Enalapril: a new angiotensin-converting enzyme inhibitor.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to A Fitz.
Explore the source record for details and available documents.
We studied urinary kallikrein excretion in the rat during unilateral release of 24-hr bilateral ureteral ligation (BUL). In six rats studied after 24 hr of BUL, the glomerular filtration rate was 20 per cent of that in the five sham-operated controls. In the BUL group, the urine flow rate was 5 fold greater, fractional sodium excretion 100 times greater, and fractional potassium excretion 5 times greater than in controls. Urinary kallikrein excretion in the BUL group was one-half that of the controls. However, urinary kallikrein excretion per functioning nephron was increased 3 fold in the BUL group. Five of six BUL rats with increased fractional sodium and water excretion also showed increased urinary kallikrein excretion/GFR when compared to controls. Our study suggests that after 24 hr of BUL in the rat, urinary kallikrein excretion is increased in relation to the remaining, functioning nephrons and suggests a role for the kallikrein-kinin system in the postobstructive salt and water losses.
Pretreatment of hog high molecular weight renin for 30 min at 37 degrees C with 0.12 unit of either kallikrein or thrombin significantly increased (p less than 0.001) the amount of angiotensin I formed during subsequent incubations with homologous angiotensinogen. However, the thrombin-treated hog renin had 13 times more activity than the kallikrein-treated enzyme. Aprotinin did not inhibit the kallikrein-mediated activation of renin; the results indicated that aprotinin inhibited renin preferentially. Plasmin (0.25 unit) had little effect on the activity of high molecular weight renin. The molecular weight of hog renin on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was not altered after exposure to either kallikrein, thrombin, or plasmin. These results do not exclude the occurrence of a limited proteolytic event or a conformational change beyond the detection of the current method. The data show that the activation of hog high molecular weight renin by thrombin and kallikrein was not associated with the conversion of renin to Mr = 43,000.
The relationship of serum dopamine-beta-hydroxylase (DBH), plasma renin activity (PRA) and urinary catecholamines (IU catechols) in various forms of essential hypertension (EHT) (low, normal and high renin) was evaluated. Eighty-four predominantly white, young (37 +/ 8 years (SD)), mildly hypertensive patients (diastolic pressure 93 +/- 4 mm Hg (SD)) continued their regular diet and received no medications. Thirteen patients had low-renin, 64 had normal-renin, and seven had high-renin EHT. DBH, total IU catechols and urinary norepinephrine were not different between these renin subgroups. DBH was significantly lower in all hypertensives (55.6 +/- 36 IU) and in the low-renin subgroup (46 +/- 30 IU) compared with normal subjects (68 +/- 35 IU) (p less than 0.01). However, the DBH range was so broad that an individual DBH value did not distinguish EHT from normals. After a baseline period, patients were randomly assigned to receive chlorthali done 50 mg q.a.m. or placebo in a double-blind study. In the chlorthalidone group 1 month after therapy, the diastolic pressure decreased, PRA increased, and total IU catechols and urinary norepinephrine increased. Serum DBH did not change during diuretic therapy. A significant correlation could not be shown between pretreatment DBH and the changes in PRA and IU catechols before and after diuretics for all treated EHT patients. However, within the normal PRA EHT subgroup receiving chlorthalidone, the one-third of patients with lowest pretreatment DBH levels (n = 10) were compared with the one-third of patients with the highest pretreatment DBH values (n = 10). The lower DBH patients showed significantly less change in PRA (delta PRA = 2.9 +/- 1.8 ng/ml/hr) compared with the higher DBH patients (delta PRA = 8.2 +/- 1.6; P less than 0.05). In some EHT patients, DBH levels may be related to PRA response to diuretic therapy.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
107 patients have been operated upon for atherosclerotic or fibromuscular renal artery stenosis from January 1, 1962 through December 31, 1973. At the time of last follow-up, or at 1 year 67% of patients with atherosclerotic renal artery stenosis, and 79% of patients with fibromuscular renal artery disease were considered to be improved. More recently 50 patients have been treated by surgery (24 patients) or with antihypertensive drugs. 70% (17 of 24) surgically treated patients and 61% (16 of 26) medically treated patients were improved after an average of approximately 1.5 years follow-up.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.