The influence of Vicia faba (broad bean) seedlings on urinary sodium excretion.

Dopamine (DA) is known to increase diuresis and natriuresis through its action on renal dopaminergic receptors. Augmentation of intra-renal DA concentration by enhancement of its in situ production is greatly dependent on the availability of its precursor L-DOPA to the sites of its renal decarboxylation. Vicia faba (Vf) is a ubiquitous plant rich in easily absorbable L-DOPA. Following ingestion of 40 g freshly chopped Vf containing 120-130 mg of L-DOPA, plasma L-DOPA and urinary sodium and DA excretion increased significantly. The DA/Cre ratio reached a maximum level (280 +/- 58 micrograms/g) 60 minutes after Vf ingestion. This was significantly higher than the DA/Cre ratio after a control meal (1.8 +/- 0.2 micrograms/g; P < 0.0005). The Na/Cre ratio reached the maximal level (2.85 +/- 0.42 mmol/g) 90 minutes after Vf ingestion. This was significantly higher than the Na/ Cre ratio after the control meal (1.4 +/- 0.24 mmol/g; P < 0.005). We suggest that Vf might be of value in treating conditions such as hypertension, heart failure, renal failure, and liver cirrhosis in which natriuresis and diuresis are medically beneficial.

The effect of estrogen replacement therapy on plasma serotonin and catecholamines of postmenopausal women.

We examined the effect of estrogen replacement therapy (ERT) on plasma serotonin (5HT) and norepinephrine (NE) and their correlation with serum estradiol, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in 12 postmenopausal women. Plasma 5HT and NE, estrogen, progesterone, LH and FSH were examined every 4 days for 2 consecutive months (before and during ERT). Serotonin values were low (32.29 +/- 38.36 nmol/l) and showed an intrinsic spontaneous cyclicity with a nadir every 10-11 days. Plasma NE was similar to that observed during the follicular phase of the ovulatory cycle (1,216.8 +/- 503.4 pmol/l) and showed no cyclicity. ERT significantly increased mean (+/- SD) serum estrogen values (from 95.40 +/- 73.31 to 390.72 +/- 347.17 pmol/l, P = 0.0001), significantly decreased serum FSH (from 84.04 +/- 14.97 to 52.97 +/- 20.74 mIU/ml, P = 0.0001) and LH (from 35.35 +/- 13.82 mIU/ml to 29.69 +/- 16.46 mIU/ml, P = 0.03). Plasma 5HT levels showed a tendency to rise under the influence of ERT, but this increase was not statistically significant. Plasma NE decreased significantly from 1,216.8 +/- 503.4 to 994.1 +/- 353.89 pmol/l, P <0.05. In conclusion, plasma serotonin in postmenopausal women has a 10-11 day cycle and is significantly lower than in the follicular phase of ovulating women. Plasma NE shows no cyclicity and is significantly decreased by ERT.

Effect of magnesium on restenosis after percutaneous transluminal coronary angioplasty: a clinical and angiographic evaluation in a randomized patient population. A pilot study. The Ichilov Magnesium Study Group.

Restenosis is a major clinical problem following successful percutaneous transluminal coronary angioplasty. Since magnesium has vasodilator and antithrombotic effects, this study was designed to evaluate its potential to decrease the rate of restenosis. In an open-labelled, randomized controlled study, 148 patients underwent successful coronary angioplasty. Ninety-eight patients were treated with 46-52 mmol/18-20 h intravenous magnesium sulphate (groups M1 and M2), and 49 of them continued with oral supplements of magnesium hydroxide 600 mg.day-1 (group M2). The other 50 patients served as controls (group C). Coronary angiography was performed before, immediately after and at 6 months follow-up or earlier if clinically indicated. Clinical, laboratory, ergometric and radionuclide evaluations were also carried out. One hundred and thirty-nine patients (94%) with 163 dilated segments completed the study. Intravenous magnesium was well tolerated. The cross-sectional area at the site of angioplasty increased by 3.55 +/- 2.01 mm2 in groups M1 and M2 compared with an increase of 2.90 +/- 1.63 mm2 in the control group, (P = 0.03). A trend towards a lower rate of restenosis (> 50% reduction in luminal diameter) was noticed in the magnesium groups (28/110, 25%) compared with the control group (20/53, 38%) P = 0.10. Oral administration of magnesium was well tolerated, did not have an additive effect on restenosis, but an improved clinical course was noted. It is concluded that intravenous administration of magnesium in patients undergoing coronary angioplasty is feasible and safe and that the beneficial trend of magnesium to prevent acute recoil and late (within 6 months) restenosis is encouraging and should promote further investigation in a larger patient population.

