Interaction of nonsteroidal anti-inflammatory drugs with antihypertensive and diuretic agents. Control of vascular reactivity by endogenous prostanoids

The different patterns of blood pressure elevation by rofecoxib and nabumetone

Hypertension and knee osteoarthritis (OA) are frequent comorbidities. Nonsteroidal anti-inflammatory drugs (NSAIDs) are often used to relieve pain in such patients. In the last decade selective NSAIDs are used more commonly since they lead to less gastrointestinal complications. As has been shown, the treatment with NSAIDs may cause a mild rise of arterial blood pressure (BP). The influence of selective NSAIDs on BP, particularly in hypertensive patients has still to be investigated. The aim of this study was to determine arterial BP changes in patients suffering from stable arterial hypertension and knee OA and treated with rofecoxib or nabumetone. Two groups of patients with knee OA and stable arterial hypertension received either 25 mg rofecoxib once daily or namebutone 2000 mg once daily during the first week of treatment and 1000 mg for the following 3 weeks. Twenty-four hour arterial BP monitoring was performed prior to initiation of treatment and at the end of a 4-week period. The results were that no changes were found in the mean systolic and diastolic characteristics of BP in the rofecoxib treatment group during day time (delta systolic BP -0.4 mm Hg and delta diastolic BP -0.4 mm Hg), while nocturnal BP increased significantly: delta systolic BP +15.7 mm Hg and delta diastolic BP +8.5 mm Hg. The mean systolic arterial pressure in the nabumeton group raised delta systolic BP 2.9 mm Hg in the daytime and 5 mm Hg during the night-time after the treatment. The mean diastolic arterial pressure also rose delta diastolic 3.2 mm Hg and 4.9 mm Hg at day and night hours respectively. In conclusion rofecoxib treatment did not change arterial BP during day time hours, however, there was a distinct increase in night-time systolic and diastolic BP leading to a disappearance of the physiological diurnal variation. Nabumetone caused a moderate increase of day and night BP, without changes in biological diurnal variation.

Effect of indomethacin on the antihypertensive efficacy of valsartan and lisinopril: a multicentre study

OBJECTIVE

To compare the effect on antihypertensive efficacy produced by the addition of indomethacin to the angiotensin II (Ang II) antagonist, valsartan, or to the angiotensin-converting enzyme inhibitor, lisinopril, in hypertensive patients with chronic osteoarthritis.

SUBJECTS AND METHODS

One hundred and twenty-eight patients (52 men and 76 women) aged 25-82 years (mean age 55.7 years), with diastolic blood pressure (DBP) > 100 mmHg at the end of a 2-week placebo washout period were allocated randomly to groups to receive valsartan (80-160 mg once daily) or lisinopril (10-20 mg once daily). At the end of 10 weeks of treatment, patients with DBP < 90 mmHg, while continuing to receive valsartan or lisinopril treatment, were allocated randomly to groups to receive either indomethacin (50 mg three times a day) or the corresponding placebo for 2 weeks, with a 1-week washout period between the two treatments, according to a double-blind, crossover design. After the initial washout period, patients were examined at the end of the 4th, 8th and 10th weeks of randomized treatment with valsartan and lisinopril, at the end of the first crossover period and then at the beginning and at the end of the second crossover period. At each visit, sitting and standing blood pressure were measured by standard mercury sphygmomanometer.

RESULTS

The addition of indomethacin blunted the blood pressure-decreasing effect of both antihypertensive drugs. Although indomethacin produced greater increases in both systolic and DBP values in the lisinopril-treated patients (5.45/3.22 mmHg) than in the valsartan-treated ones (2.12/1.87 mmHg), no significant difference between the two drugs was found.

CONCLUSIONS

From a theoretical standpoint, these findings suggest that prostaglandins may play a part in the antihypertensive action of Ang II antagonists. From a practical standpoint, hypertensive patients treated with valsartan or with lisinopril should be monitored to detect changes in blood pressure control while receiving indomethacin.

