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Biomedical subjects

C S Wilcox

Publications and source records attributed to C S Wilcox.

At least 73 records · Page 4Linked to original sources
PubMed1996

Nefazodone versus sertraline in outpatients with major depression: focus on efficacy, tolerability, and effects on sexual function and satisfaction.

BACKGROUND: The efficacy, tolerability, and effects on sexual function and satisfaction of nefazodone and sertraline were compared in a multicenter, randomized, double-blind, parallel-group study in outpatients with major depression. METHOD: One hundred sixty patients, 18 years of age or older, who met DSM-III-R criteria for single or recurrent nonpsychotic major depressive episodes were randomly assigned to 6 weeks of treatment with either nefazodone (100-600 mg/day) or sertraline (50-200 mg/day). Symptoms were assessed before and during treatment using the 17-item Hamilton Rating Scale for Depression (HAM-D-17), Clinical Global Impressions (CGI) Improvement scale, the CGI Severity of Illness scale, and a sexual function questionnaire. RESULTS: Of 143 patients evaluable for efficacy, 72 received sertraline and 71 received nefazodone. The mean modal daily dose at endpoint was 148 mg for sertraline and 456 mg for nefazodone. Analysis of efficacy measures (HAM-D-17 and CGI) showed consistent and comparable improvement in symptoms of depression for both treatment groups. Sertraline had negative effects on sexual function and satisfaction in both men and women, and nefazodone had no adverse effect on sexual well-being. Safety assessments based on adverse events, vital sign measurements, electrocardiographs, physical examinations, and clinical laboratory tests revealed no serious adverse events or organ toxicity associated with nefazodone or sertraline administration. CONCLUSION: Nefazodone and sertraline are well tolerated, and there was no statistically significant difference in their antidepressant activity. Sertraline treatment has negative effects on sexual function and performance in both sexes, while nefazodone has none. These findings may have clinical implications when choosing antidepressant therapy.

1-Naphthylamine↗
PubMed1996

Ischemic nephropathy: noninvasive testing.

Ischemic nephropathy is defined as hypertension and a defect in renal function and/or loss of renal parenchyma caused by hemodynamic changes secondary to a renal artery stenosis. A work-up should be reserved for those patients considered candidates for intervention with percutaneous transluminal renal angioplasty (PTRA) or reconstructive surgery in whom there is hypertension with clinical features suggestive of ischemic nephropathy and/or a significant size disparity between the kidneys. Therefore, all patients suspected of ischemic nephropathy should undergo a renal ultrasound examination to quantitate renal size and a test of overall renal function (creatinine clearance or DTPA plasma disappearance). The diagnostic accuracy of functional tests for renovascular hypertension can be seriously impaired in the presence of renal insufficiency, and they have not been evaluated systematically in this clinical setting. Therefore, tests are reserved for those patients in whom the clinical clues of ischemic nephropathy are equivocal. Available evidence suggests that angiotensin-converting enzyme inhibitor (ACEI)-induced changes in the Hippuran or Mag3 renogram are predictive of reversible renovascular hypertension in the presence of renal insufficiency. Duplex ultrasound scanning of the renal arteries is an accurate method to identify renal artery stenosis in experienced hands. However, there is no quantitative information to judge the utility of noninvasive tests in predicting which patients with ischemic nephropathy will have an improvement in renal function after intervention.

Animals↗
PubMed1996

TGF and nitric oxide: effects of salt intake and salt-sensitive hypertension.