Food preferences, body weight, and platelet-poor plasma serotonin and catecholamines.

The possible relationship between body weight, food preferences, and plasma neurotransmitters was investigated in 96 healthy volunteers. The volunteers were divided into groups according to sex, body mass index, and food preferences. In all groups fasting platelet-poor plasma (PPP) norepinephrine and serotonin (5-HT) were examined. PPP-5-HT was low in obese individuals (mean +/- SD: 51.7 +/- 34.6 nmol/L) in comparison with lean individuals (94.31 +/- 85.2 nmol/L; P < 0.01), in lean male carbohydrate cravers (22.7 +/- 16.4 nmol/L) in comparison with protein cravers (132.9 +/- 80.6 nmol/L; P < 0.005) and noncravers (64.7 +/- 51.7 nmol/L; P < 0.05), and in obese male carbohydrate cravers (34 +/- 22.7 nmol/L) in comparison with obese male protein cravers (98.8 +/- 28.4 nmol/L; P < 0.001). In conclusion, PPP-5-HT might be seen as a peripheral indicator of processes linked with food consumption and food preferences.

Broad bean (Vicia faba) consumption and Parkinson's disease.

In 1913, Guggenheim identified L-DOPA in the seedlings, pods, and beans of the broad bean, Vicia faba (VF). Since then, anecdotal cases of symptomatic improvement after VF consumption have been described in patients with PD. In the present study, five healthy volunteers and six PD patients (mean age, 63.5 years; mean disease duration, 13 years; stage III, Hoehn-Yahr scale) ate 250 g cooked VF after 12 hours off medication. Blood samples for L-DOPA measurements (by HPLC-ED) were obtained before eating VF and every 30 minutes, for 4 hours. During this period, a substantial clinical improvement was noted and three patients also showed severe dyskinesias. High plasma L-DOPA values were also measured (Cmax 0.66 to 1.20 micrograms/ml; AUC 1.82 to 4.12 micrograms/ml/H). In addition, their clinical performance and plasma L-DOPA levels were compared to those found after 125 mg L-DOPA + 12.5 mg carbidopa ingested on another day. These data show that VF ingestion produces a substantial increase in L-DOPA plasma levels, which correlates with a substantial improvement in motor performance. Our findings may have implications for the treatment of PD, especially in patients with mild symptoms.

Plasma neurotransmitter profile during different phases of the ovulatory cycle.

The influence of the different phases of the menstrual cycle on platelet-poor plasma norepinephrine (NE) and serotonin (5HT) was examined in 17 normal volunteers. The examinations were performed consecutively during 3 phases of the ovulatory cycle: 1) follicular phase, 2) ovulation, and 3) luteal phase. This investigation was initiated after a preliminary study in 51 volunteers showed wide and consistent variations of plasma NE and 5HT during the different phases of the cycle. Since in this first group the determinations had not been performed consecutively in the same subjects, and the changes observed in the different phases of the cycle could reflect interpersonal variations, the determinations were performed consecutively in a second group, concomitantly with serum estradiol (E2) and LH measurements. The results showed a decrease in plasma 5HT from the follicular phase [144.3 +/- 69.3 nmol/L (+/- SD)] to ovulation (55.7 +/- 41.4; P less than 0.001) and a subsequent increase in the luteal phase (141.3 +/- 96.4; P less than 0.01). The nadir in plasma 5HT showed an inverse correlation with serum LH (r = -0.07). Plasma NE increased from the follicular phase (1226.5 +/- 475.1 pmol/L) to ovulation (1694.0 +/- 564.4; P = 0.027) and reached a maximum in the luteal phase (2335.0 +/- 728.2; P = 0.0034). This rise correlated positively with serum E2. In conclusion, plasma 5HT and NE vary with the different phases of the menstrual cycle. Plasma NE rises during ovulation and seems to to correlate positively with serum E2 levels. Plasma 5HT reaches a nadir during ovulation and correlates inversely with serum LH.