Controversies in heart failure. Are beneficial effects of angiotensin-converting enzyme inhibitors attenuated by aspirin in patients with heart failure?

To whatever extent the improvement in symptoms and survival rendered by treatment with ACE inhibitors is attributable to their effects on the circulation and the kidneys, this benefit can be rescinded by concomitant administration of aspirin. Although some useful prostaglandin-independent actions may persist, shutting down the entire prostaglandin system and trading off a substantial portion of the potential risk reduction with forfeit of salutary hemodynamic and renal effects is a high price to pay just to suppress production of TXA2. In patients requiring treatment for heart failure, if possible, aspirin should be avoided and the integrity of prostaglandin metabolism respected; the severer the heart failure the more compelling. There are other ways to inhibit platelet aggregation, some equally effective or even better than aspirin. Orally active platelet glycoprotein IIb/IIIa receptor antagonists, which may be more efficient than aspirin, have been developed and are now in clinical testing. Ticlopidine and clopidogrel, although more expensive than aspirin, are as easy to use and at least as effective as aspirin. Finally, because patients with severer heart failure are likely to be those with very low ejection fractions, these patients are good candidates for oral anticoagulation even though this treatment requires additional monitoring.

Effect of indomethacin on blood pressure in elderly people with essential hypertension well controlled on amlodipine or enalapril

Arthritis and hypertension are frequent comorbidities in the elderly hypertensive population. Nonsteroidal anti-inflammatory drugs are often used to relieve pain in arthritic patients but a side effect is sodium retention and consequent elevation of blood pressure (BP). The effect of dihydropyridine calcium blocking drugs is relatively independent of sodium intake, whereas the angiotensin-converting enzyme (ACE) inhibitors' effects can be blunted by a high-sodium diet. This study compared the effects of indomethacin with placebo in elderly patients with essential hypertension who had been controlled with amlodipine or enalapril. Indomethacin 50 mg twice daily or placebo was administered for 3 weeks in a double-blind crossover study to patients controlled with amlodipine or enalapril. The response was assessed by ambulatory BP measurement. Indomethacin raised BP and lowered pulse rates in patients taking enalapril but had little effect in patients receiving amlodipine. The difference caused by indomethacin between the two groups was 10.1/4.9 mm Hg increase in BP and a 5.6 beats/min fall in pulse in people taking enalapril. Addition of indomethacin to patients taking either drug caused a rise in weight and a fall in plasma renin. It is postulated that the effect is due to inhibition of prostaglandin synthesis, which causes sodium retention. In patients taking amlodipine, the fall in plasma renin ameliorates the effect of sodium retention on BP. In patients taking enalapril, plasma renin falls but this is not translated into an effect because of the blockage of converting enzyme. Thus, the full effect of sodium retention on BP is expressed. In patients treated with indomethacin, fewer patients may respond to ACE inhibitors. However, the major problem is the patient who intermittently takes indomethacin or other nonsteroidal anti-inflammatory drugs, which, if a person is treated by an ACE inhibitor causes BP to go out of control. In such patients amlodipine would appear to be a preferred choice to enalapril.

Pharmacotherapy in congestive heart failure: COX-2 inhibition: a cautionary note in congestive heart failure

NSAIDs have been a mainstay of therapy for rheumatologic diseases for a number of years. Unfortunately, their use was accompanied by sometimes unacceptable gastrointestinal and/or renal side effects. Therefore, safer treatment options were sought. In the process of such a search, selective cyclo-oxygenase-2 inhibitors were identified. Drugs in this class have anti-inflammatory properties similar to NSAIDs and did not produce anywhere near the same pattern of NSAID-related gastrotoxicity. The enthusiasm for this class of drugs would appear, at least on the surface, to be well grounded. However, establishing the renal side effect profile of the selective cyclo-oxygenase-2 inhibitors would appear to be a work in progress. Formal studies with selective cyclo-oxygenase-2 inhibitors have not been conducted in the congestive heart failure population. Information does though exist for other patient cohorts--similarly "prostaglandin-dependent" for their integrity of renal function, such as the elderly and sodium-deplete individual. These data would strongly suggest that the selective cyclo-oxygenase-2 inhibitors could decrease glomerular filtration rate and stimulate salt and water retention, comparable to what occurs with nonselective NSAIDs. To date, no compelling information exists, which supports the notion that differences exist among the currently available selective cyclo-oxygenase-2 inhibitors--celecoxib and--in the potential to negatively impact renal function in this and similarly compromised patient populations. (c)2000 by CHF, Inc.