The tubuloglomerular feedback response (TGF) entails vasoconstriction of the afferent arteriole (AA) and a fall in the glomerular capillary pressure (PGC) and single nephron glomerular filtration rate (SNGFR) during NaCl reabsorption in the macula densa (MD) segment. Recent studies have concluded that nitric oxide (NO) is synthesized by the MD and blunts the TGF response. Since a high salt (HS) diet has been found to blunt TGF, we tested the effects of salt intake on the response to blockade of nitric oxide synthesis. For the first series, the TGF was assessed from changes in proximal stop-flow pressure (PSF, an index of PGC in response to graded perfusion of the loop of Henle (LH) with name tubular fluid (NTF). Loop perfusion with 10(-3) M L-NMA did not affect the PSF responses of low salt (LS) rats, but reduced (P < 0.01) the PSF of HS rats during perfusion at 20 nl.min-1 (-1.5 +/- 0.4 mm Hg; P < 0.01) and at 40 nl.ml-1 (-2.2 +/- 0.5 mm Hg; P < 0.001). For the second series, the TGF responses of salt sensitive Dahl/Rapp (ssDR) rats were compared to Sprague-Dawley (SD) rats. Both groups were studied 8 to 10 days after starting HS or LS diets by loop perfusion of artificial tubular fluid at 40 nl.min-1. Compared to Sprague-Dawley rats, the ssDR had blunted maximal TGF responses during LS (SD, 8.2 +/- 0.3 vs. ssDR, 6.4 +/- 0.3 mm Hg; P < 0.001), but not during HS. During LS intake, addition of L-NMA to ATF perfusing the loop of Henle did not alter the maximal TGF response of either strain. However, during HS intake L-NMA increased the maximal TGF response of SD rats (4.4 +/- 0.4 to 6.7 +/- 0.5 mm Hg; P < 0.001) but did not significantly change the PSF of ssDR rats (5.2 +/- 0.3 to 5.7 +/- 0.5 mm Hg; NS). We conclude that the TGF response is enhanced by blockade of NOS during HS, but not LS intakes; this response to NOS blockade during HS intake is lost in salt sensitive Dahl/Rapp rats.

Animals↗
PubMed1996

Increasing ethnic diversity and managed care: how will they influence research patient recruitment in the nineties?

The challenge of research patient recruitment is intensifying in the 1990s. Relevant factors include the often negative impact of the press, increasing competition for patients, an increasingly ethnically diverse population, and a pervasive trend toward managed care. Based on preliminary findings from a patient focus group, 550 patients were contacted by mail and asked to complete a 25-item questionnaire. Survey results indicate that for most study patients initial telephone contact with a health care professional is not as important as the perception of a genuinely caring (i.e., "non-guinea pig") environment. Office location and other intangibles also affect recruitment; furthermore, several of the benefits sought by volunteers transcend ethnicity. The trend toward managed care will not impede and may enhance research patient recruitment. This research provides information and data that will enable investigators and sponsors to better meet the challenges of patient recruitment in the 1990s.

Adult↗
PubMed1996

Fluid homeostasis after heart transplantation: the role of cardiac denervation.

BACKGROUND: Orthotopic heart transplantation may interrupt key neural and humoral homeostatic mechanisms that normally adjust Na+ and fluid excretion to changes in intake. Such an interruption could lead to plasma volume expansion. METHODS: We measured plasma volume and fluid regulatory hormones under standardized conditions in 11 heart transplant recipients (58 +/- 7 years old; mean +/- standard deviation) 21 +/- 4 months after transplantation, in 6 liver transplant recipients (51 +/- 6 years old) 13 +/- 8 months after transplantation (cyclosporine control group), and in 7 normal healthy control subjects (61 +/- 9 years old). Administration of all diuretics and antihypertensive drugs was discontinued before the study. After 3 days during which subjects ate a constant diet containing 87 mEq of Na+ per 24 hours, plasma volume was measured by a modified Evans blue dye (T-1824) dilution technique. Renal creatinine clearance was measured and blood samples were drawn for determination of plasma levels of vasopressin, angiotensin II, aldosterone, atrial natriuretic peptide, and plasma renin activity. RESULTS: Supine resting plasma renin activity, angiotensin II, and aldosterone (renin-angiotensin-aldosterone axis) and vasopressin levels were not different among the control, heart transplant, and liver transplant groups. However, there was a trend toward elevated angiotensin II (p < or = 0.08) and aldosterone (p < or = 0.08) levels in the heart transplant recipients. Atrial natriuretic peptide levels were significantly elevated two to threefold in the heart transplant recipients when compared with those in the two control groups. Blood volume, normalized for body weight (milliliters per kilogram), was significantly greater (14%) in the heart transplant recipients when compared with that in liver transplant recipients and normal healthy control subjects. Blood volume values did not differ (p > or = 0.05) between the two control groups. CONCLUSIONS: Extracellular fluid volume expansion (+14%) occurs in clinically stable heart transplant recipients who become hypertensive. Although hyperactivity of the renin-angiotensin-aldosterone axis is not apparent during supine resting conditions, our data suggest that the renin-angiotensin-aldosterone system is not responsive to a hypervolemic stimulus and this is likely a consequence of chronic cardiac deafferentation. Thus, poor adaptation of the renin-angiotensin-aldosterone system to fluid retention may be partly responsible for the incidence and severity of posttransplantation hypertension in some heart transplant recipients.

