pituitrin and Renal-Artery-Obstruction

Topics: Angiotensin II; Animals; Cardiac Output; Cardiomyopathies; Dogs; Hemodynamics; Homeostasis; Humans; Hypertension; Hypertension, Renal; Norepinephrine; Rabbits; Renal Artery Obstruction; Renin-Angiotensin System; Vascular Resistance; Vasopressins

The effects of clonidine on renal hemodynamics and renal function make it a particularly useful antihypertensive agent. During treatment of hypertensive patients with clonidine, renal blood flow and glomerular filtration rate are well maintained, and renin secretion is reduced. Early in therapy, a slight tendency to retain salt and water may be seen as blood pressure is lowered. This effect on salt and water excretion is usually transient and may be avoided if a diuretic is used concomitantly. No deterioration of renal function was noted in patients with primary hypertension who were treated with clonidine for periods from 6 months to at least 5 years. The drug is effective in patients with renal hypertension with or without renal failure and well tolerated. Clonidine is also effective in hypertensive patients undergoing chronic hemodialysis, but doses may have to be reduced because the drug is excreted chiefly by the kidney.

Topics: Adrenal Gland Neoplasms; Aldosterone; Antihypertensive Agents; Catecholamines; Clonidine; Humans; Hypertension; Kidney; Kidney Diseases; Pheochromocytoma; Renal Artery Obstruction; Sympathetic Nervous System; Vasopressins; Water-Electrolyte Balance

Diagnostic approaches evolve steadily. Selective renal arteriography and determination of renal vein renins have replaced differential clearances and translumbar aortography. The hydrated intravenous pyelogram remains helpful in assessing physiologic significance and complements both aortography and renin determinations. Except for young patients, medical treatment rather than surgical management usually is preferred.

Topics: Adult; Creatinine; Dehydration; Female; Humans; Hydrogen-Ion Concentration; Hypertension, Renal; Kidney Function Tests; Middle Aged; Renal Artery Obstruction; Renin; Saline Solution, Hypertonic; Sodium; Sodium Chloride; Urography; Vasopressins; Water-Electrolyte Balance

Topics: Aldosterone; Angiotensin II; Edema; Extracellular Space; Female; Glomerular Filtration Rate; Humans; Hyperaldosteronism; Hypertension; Hypotension; Juxtaglomerular Apparatus; Kidney; Kidney Diseases; Kidney Failure, Chronic; Natriuresis; Potassium; Pregnancy; Pregnancy Complications; Pressoreceptors; Regional Blood Flow; Renal Artery Obstruction; Renin; Vasopressins

Topics: Angiography; Biological Transport, Active; Contrast Media; Dehydration; Diuresis; Furosemide; Glomerular Filtration Rate; Humans; Hypertension; Kidney; Kidney Calculi; Kidney Concentrating Ability; Kidney Failure, Chronic; Kidney Tubules; Male; Metaraminol; Prostatic Diseases; Renal Artery Obstruction; Sodium; Urinary Calculi; Urography; Vasopressins

Assessment of plasma renin activity (PRA) in renal vein blood is used in the diagnosis of unilateral renovascular hypertension (URVH). Recently also other markers of renal ischaemia (atrial natriuretic peptide, adrenalin, nonadrenaline and dopamine) have been described. The present study aimed to assess renal handling of vasopressin (AVP) by the ischaemic kidney in patients with URVH. In 16 patients with URVH, PRA and AVP were estimated in renal vein blood of the ischemic (IK) and non-ischemic kidney (NK), in arterial blood (A) and in blood samples withdrawn from the inferior vena cava (VCI) below the orifices of the renal veins. In contrast to PRA no significant difference between plasma levels of AVP in renal vein blood of the ischaemic and non-ischaemic kidney was noticed (4.8 +/- 0.9 pg/ml vs 5.1 +/- 0.8 pg/ml respectively).. Chronic hypoperfusion of the kidney does not influence renal handling of AVP in patients with URVH. Thus assessment of AVP in renal vein blood in these patients is deprived of diagnostic value.

