The effects of epinephrine (E) on plasma norepinephrine (NE) concentrations and cardiovascular responses before and after beta-blockade were studied in 36 patients with essential hypertension and 10 ...age-matched normal controls. The resting plasma NE and E were significantly higher in the borderline hypertensives (251 +/- 21 (SE) pg/ml, p less than 0.005; 57 +/- 5, p less than 0.05) than in normal controls (127 +/- 18; 38 +/- 7). An immediate rise in plasma E and NE was observed after one bolus intravenous administration of glucagon (1 mg). Then, plasma E fell rapidly to the baseline, whereas plasma NE declined much slowly. Propranolol did not affect the plasma E response to glucagon, but eliminated a prolonged rise of plasma NE. Exogenous E infusion (1.25-1.50 micrograms/min) for 30 min caused a definite rise in both plasma NE and blood pressures and lasted more than 30 min after termination of the infusion. Propranolol did not alter the time course of plasma E, but again inhibited a prolonged rise in both plasma NE and blood pressures. These findings support the view that plasma E can act physiologically as a sustained stimulator to the presynaptic beta-adrenoceptors, leading to an enhancement of NE release and a rise in blood pressure in man.
The effects of dietary potassium on the hemodynamics and plasma norepinephrine (NE) kinetics were studied in 10 patients with borderline hypertension. Potassium supplement (96 mEq daily for 5-7 days) ...induced a significant (p < 0.05) fall in blood pressure and a slight decrease in cardiac output. Both urine volume and urinary sodium excretion increased significantly (p < 0.05) for a first few days following the potassium supplement. The baseline values of the half-time of the rapid NE removal from plasma was significantly delayed in the hypertensive patients (1.05 ± 0.06 min, p < 0.05) when compared with those (0.88 ± 0.04) in normal controls. Potassium supplement induced a significant rise in both plasma NE levels and NE outflow rate (p < 0.01) in the hypertensive patients, while their half-times were significantly shortened (0.89 ± 0.07 min, p < 0.01). The pressor responsiveness to exogenously infused NE tended to diminish during the potassium supplement. These findings indicate that a high potassium intake might accelerate the slowed neuronal NE uptake in the hypertensive patients, while a potassium-induced fall in blood pressure might exert a baroreflex stimulation of NE release. As a net result, an increased NE outflow into the circulation has been confirmed. It is likely that a natriuresis-induced volume contraction might be a predominant factor responsible for the early reduction of blood pressure during the high potassium intake.
The effects of epinephrine (E) on plasma norepinephrine (NE) concentrations and cardiovascular responses before and after β-blockade were studied in 36 patients with essential hypertension and 10 ...age-matched normal controls. The resting plasma NE and E were significantly higher in the borderline hypertensives (251 ±21 (SE) pg/ml, p < 0.005 ; 57 ± 5, p < 0.05) than in normal controls (127 ± 18 ; 38 ± 7). An immediate rise in plasma E and NE was observed after one bolus intravenous administration of glucagon (1 mg). Then, plasma E fell rapidly to the baseline whereas plasma NE declined much slowly. Propranolol did not affect the plasma E response to glucagon, but eliminated a prolonged rise of plasma NE. Exogenous E infusion (1.25 - 1.50 μg/min) for 30 min caused a definite rise in both plasma NE and blood pressures and lasted more than 30 min after termination of the infusion. Propranolol did not alter the time course of plasma E, but again inhibited a prolonged rise in both plasma NE and blood pressures. These findings support the view that plasma E can act physiologically as a sustained stimulator to the presynaptic β-adrenoceptors, leading to an enhancement of NE release and a rise in blood pressure in man.
The effects of sodium depletion of plasma norepinephrine (NE) kinetics were studied in 14 patients with essential hypertension using the steady state NE infusion technique on the theoretical basis of ...a two-compartmental open model. The calculated half time of rapid removal phase (t1/2α) of plasma NE was significantly delayed in the hypertensives (1.20 ± 0.22 min, mean ± SD) than in normal subjects (0.89 ± 0.14) (p < 0.01). The total clearance rates were comparable between the 2 groups (47 ± 7 vs 48 ± 11 ml/kg/min). The rates of the endogenous NE outflow into the circulation (RE-NE) were not significantly different between normal (5.29 ± 1.68 ng/kg/min) and hypertensives (7.69 ± 5.42), although 5 hypertensive patients (36%) showed an increased RE-NE above the normal range. the prolonged half time (t1/2α) in the hypertensives tended to be shortened after sodium depletion induced by either low sodium diet or diuretics (1.04 ± 0.22, p < 0.001). Both plasma NE and RE-NE were significantly increased after sodium depletion. A close correlation was observed between plasma NE and RE-NE (r= 0.907, p < 0.001) in these subjects. These results suggest the slowed neuronal uptake of NE at the sympathetic nerve terminals in some patients with essential hypertension occurring in part as a sodium-mediated consequence.
We developed multimedia applications for demonstrating the usefulness of broadband network for research collaboration and education in the field of material design and bioscience. Michigan State ...University and Japan Science and Technology Corporation were connected by 45Mbps dedicated to international testbed. The collaboration experiments were successfully conducted. We report the background and summary of the experiments and refer to some points that should be paid attention to for making full use of broadband networks.
A multi-center double blind study for the clinical evaluation of TCUK was carried out on 115 patients with cerebral thrombosis. The administration of TCUK was done continuously in doses of 60, 000 I. ...U. for 7 days under comparison with negative placebo. The study was performed according to the protocol, shown in Table 1-6 and the effects of TCUK were judged by the grade of improvement of apparent subjective complaints, disturbances of consciousness, motorius and sensorial disorders of extremities and comprehensive daily life activities. The total scoring of improvements in individual disorders and their comprehensive evaluation were made for judgement of the global improvement and availability of the drugs, obtaining the following conclusions: (1) The availability, particularly the global improvement of TCUK were better than those of placebo in their statistical significance (Table 10). (2) In the serial evaluations, the clinical effects were more significant in patient groups of mild or moderate grades in the severity of disorders, of ages between 40-69, without histories of brain damages and without simultaneous infusions of large amount of solutions. (3) The side effects of TCUK were rare (Table 11) with only two exceptional cases with disturbance of liver functions (Table 18), but the relationship between this liver function disturbance and administration of TCUK was obscure and no cases of hemorrhagic infarction were found in connection with TCUK administration in this study.
PDF