Aged↗
PubMed1996

A double-blind trial of low- and high-dose ranges of gepirone-ER compared with placebo in the treatment of depressed outpatients.

We report the results of a double-blind study comparing the efficacy and safety of low-dose (10-50 mg) and high-dose (20-100 mg) ranges of gepirone-extended release (ER) and placebo in 145 outpatients with major depressive disorder. At multiple time points and endpoint (Week 6), statistically significant reductions in Hamilton Rating Scale for Depression (HAM-D) scores were recorded for high-dose gepirone-ER compared to placebo. Analysis of the 17-item HAM-D and 28-item HAM-D scores indicated a relatively early onset of antidepressant efficacy with statistically significant results at treatment Weeks 1, 2, 4, and 6. A rapid response was evident in the high-dose group, beginning at Week 1 (p < .05). The most frequently reported adverse experiences were headache, nausea, dizziness, and insomnia. The results indicate that gepirone-ER is clearly superior to placebo in terms of antidepressant efficacy. When used at higher doses, gepirone-ER appears to be efficacious, safe, and well-tolerated in depressed out-patients.

Adolescent↗
PubMed1995

Thromboxane synthase expression in renal transplant patients with rejection.

Thromboxane synthase (TS) catalyzes the formation of thromboxane (TxA2) in monocytes/macrophages, platelets, and various tissues. TxA2 is likely to play a role in graft dysfunction due to its vasoconstrictive and platelet aggregatory properties. We studied the expression of TS in 7 normal native kidneys, 29 consecutive renal allograft biopsies (performed for rising serum creatinine, n = 23, and delayed graft function, n = 6), and one transplant nephrectomy specimen with severe acute rejection. TS expression was determined by immunocytochemistry using a monoclonal antibody against human TS, Kon-7. Histologic grading of the transplant biopsy specimens was based on the Banff classification. The degree of TS staining was graded in the glomeruli, interstitium, tubules and vessels from 0 to 3+. Of 29 biopsies, 13 had chronic nephropathy (CN), 6 had acute rejection (AR) with chronic nephropathy (AR/CN), 4 had acute rejection (AR), and 6 had acute tubular necrosis (ATN). TS staining of native kidneys showed sporadic interstitial cells. The biopsy and transplant nephrectomy specimens showed significant staining, predominantly in the glomeruli and interstitium. Positively staining cells appeared to be of macrophage/monocyte lineage by morphology. The mean glomerular staining grade was significantly increased in specimens with AR (2.3 +/- 0.9) and the mean interstitial staining was increased in specimens with AR/CN (2.2 +/- 0.9). Follow-up renal function 6 months post-biopsy showed that patients with higher TS staining grades had a faster decline in graft function. In conclusion, TS expression is increased in patients with acute rejection with or without chronic nephropathy and is associated with more rapid deterioration in function.

Adult↗
PubMed1995

A double-blind, placebo-controlled study of a CCK-B receptor antagonist, CI-988, in patients with generalized anxiety disorder.

This multicenter, double-blind, placebo-controlled, parallel-group, randomized study assessed the efficacy, safety, and tolerability of a novel CCK-B antagonist CI-988 in the treatment of generalized anxiety disorder (GAD). Patients received placebo or CI-988 (300 mg/day, thrice daily) for 4 weeks. Patients with a primary diagnosis of GAD according to DSM-III-R criteria were randomized. The study design included a 1- to 2-week single-blind placebo baseline phase, followed by a 4-week double-blind treatment phase. Efficacy was measured weekly by Hamilton Rating Scale for Anxiety (HAM-A), Clinical Global Impressions of Severity and Change, UCLA-Multi Dimensional Anxiety Scale, and Hamilton Rating Scale for Depression. Patients were also evaluated to determine whether they met criteria for irritable bowel syndrome (IBS) at screening and were evaluated with a gastrointestinal visual analog scale at each visit. Eighty-eight patients were randomized to CI-988 (N = 45) and placebo (N = 43) at three centers. CI-988 did not demonstrate an anxiolytic effect superior to placebo in this clinical trial. There was no significant difference in mean change in HAM-A total between placebo (-7.73) and CI-988 (-8.64). However, a significant treatment-by-center interaction and a highly variable placebo response rate among the three centers limit the interpretation of the results. CI-988 did not have an effect on symptoms of IBS other than diarrhea, which worsened in patients with IBS. Other than a higher incidence of some gastrointestinal symptoms (diarrhea, dyspepsia, flatulence, and nausea), CI-988 was well tolerated. Results suggest that testing higher oral doses of CI-988 may be warranted.