Angiotensin II in human veins: development of rapid desensitization and effect of indomethacin

1. The present study investigated whether rapid desensitization (tachyphylaxis) develops after exposure of human hand veins to angiotensin (Ang)II and whether pretreatment with indomethacin affects its development. 2. Venoconstrictor responses to increasing (2-256 ng/min) and constant (50 ng/min) doses of AngII and noradrenaline (NA) infusion were obtained in six healthy male subjects using the dorsal hand vein technique. After pretreatment with indomethacin and placebo, venoconstrictor responses to 50 ng/min AngII infusion were obtained in eight healthy male subjects. 3. The maximal mean (+/- SD) venoconstrictor response to NA (obtained with 256 ng/min NA) was 93.1 +/- 4.7%, whereas that to AngII (obtained with doses between 16 and 128 ng/min) was 43.8 +/- 12.2%. Continuous infusion of NA induced constant venoconstriction, whereas the venoconstrictor response to AngII peaked 3 min after the beginning of infusion and, thereafter, was attenuated. 4. Venoconstriction in response to constant AngII infusion after indomethacin pretreatment was significantly larger than that after placebo from 6 to 18 min after the initiation of infusion. 5. These findings show that rapid desensitization to AngII develops in human hand veins and this is compatible with the hypothesis that vasodilator prostaglandins are involved in the development of this desensitization.

Effect of indomethacin on the renal response to angiotensin II receptor blockade in healthy subjects

BACKGROUND

Non-steroidal anti-inflammatory drugs are known to promote sodium retention and to blunt the blood pressure lowering effects of several classes of antihypertensive agents including beta-blockers, diuretics and angiotensin converting enzyme (ACE) inhibitors. The purpose of the present study was to investigate the acute and sustained effects of indomethacin on the renal response to the angiotensin II receptor antagonist valsartan and to the ACE inhibitor enalapril.

METHODS

Twenty normotensive subjects maintained on fixed sodium intake (100 mmol sodium/day) were randomized to receive for one week: valsartan 80 mg o.d., enalapril 20 mg o.d., valsartan 80 mg o.d. + indomethacin 50 mg bid and enalapril 20 mg o.d. + indomethacin 50 mg bid. This single-blind study was designed as a parallel (valsartan vs. enalapril) and cross-over trial (valsartan or enalapril vs. valsartan + indomethacin or enalapril + indomethacin). Renal hemodynamics and urinary electrolyte excretion were measured for six hours after the first and seventh administration of each treatment regimen.

RESULTS

The results show that valsartan and enalapril have comparable renal effects characterized by no change in glomerular filtration rate and significant increases in renal plasma flow and sodium excretion. The valsartan- and enalapril-induced renal vasodilation is not significantly blunted by indomethacin. However, indomethacin similarly abolishes the natriuresis induced by the angiotensin II antagonist and the ACE inhibitor.

CONCLUSIONS

This observation suggests that although angiotensin receptor antagonists do not affect prostaglandin metabolism, the administration of a non-steroidal anti-inflammatory drug blunts the natriuretic response to angiotensin receptor blockade.

The hypertensive dental patient

The dental team plays an integral role in safeguarding the general health of patients. Dental health care workers should be able to recognize risk factors associated with hypertension and counsel patients in an effort to reduce those that are present. In addition, dental professionals should recognize how these risk factors and associated hypertension affect the provision of dental care. This article reviews recent findings and therapies for hypertension, evaluates historically accepted but unsupported anecdotal information on the dental management of hypertensive patients and proposes guidelines for the dental management of these patients.