Topics: Adult; Biomarkers; Female; Humans; Hypertension, Renal; Ischemia; Kidney; Male; Middle Aged; Renal Artery Obstruction; Vasopressins

We have investigated the role of angiotensin II in the development of high blood pressure and in the maintenance of renal function during 2 weeks of one-kidney renal artery stenosis in conscious dogs. Responses to a fixed degree of inflation of a balloon cuff around the renal artery were compared in dogs with or without continuous enalapril (MK 421) treatment. In six untreated dogs, mean aortic pressure was increased by 17.1 +/- 2.0 mm Hg, due primarily to increases in total peripheral resistance with little change in cardiac output, while glomerular filtration rate, renal blood flow, renal artery pressure, and plasma renin activity were back to prestenosis levels. In seven enalapril-treated dogs mean aortic pressure was increased by 23.0 +/- 2.7 mm Hg and was not significantly different from that occurring in untreated dogs. This rise was due to increases in total peripheral resistance (10%) and cardiac output (12%). In the absence of angiotensin II, glomerular filtration rate remained low, at only 56 +/- 6% of prestenosis levels. Renal blood flow returned to normal, but the renal artery pressure remained 25% lower than control values. Thus, the main role of angiotensin II in chronic one-kidney Goldblatt hypertension does not appear to be through its pressor properties but rather through its actions in the kidney to preserve glomerular filtration. This effect on renal function persisted throughout the course of the hypertension, even when the plasma renin levels returned to normal.

Topics: Angiotensin II; Animals; Blood Pressure; Cardiac Output; Dogs; Enalapril; Glomerular Filtration Rate; Hypertension, Renovascular; Kidney; Male; Renal Artery; Renal Artery Obstruction; Renin; Vascular Resistance; Vasopressins; Water-Electrolyte Balance

Male Sprague-Dawley rats with unilateral renal artery stenosis and a contralateral untouched kidney develop a malignant hypertension (MH) which is characterized by high blood pressures, sodium and water depletion, and subsequent activation of the renin-angiotensin system. In the present studies we found plasma arginine vasopressin (AVP) concentrations-3-fold higher than those in rats with benign renal hypertension, and 4- to 5-fold higher than those in normotensive control rats. Analysis of individual values showed considerable scatter; about 50% of the values fell in the range of benign hypertensive or control rats. When a specific AVP antiserum was injected, iv, into eight conscious unrestrained MH rats, BP transiently fell toward control values in four; in one, BP fell by only 10 mm Hg, and three other MH rats showed no response. In the same rats, injection of a specific angiotensin II antiserum always induced a transient fall in BP. On the basis of these and previously reported observations, we conclude that, subsequent to sodium and water loss and activation of the renin-angiotensin system, vasopressin release is stimulated in a significant number of MH rats and that, in these rats, vasopressin may cause significant systemic vasoconstriction. Thereby vasopressin may contribute to the development of malignant renal hypertension in rats.

Topics: Animals; Arginine Vasopressin; Blood Pressure; Hypertension, Malignant; Hypertension, Renal; Immune Sera; Male; Natriuresis; Rats; Renal Artery Obstruction; Sodium; Vasoconstriction; Vasopressins; Water-Electrolyte Balance

Acute renal artery stenosis in hydropenic dogs caused a contralateral increase in urine volume and free water clearance without change in glomerular filtration, renal blood flow, or osmolar clearance. The increase in urine volume was not dependent on the development of hypertension since it occurred in animals pretreated with trimethaphan but was dependent upon angiotensin since it was presented with angiotensin blockade with Saralasin. The effect was not caused by angiotensin inhibiting antidiuretic hormone release since the polyuria occurred in hypophysectomized animals receiving a constant infusion of 10 muU/kg per min of aqueous Pitressin. Since the rise in urine volume was associated with an increase in renal vein prostaglandin E concentration and was prevented by pretreatment with indomethacin (5 mg/kg) the results suggest that the rise in plasma angiotensin after renal artery stenosis causes an increase in contralateral prostaglandin E synthesis with resultant antagonism to antidiuretic hormone at the collecting tubule.

