James W. Woods

Increased Red-Cell Sodium-Lithium Countertransport in Normotensive Sons of Hypertensive Parents

MOST investigators would agree that both heredity and environment are important determinants in the development of essential hypertension. Among the environmental factors, dietary sodium has a prom...

Renin Profiling in Hypertension and Its Use in Treatment with Propranolol and Chlorthalidone

We compared methods of classifying hypertension according to plasma renin activity in 54 patients with essential hypertension and examined the validity of using these classifications to choose between two hypotensive drugs. A prospective, double-blind crossover study was used. Normal values for plasma renin activity were established from 111 control subjects. Plasma renin activity was related to race and inversely to age in hypertensive patients (P less than 0.05) but not in normal subjects. Three methods of classification correlated well but did not identify exactly the same renin-suppressed patients. Chlorthalidone produced a greater reduction in blood pressure and restored blood pressure to normal in a larger percentage of patients in both low-renin (59 per cent) and normal-renin (32 per cent) subgroups than propranolol (12 and 16 per cent). Renin determinations are of limited benefit in the choice of therapy for most patients with essential hypertension.

Management of Malignant Hypertension Complicated by Renal Insufficiency

Abstract Aggressive hypotensive-drug therapy combining a thiazide diuretic, hydralazine and guanethedine was used in 20 patients with malignant hypertension complicated by renal insufficiency. Elev...

Intravenous diazoxide therapy in hypertensive crisis

Ninety-one doses of diazoxide were administered intravenously to 41 patients with hypertensive crises. Diastolic blood pressure was reduced from an average of 139 to 98 mm Hg within 10 minutes. On the basis of a retrospective analysis of the response of diastolic blood pressure, it was possible to determine within 10 minutes of injection whether a second dose would be required. Therapy was judged to be effective in 38 of 41 patients; 35 percent of injections were ineffective. Concomitant administration of furosemide was not shown to have a beneficial antihypertensive effect. Mean blood urea nitrogen was 59.5 mg/100 ml initially and was not significantly different 2 weeks after therapy. None of the patients demonstrated clinical evidence of diazoxide-induced deterioration of coronary circulation. Electrocardiograms obtained 2 weeks after diazoxide therapy failed to show evidence of new ischemic changes. Only 9 percent of patients complained of side effects, and these were transient and relatively innocuous. It is concluded that diazoxide is both safe and efficacious in the management of hypertensive crises.

Non-Obstructive Escherichia coli Pyelonephritis in the Rat.

Summary An experimental model for study of non-obstructive E. coli pyelonephritis in the rat and successfully employing use of“clean-voided”urine specimens for quantitative culture has been described. It appears that some strains of E. coli may persist for long periods in the urinary tract and that minute lesions may be responsible for bacteriuria.

Renal Vein Renin and Juxtaglomerular Activity in Sodium-Depleted Subjects

Ten patients requiring surgery for renal cysts or calculi and having no evidence of secondary hyperaldosteronism were divided, as volunteers for special study, into experimental and control groups. After base line studies, the experimental group was given a diet containing 87 mEq of sodium and 1.0 g of chlorothiazide daily for ten days. Control subjects ate a normal diet. At operation, samples of peripheral and renal venous blood were obtained for measurement of renin activity and renal biopsy was taken for determination of the juxtaglomerular index. Increased renin in renal venous plasma and hypergranularity of the juxtaglomerular apparatus were found in sodium-depleted subjects but not in control subjects. These findings confirm results previously found in animals.

Echocardiographic Assessment of the Effect of an Antihypertensive Regimen on Left Ventricular Performance

A regimen consisting of chlorthalidone, hydralazine and propranolol would be useful in some hypertensive patients with coronary artery disease or aortic dissection if it could be shown that reflex cardiac stimulation induced by hydralazine is completely neutralized by propranolol. Nine hypertensive patients were treated with chlorthalidone during week 1, chlorthalidone and hydralazine during week 2 and a combination of chlorthalidone, hydralazine and propranolol during week 3. Blood pressure, heart rate, mean velocity of circumferential fiber shortening (VCF) measured echocardiographically and plasma renin activity were measured weekly. This potent three drug regimen reduced mean blood pressure from 142 to 102 mm Hg, and with the third drug, propranolol, heart rate, VCF and plasma renin activity returned to control levels from the greater elevated levels produced by the diuretic drug and hydralazine. In six additional patients VCF (an index of left ventricular contractility) was found to be proportionate to the rate of rise of aortic pressure (dP/dt) or aortic shearing force. This regimen appears safe for use in patients with ischemic heart disease and aortic dissection.

Catecholamine excretion in young white and Negro males with normal and elevated blood pressure

Abstract This study was designed to compare the urinary excretion of norepinephrine and epinephrine in young hypertensive Negro males with excretion in normotensive Negro and white males of similar age and social class. Diet, physical fitness, physical activity, drug usage, and use of nicotine were considered. Day-night differences in catecholamine excretion, reproducibility of individual and group catecholamine excretion rates on two occasions and a comparison of catecholamine excretion by normotensive and hypertensive subjects during a period of limited activity on a metabolism ward and a period of usual activity outside the hospital were studied. No significant differences were found in catecholamine excretion between Negro and white or between hypertensive and normotensive young males either on a metabolism ward or during their usual daily activities. The premature and excessive occurrence of hypertension in the Negro does not appear to be related in its early sustained period to sympathomimetic overactivity to the extent that the latter process is reflected in catecholamine excretion rates.

Contraceptive steroids and hypertension: an experimental model.

Summary The effect of contraceptive steroids on a strain of rats genetically predisposed to develop hypertension from ingestion of an excess of NaCl has been examined. Rats given CS grew more slowly and had a lower weight regardless of salt intake. CS enhanced the hypertension of rats receiving the high-salt diet but not of those eating a low-salt diet. CS had no effect on survival but salt intake did. This model offers the opportunity of studying the mechanism by which gonadal steroids enhance hypertension.

Interrelationships of Oral Contraceptives and Hypertension

The large, carefully controlled, prospective studies needed to define the association between oral contraceptives and hypertension have not been published and the information to date is largely anecdotal. That there is an association, however, appears to be widely accepted among practicing physicians. To our knowledge, only the 29 cases listed in Table 1 have been reported.