Adult↗
PubMed1995

Comparison of the effects on pupil size and accommodation of three regimens of topical dapiprazole.

BACKGROUND: Patients who have their pupils dilated for an eye examination traditionally have to wait several hours before their pupils return to normal size and their blurred vision (caused by paralysis of accommodation) resolves. Earlier studies with dapiprazole have demonstrated an accelerated reversal of dilatation. METHODS: Three regimens of dapiprazole were studied to determine the effects on pupil diameter and accommodation after mydriasis produced by 2.5% phenylephrine and 0.5% tropicamide. Test regimens included one drop and 1 + 1 drop regimens, compared with a 2 + 2 drop reference regimen. Dapiprazole was administered in one eye and placebo in the other. Mean change from baseline was analysed for pupil diameter and accommodation at various time points after drug administration. Also, for the same variables, 90% confidence intervals for the areas under the curve (AUC) were computed. RESULTS: Both test regimens were equivalent to the reference regimen on the basis of mean change from baseline for pupil diameter and accommodation at individual time points, and for the mean AUC. Most signs and symptoms (injection, stinging, burning, lid oedema, and ptosis) were less frequent in the test regimen treated eyes. There was no significant interaction between regimen and eye colour. CONCLUSION: This study indicates that a lower dosage (for example, one drop) is also efficacious and has the added benefit of fewer side effects.

Accommodation, Ocular↗
PubMed1995

Validation of miniature ultrasonic transit-time flow probes for measurement of renal blood flow in rats.

This study validates the accuracy of miniature ultrasonic transit-time flow probes for measuring renal blood flow (RBF) in the rat. Probes for 1-mm and 2-mm vessels were calibrated ex vivo using excised arteries at varying flow rates and hematocrit (Hct). Correlation between measured and true flow rates for the 2-mm probe were identical (r = 1.0) at both normal and subnormal Hct values. Correlation for the 1-mm probe was high (r = 0.994) at normal Hct, but varied at both high flow rates and subnormal Hct values. In vivo correlation of RBF measurements using the 1-mm probe with the clearance and extraction of p-aminohippuric acid showed a high correlation (r = 0.84; n = 72, P < 0.0001) over a wide range of flow rates (0.5-21 ml/min) and Hct (36-74%). Zero flow levels remained steady, averaging -0.2 +/- 0.2 ml/min during occlusion in the living animal and -0.1 +/- 0.3 ml/min after exsanguination. This study shows that the ultrasonic transit-time flowmeter (1-mm and 2-mm probes) is a reasonably accurate and reliable method with which to measure RBF in the anesthetized, acute-instrumented rat.

Animals↗
PubMed1995

Renal vasodilation with L-arginine. Effects of dietary salt.

Infusion of L-arginine, the substrate for nitric oxide synthase, causes renal vasodilation. Since dietary salt restriction blunts the renal vasoconstrictor response to inhibition of nitric oxide synthase, we investigated the hypothesis that dietary salt intake determines the renal vascular response to L-arginine. Bolus intravenous doses of L-arginine given to anesthetized Sprague-Dawley rats caused dose-dependent increases in renal blood flow and decreases in renal vascular resistance, whereas D-arginine was not effective. The response to L-arginine was prevented by pretreatment with NG-nitro-L-arginine methyl ester. Compared with rats adapted to a high salt diet, those adapted to a low salt diet were more sensitive to the reductions in blood pressure and renal vascular resistance (threshold dose of L-arginine for renal vascular resistance: low salt, 2.9 +/- 0.9 mumol . kg-1 versus high salt, 20.0 +/- 6.2; P < .025), but the maximal changes in renal vascular resistance were similar (low salt, -43 +/- 5% versus high salt, -34 +/- 5%; P = NS). Bolus doses of L-glycine also caused dose-dependent renal vasodilation, but the renal vasodilator responses were not affected by salt intake. Preinfusion of L-arginine augmented the renal vasoconstrictor response to NG-nitro-L-arginine methyl ester in low salt but not high salt rats; after L-arginine dietary salt no longer significantly affected the renal vasoconstrictor response to NG-nitro-L-arginine methyl ester. In conclusion, renal vasodilation is more sensitive to L-arginine during salt restriction. This effect is specific for L-arginine.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Expression of immunoreactive nitric oxide synthase isoforms in rat kidney. Effects of dietary salt and losartan.

