one of the major causes of endothelial dysfunction, owing possibly to the inactivation of nitric oxide by free radicals. Vitamins C and E are widely used antioxidant vitamins, which have also been reported to effectively improve the endothelial function in several conditions. To test the effect of moderate-term oral antioxidant vitamin supplementation on the endothelial function in smokers, the authors evaluated the combined effect of vitamins C and E, administered in normal dosages, on FMD in young male smokers. A prospective interventional study was performed. In 15 healthy male subjects (mean age, 24.4 +/-2.5 years old). They studied FMD in the brachial artery by using high-resolution ultrasound. The vascular effects of moderate-term oral supplementation with vitamin C (1.0 g/day) and vitamin E (500 mg/day) were determined during reactive hyperemia, which causes endothelium-dependent FMD. They performed a vascular function study 3 times including before vitamin supplement, after 25 days of vitamin supplement, and 4 weeks after the cessation of the vitamin supplement. The flow-mediated dilator response measurements were repeated twice a day before vitamin supplements, and the repeatability obtained from these measurements was found acceptable (variability of FMD <2%). The oral antioxidant vitamin supplement significantly restored FMD (3.8 +/-2.2% vs 5.9 +/-2.5%; p<0.05), however, this effect disappeared 4 weeks after the vitamin supplementations ended. The combined usual dosage of vitamins C and E supplements was found to improve the endothelial function in chronic smokers.

Endogenous opioids and epinephrine in nitroglycerin provocation tilt test in patients with neurally mediated syncope.

Endogenous opioids and catecholamines are involved in autonomic activity. Nitroglycerin provocation tilt is a useful modality for evaluating neurally mediated syncope. Endogenous opioids and epinephrine might play an important role in nitroglycerin provocation tilt. To investigate whether or not opioids and catecholamines are involved in the pathogenesis of nitroglycerin provocation tilt, we measured the temporal changes of the plasma levels of beta endorphin, norepinephrine, and epinephrine in 64 patients with syncope of unknown etiology, and compared the findings with those of 16 patients who underwent isoproterenol provocation tilt (1-3 microg/min) test with a positive response. We performed a 20 minute control tilt (80 degrees) followed by a nitroglycerin provocation tilt of 20 minutes with the intravenous infusion of nitroglycerin. Nitroglycerin infusion was started at 250 microg/h, and was increased by 250 microg/h every 3 minutes up to 1500 microg/h during the tilt test. Beta-endorphin, norepinephrine, and epinephrine were measured in peripheral venous blood in the supine position 2, 10, and 20 minutes after the start of the tilt test, and also at the onset of syncope. Twenty-six patients had a positive response to the control tilt (group 1), and 22 patients had a positive response to nitroglycerin provocation tilt (group 2). The remaining 16 patients had a negative response to both control tilt and nitroglycerin provocation tilt (group 3), compared with isoproterenol provocation tilt patients (group 4). Beta-endorphin and epinephrine only significantly increased in groups 1 and 2 (beta-endorphin; from 7.3 +/- 3.3 pg/mL to 19.9 +/- 17.7 pg/mL, in group 1, P < 0.05; from 7.3 +/- 2.9 to 16.5 +/- 10.7 pg/mL, in group 2, P < 0.05; epinephrine; from 42 +/- 58 pg/mL to 157 +/- 161 pg/mL, in group 1, P < 0.05: from 33 +/- 25 to 202 +/- 252 pg/mL, in group 2, P < 0.05), but not in groups 3 and 4. Beta-endorphin and epinephrine might participate in the pathophysiology in conventional tilt-induced as well as nitroglycerin provocation tilt-induced syncope in patients with neurally mediated syncope.