Topics: Animals; Blood Pressure; Dogs; Glomerular Filtration Rate; Indomethacin; Polyuria; Prostaglandins E; Renal Artery Obstruction; Renin; Saralasin; Sodium; Trimethaphan; Vasopressins

Topics: Aminohippuric Acids; Animals; Carbon Radioisotopes; Constriction; Female; Glomerular Filtration Rate; Hypertension, Renal; Inulin; Kidney; Kidney Concentrating Ability; Kidney Function Tests; Loop of Henle; Natriuresis; Osmolar Concentration; Potassium; Rats; Regional Blood Flow; Renal Artery Obstruction; Sodium; Urine; Vasopressins; Water

Topics: Animals; Blood Pressure; Depression, Chemical; Desoxycorticosterone; Diuresis; Dogs; Female; Glomerular Filtration Rate; Kidney; Kidney Function Tests; Osmolar Concentration; Prostaglandins; Regional Blood Flow; Renal Artery Obstruction; Renin; Stimulation, Chemical; Vasopressins; Water Deprivation; Water-Electrolyte Balance

Topics: Angiotensin II; Animals; Constriction; Dogs; Epinephrine; Magnesium Sulfate; Mesenteric Arteries; Norepinephrine; Phenylephrine; Potassium Chloride; Renal Artery; Renal Artery Obstruction; Vasoconstrictor Agents; Vasomotor System; Vasopressins

Topics: Adolescent; Adult; Aminohippuric Acids; Contrast Media; Creatinine; Diuresis; Humans; Hyperplasia; Hypertension, Renal; Kidney Function Tests; Methods; Middle Aged; Renal Artery Obstruction; Sodium; Sodium Chloride; Urea; Urinary Catheterization; Urography; Vasopressins

Topics: Adult; Aged; Cobalt Isotopes; Diuresis; Diuretics; Female; Glomerular Filtration Rate; Humans; Hypertension; Hypertension, Renal; Iodine Isotopes; Iodohippuric Acid; Kidney Function Tests; Male; Mannitol; Middle Aged; Pyelonephritis; Renal Artery Obstruction; Urea; Vasopressins; Vitamin B 12

Topics: Adolescent; Adult; Atrophy; Female; Humans; Kidney Function Tests; Male; Middle Aged; Potassium; Pyelonephritis; Renal Artery Obstruction; Sodium; Vasopressins

Topics: Angiotensin II; Blood Pressure; Diagnosis, Differential; Humans; Hypertension; Hypertension, Renal; Renal Artery Obstruction; Vasopressins

Topics: Absorption; Animals; Blood Chemical Analysis; Diuresis; Dogs; Extracellular Space; Glomerular Filtration Rate; Inulin; Isotonic Solutions; Kidney Tubules; Renal Artery Obstruction; Sodium; Sodium Chloride; Urine; Vasopressins

Topics: Animals; Biological Assay; Humans; Hypertension, Renal; Kidney Diseases; Kidney Function Tests; Plasma; Preoperative Care; Rats; Renal Artery Obstruction; Renal Veins; Vascular Surgical Procedures; Vasopressins

Topics: Animals; Constriction; Creatine; Creatinine; Diuresis; Dogs; Hypotension; Kidney Function Tests; Kidney Glomerulus; Osmosis; Pathology; Renal Artery Obstruction; Research; Shock, Hemorrhagic; Vasopressins

Topics: Blood Pressure Determination; Diagnosis; Diuresis; Glomerular Filtration Rate; Humans; Hypertension; Hypertension, Renal; Insulin; Kidney; Kidney Diseases; Kidney Function Tests; Natriuresis; Pharmacology; Renal Artery Obstruction; Urea; Vasopressins

Topics: Angiotensins; Aortic Diseases; Brain; Brain Damage, Chronic; Dehydration; Diabetes Insipidus; Diabetes Insipidus, Neurogenic; Hexamethonium Compounds; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Kidney Function Tests; Norepinephrine; Physiology; Renal Artery Obstruction; Vasopressins; Water-Electrolyte Balance

Topics: Bis-Trimethylammonium Compounds; Epinephrine; Hypertension; Hypertension, Renal; Pharmacology; Rabbits; Renal Artery Obstruction; Research; Vasomotor System; Vasopressins