The effect of tenidap on the anti-hypertensive efficacy of thiazide diuretics in patients treated for mild to moderate hypertension

1. This randomised, placebo-controlled, double-blind, parallel-group study was conducted to assess the effect of tenidap sodium 120 mg, a novel anti-arthritic cytokine modulating drug, on the hypotensive efficacy of the thiazide diuretics hydrochlorothiazide or bendrofluazide. 2. Twenty-three male and female patients, aged 41-78 years, with mild to moderate, uncomplicated, essential hypertension controlled with thiazide diuretic therapy, received either a single daily dose of tenidap sodium 120 mg or matched placebo for 22 days in addition to their diuretic therapy. Changes between baseline and endpoint in supine and standing systolic and diastolic pressures and pulse rate were compared between treatment groups. 3. Daily treatment with tenidap reduced the anti-hypertensive efficacy of the thiazide diuretics. Blood pressure tended to increase marginally and the increase in mean standing diastolic pressure observed with tenidap was significantly greater than the change in the placebo group. All pressures tended to decrease in the placebo group and all endpoint measurements were within 7 mm Hg of baseline in both groups. 4. Treatment-related side effects of mild to moderate severity were reported in two subjects receiving tenidap, but in neither case was treatment discontinued. Two subjects receiving placebo also experienced side effects considered to be treatment-related and both were withdrawn from the study. 5. The results of this study suggest that tenidap may be given to patients treated for mild to moderate essential hypertension controlled with thiazide therapy; however, the patient's blood pressure should be regularly monitored.

Amlodipine and haemodynamic effects of cyclo-oxygenase inhibition

1. The haemodynamic effects of calcium antagonists could depend at least in part on the activity of vasoactive prostanoids. 2. We set out to study the effect of the cyclo-oxygenase inhibitor ibuprofen, 400 mg three times daily for 3 days, by a randomised cross-over study vs placebo in 12 mild to moderate essential hypertensive patients who had been treated for 1 month with amlodipine. 3. Blood pressure, heart rate and vascular resistances in the upper limb (Doppler ultrasound) were measured. Plasma renin activity and urinary aldosterone, as well as indices of renal function, were evaluated. Urinary 2,3-dinor-6-keto-PGF1 alpha and 2,3-dinor-TXB2, as well as 6-keto-PGF1 alpha and TXB2, were measured as indices of systemic and renal PGI2 and TXA2 synthesis. 4. Amlodipine normalised blood pressure and reduced upper limb vascular resistances; it did not affect urinary prostanoid excretion. Short-term combined administration of ibuprofen resulted in, by comparison with placebo, inhibition of systemic PGI2 (-80.5 ng 24 h-1, 95% CI -99.2, -61.4; P < 0.001) and TXA2 (-216.1 ng 24 h-1, 95% CI -276.5, -155.8; P < 0.001), together with an increase in systolic (+7.8 mm Hg, 95% CI +3.1, +12.3; P < 0.01) and diastolic (+3.9 mm Hg, 95% CI +1.2, +6.6; P < 0.01) blood pressure; it had no significant effect on regional vascular resistances (+4.7 mm Hg ml-1 s, 95% CI -5.6, +15.0). Effects of ibuprofen on renal prostanoid synthesis were less marked, and there was no change in indices of renal function or hydro-electrolytic balance.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic and humoral effects of low-dose aspirin in treated and untreated essential hypertensive patients