Immunohistochemical studies have shown expression of two different isoforms of NOS in the juxtaglomerular apparatus (JGA). Antibodies to a Ca(++)-calmodulin dependent isoform purified from rat brain (B-NOS) label the macula densa cells whereas antibodies to an isoform purified from rat aortic smooth muscle cells in culture (VSM-NOS) induced with lipopolysaccharide and interferon gamma label the afferent arteriole. Since dietary salt intake and angiotensin II (Ang II) are determinants of renal NO generation, we have tested the hypothesis that salt intake can regulate the immunohistochemical expression of these NOS isoforms through an effect of Ang II. In 4 of 5 paired studies, the immunostaining for both B-NOS and VSM-NOS was more intense in rats that had received a low salt (LS), compared to a high salt (HS), diet. Infusion of the Ang II type 1 (AT1) receptor antagonist, losartan, enhanced the intensity of immunoreactive staining for both isoforms. In conclusion, the immunohistochemical expression of NOS isoforms in the JGA is increased by dietary salt restriction; this effect cannot be ascribed to Ang II acting on type 1 receptors.

Amino Acid Oxidoreductases↗
PubMed1995

Extreme blood pressure fluctuations in a patient with intact autonomic reflexes and intact sodium conservation.

A patient who had episodes of profound hypotension alternating with severe hypertension without an obvious precipitating cause is reported. The hypotensive episodes were accompanied by tiredness, syncope, bradycardia, and a low norepinephrine concentration while supine or standing. In contrast, the hypertensive episodes were associated with marked tachycardia, sweating, anxiety, abdominal pain, and very high levels of plasma norepinephrine concentration. Extensive investigations failed to support a diagnosis of pheochromocytoma. The testing of baroreceptor function and autonomic reflexes was normal. Blood pressure was not salt sensitive. It was concluded that this patient has a unique clinical syndrome of extreme fluctuation of blood pressure and sympathetic nervous activity yet intact cardiovascular reflexes and normal sodium conservation. The abnormal blood pressure regulation most likely has a central origin.

Aged↗
PubMed1994

A fixed-dose study of adinazolam-SR tablets in generalized anxiety disorder.

1. This four-week, randomized, double-blind, multicenter study compared the efficacy and safety of adinazolam-SR, at three dosage levels, with placebo. Forty (40) patients were randomized at our site: 10 to adinazolam 30 mg/day, 10 to 60 mg/day, 10 to 90 mg/day, and 10 to placebo. All patients were moderately anxious with Hamilton Anxiety Scale (HAM-A) scores of > or = 21 at baseline. 2. The data were analyzed by pooling the three adinazolam groups and comparing them with the placebo group using t-tests. HAM-A scores decreased significantly more in the pooled adinazolam-SR treatment group than in the placebo group at both Week one (p < .02) and at Week two (p < .01), as well as at endpoint (p < .03). 3. At endpoint the adinazolam-treated group included 8 "responders" (> or = 50% reduction on the baseline HAM-A score) while none of the placebo patients were responders (p < .05). Dose-response effects were evaluated and relationships were not statistically significant. 4. The results indicate that adinazolam-SR was clearly superior to placebo for the treatment of patients suffering from Generalized Anxiety Disorder.

Adolescent↗
PubMed1994

The simplified captopril test: an effective tool to diagnose renovascular hypertension.

There is much variability among reports of the accuracy of the captopril test for renovascular hypertension. Factors that contribute to this variability include a lack of consistency in diagnostic criteria, the preparation of the patient and the performance of the test, and the criterion standard (renal artery stenosis or renovascular hypertension). We investigated the sensitivity and specificity of a simplified version of the test, based on a single postcaptopril value of plasma renin activity, in 36 patients who were undergoing either angioplasty or surgery for renal artery stenosis. The test demonstrated an excellent sensitivity (96%) but a poor specificity (55%). However, the poor specificity was related to certain clinical characteristics; high baseline plasma renin activity measurements, female gender, current smoking, renal dysfunction, and bilateral renal artery stenosis were all associated with false-positive results. This simplified captopril test, when applied to a population with a high prevalence of renovascular hypertension and performed in a standardized manner, can accurately identify those patients unlikely to respond to intervention. However, a positive test, especially in those with the characteristics noted above, does not help clinical decision making because of the limited test specificity.