The influence of meal composition on plasma serotonin and norepinephrine concentrations.

Reports concerning changes in plasma neurotransmitter values that result from dietary manipulations have not been published so far. The influence of various meal compositions on platelet-poor plasma (PPP) serotonin (5-HT) and norepinephrine (NE) levels was investigated. Healthy volunteers were subjected to three test meals: a carbohydrate-rich meal (86% carbohydrates), a protein-rich meal (70% protein), and a fat-rich meal (92% fat). After a carbohydrate-rich meal, PPP 5-HT values increased significantly (4.47-fold, P less than .02), whereas a smaller increase (1.66-fold, P = NS) was observed after a fat-rich meal. These effects on PPP 5-HT values could be correlated with insulin plasma levels. A protein-rich meal significantly reduced (P = 0.0011) PPP 5-HT to 28% of initial values, despite an increase in plasma insulin levels. This study has shown that (1) changes in meal compositions influence PPP 5-HT and, to a lesser extent, NE values; (2) the resulting changes in PPP 5-HT levels parallel those reported for brain neurotransmitters; and (3) these results seem to indicate that PPP 5-HT levels may be a model for brain synthesis and release of 5-HT.

The influence of bromocriptine on the pharmacokinetics of levodopa in Parkinson's disease.

Several hypotheses have explained the beneficial effect of adding bromocriptine (BR) to levodopa (LD) in Parkinson's disease (PD) by interaction at the striatal level. In the present study we show the influence of BR on plasma LD values in an acute loading experiment (125 mg LD + 12.5 mg carbidopa [DCI] given alone and together with 2.5 mg BR at 0 time; 4 h observation). On the basis of this influence we have been able to differentiate between three groups of patients: (a) in six patients (five of them with frequent off episodes) LD values were significantly lower (p less than 0.05) when both drugs were given together (area under the curve [AUC] +/- SE 2.10 +/- 0.42 micrograms/ml/h vs. 4.96 +/- 1.10 micrograms/ml/h); (b) in eight patients (one with frequent akinesia) LD levels were significantly higher (p less than 0.003) when both drugs were given together (AUC +/- SE 4.05 +/- 0.51 micrograms/ml/h vs. 1.94 +/- 0.19 micrograms/ml/h); (c) in six patients (without motor fluctuations) no difference in LD levels was noted (AUC +/- SE 3.91 + 0.62 micrograms/ml/h vs. 3.81 +/- 0.70 micrograms/ml/h). The clinical evaluation (Webster scale) did not show substantial differences, except for increased dyskinesia, which correlated with higher LD levels. In summary, we suggest that the diminution of motor fluctuations and the occurrence of dyskinesias when BR is added to LD may stem from changes in LD plasma levels. These findings would be taken into consideration in the interpretation of therapeutic response fluctuations under combined treatment.

Magnesium content of mononuclear cells, erythrocytes and 24-hour urine in carefully screened apparently healthy Israelis.

Twenty apparently healthy Israelis aged 16-52, examined for their history of disease and, carefully screened to exclude concurrent infection or medication, abuse of alcohol or drugs, and pathological findings on routine laboratory estimation, were examined to establish the reference range for the magnesium content of mononuclear cells. The magnesium content of mononuclear cells was estimated according to modified method of Elin & Hosseini (Clin. Chem. 31 (1985) 377-380), together with serum magnesium concentration (S-Mg) and erythrocyte magnesium content. In 10 subjects, aged 23-37 years, 24 h urinary magnesium (U-Mg) was also determined. The mean magnesium content of mononuclear cells was 164.8 fg/cell (SD 28.3 fg/cell). The mean erythrocyte magnesium content was 2.02 (SD 0.16) mmol/l. The magnesium content of mononuclear cells was significantly correlated to U-Mg (r = 0.704, p less than 0.01), suggesting that U-Mg may have a potential value as an index of intracellular Mg content.