Aspirin at low doses is used as an inhibitor of platelet aggregation and is frequently administered to essential hypertensive patients with arterial thrombotic complications. However, it is unknown whether aspirin can modify blood pressure values either in treated or untreated hypertensive patients, as described for other non steroidal anti-inflammatory drugs. Thus 30 patients. 10 with mild uncomplicated and untreated essential hypertension, 10 with essential hypertension under chronic treatment with captopril, 50 mg bid, and 10 with essential hypertension under chronic treatment with atenolol, 100 mg oid, received aspirin, 100 mg oid, and the corresponding placebo for one month, according to a double blind randomized cross-over design. At the end of each treatment, blood pressure, heart rate, generated serum thromboxane B2 and urinary excretion of thromboxane B2 and 6 keto prostaglandin F1 alpha and plasma renin activity were measured. Both in treated and untreated essential hypertensive patients, aspirin administration did not affect blood pressure, heart rate and urinary 6 keto prostaglandin F1 alpha, while it significantly reduced serum and urinary excretion of thromboxane B2 and plasma renin activity. In conclusion, while the present data confirm that low doses of aspirin selectively inhibit thromboxane B2 synthesis, they indicate that aspirin at 100 mg oid can be administered to treated and untreated essential hypertensive patients without any harmful effect on blood pressure values.

Assessment of blood pressure during treatment with naproxen or ibuprofen in hypertensive patients treated with hydrochlorothiazide

This study determined the effect of nonsteroidal anti-inflammatory drug (NSAID) administration on blood pressure in hypertensive patients taking hydrochlorothiazide (HCTZ). Ninety-seven patients with mild essential hypertension and a musculoskeletal indication for NSAID use were studied in a three-phase, multi-center, double-blind, randomized, parallel study based in 15 academic and community clinics. Patients served as their own controls. Patients with stable hypertension, not taking antihypertensive or NSAID medications, were treated with HCTZ 50 mg/day. After 4 to 5 weeks of treatment and documented stable blood pressure, naproxen 375 mg twice a day or ibuprofen 800 mg three times a day was added. Blood pressure was measured at 2 and 4 weeks of NSAID therapy. The average diastolic blood pressure was 97.5 +/- 2.4 mm Hg and the average of the mean arterial pressure (MAP) was 116.8 +/- 6.04 before treatment with HCTZ. Hydrochlorothiazide treatment decreased diastolic blood pressure to 83.1 +/- 5.6 mm Hg, and MAP to 101.1 +/- 6.5 mm Hg. With naproxen or ibuprofen treatments, mean diastolic blood pressure increased less than 3 mm Hg. At 2 weeks, ibuprofen increased diastolic blood pressure by 2.6 mm Hg (P = .004) and naproxen increased diastolic blood pressure 0.7 mm Hg (P = .40). Both ibuprofen and naproxen significantly increased diastolic pressure at 4 weeks (2.1 mm Hg, P = .042; and 1.8 mm Hg, P = .043, respectively). There was no correlation between the pre-NSAID blood pressure and the magnitude of change after 2 or 4 weeks of treatment. Changes in MAP reflected a pattern similar to diastolic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Counteraction of the vasodilator effects of enalapril by aspirin in severe heart failure

OBJECTIVES

This study was undertaken to determine if a standard dose of aspirin interacts relevantly with the circulatory effects of enalapril in severe heart failure.

BACKGROUND

The frequent association of heart failure with coronary artery disease confers potential for combined treatment with an angiotensin-converting enzyme inhibitor and the prostaglandin synthesis inhibitor aspirin, the pharmacodynamic actions of which are, in part, mutually opposed.

METHODS

In 18 patients, on 3 consecutive days, hemodynamic measurements were performed at baseline and 4 h after administration of a double placebo, enalapril (10 mg) plus placebo and enalapril plus aspirin (350 mg) according to a double-blind, randomized, crossover protocol.

RESULTS

Enalapril given before aspirin led to significant decreases in systemic vascular resistance, left ventricular filling pressure and total pulmonary resistance together with a significant increase in cardiac output. When given with or on the day after aspirin, enalapril did not elicit significant changes in any of these variables. There was a clear tendency to lower values for pulmonary artery pressure on all regimens, and slowing of the heart rate was incurred whether or not aspirin had been given. Chi-square analysis of the individual responses showed that the probability of effecting a decrease in systemic vascular resistance > or = 300 dynes.s.cm-5 was six times greater when enalapril was given without aspirin (p < 0.01).