Captopril↗
PubMed1994

CO2 digital angiography: a safer contrast agent for renal vascular imaging?

Although the new nonionic contrast agents are safer than ionic agents, renal insufficiency and even death still occur occasionally. Therefore, we have explored the use of carbon dioxide (CO2) as an alternative angiographic contrast agent used in combination with digital subtraction angiography. Clinical observations have been made in over 800 patients. The images obtained are of equivalent diagnostic quality compared with those using conventional iodinated contrast agents. Recent advances in imaging, including "stacking," provide images comparable with iodinated contrast. Very small vessels, equivalent to third-order branches of the renal artery, can be imaged satisfactorily with CO2. Occasional studies with CO2 yield information not apparent with iodinated contrast agents, including excellent visualization of arteriovenous shunts, collateral circulations, malignant tumors, and minute amounts of arterial bleeding. Many of the advantages and disadvantages of CO2 derive from its special physical and chemical properties. The advantages include no allergic potentiation and no renal metabolism of CO2, because CO2 is cleared by the lungs and does not recirculate. Other advantages include delivery by very small catheters because of the low viscosity of CO2, minimal discomfort on injection, and very low cost. However, the low-density and compressibility of CO2 poses some special problems. Imaging requires digital subtraction angiography with electronic enhancement and injections require an experienced investigator and, ideally, a dedicated CO2 injector. The dedicated CO2 injector provides calculated, controlled dosing and rates for injection, while excluding the possibility of air contamination. The buoyancy of CO2 inhibits good filling of dependent vessels. Accordingly, CO2 does not normally produce good nephrographic images, although proximal renal arteries are normally shown clearly. Experimental studies in dogs, whose renal arteries have been injected repeatedly with very large doses of CO2, demonstrate only transient changes in renal blood flow and no endothelial cell damage. However, these studies also showed clearly that renal ischemia can occur due to a "vapor lock" phenomenon if the kidney is positioned vertically above the injection site, and recurrent injections are given without time for absorption of the arterially delivered CO2 boluses. Uncontrolled studies in over 800 patients have confirmed that CO2 likely has a very low renal toxicity. At the University of Florida, CO2 is the radiologic contrast agent of choice in patients with renal insufficiency, especially those with diabetes mellitus, and in those with pre-existing allergy to iodinated contrast agents. Further controlled clinical studies are required to define the true clinical utility and safety of CO2 compared with conventional radiologic contrast agents.

Angiography, Digital Subtraction↗
PubMed1994

Renal vasoconstriction during inhibition of NO synthase: effects of dietary salt.

Since dietary salt loading enhances nitric oxide (NO) generation in the kidney, we investigated the hypothesis that changes in salt intake have specific effects on vascular resistance in the kidney mediated by the L-arginine-NO pathway. We contrasted changes in renal and hindquarter vascular resistances (RVR and HQVR) in anesthetized rats during intravenous infusions of graded doses of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME). Groups (N = 8 to 10) of rats were maintained on a high salt (HS) or low salt (LS) diet for two weeks. Compared to those on LS, rats on HS had a greater increase in mean arterial pressure (delta MAP; +32 +/- 4 vs. +22 +/- 3%; P = 0.05) and RVR (+160 +/- 17 vs. +83 +/- 10%; P < 0.005) and a greater fall in renal blood flow (delta RBF; -47 +/- 3 vs. -32 +/- 4%; P < 0.01); changes in HQVR were similar in the two groups. The enhanced RVR response to L-NAME in HS rats could not be ascribed to the higher renal perfusion pressure (RPP) since it persisted in rats whose RPP was controlled by adjustment of a suprarenal aortic clamp. Changes in RVR with an NO donor (SIN-1) were similar in HS and LS rats. L-NAME reduced plasma renin activity in both HS and LS rats. After inhibition of ACE with captopril, or of angiotensin II type I (AT1) receptor with losartan, the increase in RVR with L-NAME remained greater in HS than LS rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Oxidoreductases↗