CONCLUSIONS

In severe heart failure, the prostaglandin synthesis inhibition by aspirin counteracts the systemic arterial vasodilation of angiotensin-converting enzyme inhibition with enalapril and substantiates its dependence on the integrity of prostaglandin metabolism. Trends toward reductions of pulmonary artery pressure and slowing of the heart rate were still observed, presumably subsequent to lowered norepinephrine concentrations indicating maintenance of prostaglandin-independent actions of angiotensin-converting enzyme inhibition.

Nonsteroidal anti-inflammatory drugs and antihypertensives

Approximately 60 million people in the United States have hypertension (BP greater than or equal to 140/90 mm Hg), 40 million have arthritis clinically suitable for nonsteroidal anti-inflammatory drug (NSAID) therapy, and millions take NSAIDs for nonarthritic conditions, creating considerable potential for concomitant administration of NSAIDs and antihypertensive agents. It is estimated that more than 20 million people are on concurrent therapy. Most NSAIDs produce mild elevations of normal blood pressure levels and can partially or completely antagonize the effects of many antihypertensive drugs. The effect on blood pressure can vary from no effect to hypertensive crisis. In pooled studies, the average increase in mean arterial pressure was 10 mm Hg, and duration was short-lived or chronic. Significant interactions occur in about 1% of patients per year. The risk is greatest in the elderly, blacks, and patients with low-renin hypertension. NSAIDs may block the antihypertensive effects of thiazide and loop diuretics, beta-adrenergic blockers, alpha-adrenergic blockers, and angiotensin-converting enzyme inhibitors. No interactions have been reported with centrally acting alpha agonists or the calcium channel blockers. The mechanism of the hypertensive effects of NSAIDs seem primarily related to their ability to block the cyclo-oxygenase pathway of arachidonic acid metabolism, with a resultant decrease in prostaglandin formation. The prostaglandins are important in normal modulation of renal and systemic vascular dilatation, glomerular filtration, tubular secretion of salt and water, adrenergic neurotransmission, and the renin-angiotensin-aldosterone system. Blockade of salutary effects of prostaglandins by NSAIDs results in a complex series of events culminating in attenuation of the effects of many antihypertensive agents. High-risk patients treated with NSAIDs should be identified and have blood pressure, renal function, and serum potassium frequently monitored.

Cardiovascular effects of a chlorpheniramine/paracetamol combination in hypertensive patients who were sensitive to the pressor effect of pseudoephedrine

Twelve hypertensive patients who were classified as pseudoephedrine-sensitive in a preliminary trial were selected for further investigation with single doses of pseudoephedrine 60 mg, a combination of chlorpheniramine 4 mg with paracetamol 650 mg and placebo. A double-blind, randomised, crossover study design was followed. Treatment with pseudoephedrine produced significant effects on all the four variables measured (systolic, diastolic and mean arterial blood pressure, and heart rate). Effects of the chlorpheniramine/paracetamol combination were found to be not significantly different from placebo. It was concluded that the combination may be useful as a medication for 'colds' in hypertensive patients, since it does not induce cardiovascular effects such as those observed with pseudoephedrine.

Differential inhibitory potencies of non-steroidal antiinflammatory drugs on smooth muscle prostanoid synthesis

In isolated rat aorta and urinary bladder, indomethacin inhibited the synthesis of the prostaglandins (PG) PGI2, PGE2, PGF2 alpha and TXA2 equipotently when PG synthesis was stimulated with excitatory receptor agonists (noradrenaline and carbachol), fluoride (a G protein activator), phorbol ester (a protein kinase C (PKC) activator) and calcium ionophore A23187 (a creator of artificial calcium channels). However, there was a marked right shift (30 fold) in the indomethacin concentration-inhibition curves when PG synthesis was stimulated by arachidonate (PG substrate) and trauma (freeze fracturing and sonication). Although less potent than indomethacin, the NSAIDs tiaprofenic acid and ibuprofen showed a similar disparity between the IC50s with the same PG stimulators. Since PG synthesis stimulated by receptor agonists, fluoride, phorbol ester and A23187 is dependent on calcium channel activation whereas trauma and arachidonate-stimulated PG synthesis bypass calcium channel activation, these data indicate that NSAIDs inhibit not only cyclooxygenase but also (and more potently) the mobilisation of Ca2+ linked to PG synthesis in these tissues.

Lack of interaction between sulindac or naproxen and propranolol in hypertensive patients

Seventeen patients with hypertension and osteoarthritis participated in a single-blind crossover study comparing the effects of sulindac 200 mg twice daily, naproxen 500 mg twice daily, and placebo on blood pressure. All patients were treated for hypertension with propranolol monotherapy. Blood pressures were back-titrated to achieve a baseline diastolic blood pressure of 90 to 100 mm Hg while taking naproxen. There were no significant differences in mean sitting or standing blood pressures among the patients receiving naproxen, sulindac, or placebo treatments. There was no change in pulse, weight, or any of the laboratory measurements at the end of each treatment phase. These results suggest that neither sulindac nor naproxen interferes with propranolol therapy for uncomplicated hypertension.

Propranolol increases prostacyclin synthesis in patients with essential hypertension

We tested the hypothesis that vascular prostacyclin synthesis is increased by propranolol and could account for some of the drug's antihypertensive effect. We studied 10 white patients with mild essential hypertension in a randomized, double-blind design to assess the effects of indomethacin with or without the addition of propranolol on blood pressure and vascular prostacyclin biosynthesis, as assessed by the urinary excretion of the major enzymatically produced metabolite of prostacyclin, 2,3-dinor-6-keto-prostaglandin F1 alpha (PGF1 alpha), F1 alpha (PGF1 alpha), measured by gas chromatography-mass spectrometry. Seven patients responded to propranolol with a lowering of mean arterial blood pressure in both supine and upright postures. The fall in mean arterial blood pressure (-14.1 +/- 2.1 mm Hg sitting; -17.4 +/- 1.7 mm Hg supine) with propranolol alone was significantly greater than that produced when propranolol was given to patients receiving indomethacin (-7.8 +/- 1.9 mm Hg sitting; -7.7 +/- 3.0 mm Hg supine). Our drug-responsive patients demonstrated a significantly lower excretion rate of 2,3-dinor-6-keto-PGF1 alpha than was found in an age and sex-matched group of normal volunteers. With propranolol treatment, drug-responsive patients showed a significant increase in the excretion of 2,3-dinor-6-keto-PGF1 alpha, such that the mean excretion was not significantly different from that in normal volunteers. Indomethacin caused a significant rise in mean arterial blood pressure and a significant fall in 2,3-dinor-6-keto-PGF1 alpha excretion, and it blocked the rise in urinary 2,3-dinor-6-keto-PGF1 alpha associated with propranolol therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Preserved renal perfusion during beta blockade by tertatolol with and without cyclooxygenase inhibition in normal humans

The systemic and renal hemodynamic effects of tertatolol, a new noncardioselective beta blocker without partial agonist activity, given alone or in combination with cyclooxygenase inhibition by acetylsalicylic acid (aspirin), were investigated in eight healthy volunteers. Tertatolol 5 mg, aspirin 1 g, tertatolol 5 mg together with aspirin 1 g and placebo were administered at 1-week intervals in a random order and in a double-blind fashion. Cardiac output was measured by Doppler echography and renal blood flow and glomerular filtration rate (GFR) by constant infusion techniques using (123I) iodohippurate and (51Cr) EDTA, respectively. Measurements were performed before and then successively 2 and 4 hours after oral intake of drugs or placebo. Tertatolol decreased cardiac output by 22% (P less than .05) and heart rate by 17% (P less than .05) without change in blood pressure, renal blood flow, and GFR. The same effects occurred when tertatolol was given together with aspirin. Either placebo or aspirin alone had no effect on systemic and renal hemodynamics. These results suggest that cardiac output is redistributed to the kidneys after tertatolol intake in normal humans. This favorable effect on renal hemodynamics is probably not mediated by a local release of vasodilating prostaglandins.