HAEMODYNAMIC STUDIES IN MAN BEFORE AND AFTER HYPOPHYSECTOMY

1962 ◽  
Vol 39 (2) ◽  
pp. 308-322 ◽  
Author(s):  
Göran Bojs ◽  
Thomas Falkheden ◽  
Björn Sjögren ◽  
Edvardas Varnauskas

ABSTRACT Determinations of cardiac output and oxygen consumption simultaneously with measurements of glomerular filtration rate and renal plasma flow were performed before and after hypophysectomy in two cases of acromegaly, two cases of metastatic mammary carcinoma, one case of diabetes mellitus and in one case of chromophobe adenoma. After hypophysectomy evidence of adrenocortical insufficiency was present in all but one subject and these patients were on substitution therapy with cortisone (17,21-dihydroxy-pregn-4-ene 3,11,20-trione) at the time of the postoperative studies. In two patients at least, postoperative hypothyroidism could not be demonstrated. In all cases, however, hypophysectomy was followed by a marked and roughly parallel reduction in cardiac output and oxygen consumption. A substantial decrease in glomerular filtration rate, renal plasma flow and renal blood flow following hypophysectomy was also found while no or only slight changes in mean brachial arterial blood pressure were observed. The changes in renal function did not always parallel the reduction in cardiac output.

1991 ◽  
Vol 1 (12) ◽  
pp. 1271-1277
Author(s):  
A J King ◽  
J L Troy ◽  
S Anderson ◽  
J R Neuringer ◽  
M Gunning ◽  
...  

The role of nitric oxide in the modulation of systemic and renal hemodynamics was examined by using N omega-monomethyl-L-arginine (L-NMMA, 110 micrograms/kg/min), a competitive inhibitor of the conversion of L-arginine to nitric oxide. L-NMMA or saline vehicle (9.6 microL/min) was infused intravenously into anesthetized euvolemic Munich-Wistar rats. After 30 min, L-NMMA resulted in a uniform increase in mean arterial blood pressure (111 +/- 1 to 128 +/- 2 mmHg; P less than 0.05) and a modest reduction in renal plasma flow rate (4.4 +/- 0.2 to 4.2 +/- 0.1 mL/min; P less than 0.05), without change in glomerular filtration rate (1.16 +/- 0.03 to 1.15 +/- 0.03 mL/min); vehicle had no effect on these renal parameters. These rats were then subdivided to receive an intravenous infusion (37 microL/min) of either 10% glycine, 11.4% mixed amino acids, or equiosmolar dextrose. L-NMMA pretreatment markedly attenuated glycine-induced hyperfiltration (10 +/- 6 versus 33 +/- 5%, L-NMMA versus vehicle; P less than 0.05) and obliterated the renal hyperemic response (-7 +/- 6 versus 16 +/- 4%, L-NMMA versus vehicle; P less than 0.05). L-NMMA also caused modest blunting of the mixed amino acid-induced hyperfiltration (18 +/- 4 versus 30 +/- 4%, L-NMMA versus vehicle; P = 0.056) but failed to curtail the renal hyperemia (16 +/- 6 versus 20 +/- 4%). Dextrose had no effect on glomerular filtration rate or renal plasma flow.(ABSTRACT TRUNCATED AT 250 WORDS)


1961 ◽  
Vol 37 (4) ◽  
pp. 616-622 ◽  
Author(s):  
Göran Bojs ◽  
Thomas Falkheden ◽  
Björn Sjögren

ABSTRACT Clearances of inulin and para-aminohippuric acid as well as renal extraction of para-aminohippuric acid were studied in six hypophysectomized patients, in one case of craniopharyngioma and in two cases of chromophobe adenoma. All subjects showed evidence of adrenocortical insufficiency and received substitution therapy with cortisone (17,21-dihydroxy-pregn-4-ene-3,11,20-trione) at the time of this investigation. Thyroid insufficiency was demonstrated in only four cases. Glomerular filtration rate and renal plasma flow were decreased to a varying extent, the reduction being most marked in the hypothyroid subjects. Irrespective of the degree of reduction in glomerular filtration rate and renal plasma flow a normal renal extraction of para-aminohippuric acid was found.


1958 ◽  
Vol 193 (3) ◽  
pp. 639-643 ◽  
Author(s):  
William P. Blackmore

The effects of constant intravenous infusion of serotonin with doses of 5 and 10 µg/kg/min. on glomerular filtration rate, effective renal plasma flow, urine flow and sodium excretion were studied in trained, unanesthetized female dogs. A small but significant decrease in glomerular filtration rate associated with increased renal plasma flow occurred at the 5 µg/kg/min. dose indicating a specific effect of serotonin on the kidney. Similar changes were noted with the 10 µg/kg/min. dose plus a marked antidiuretic effect that occurred in the absence of any significant change in mean arterial blood pressure and an intact neurohypophysis indicating a direct action on water reabsorption in the kidney. Urinary sodium excretion decreased with both doses as a result of a decline in glomerular filtration rate associated with increased tubular reabsorption. These results indicate that serotonin has a specific effect on the kidney and suggest that this substance may alter the caliber of the glomerular vessels to decrease renal vascular resistance.


1976 ◽  
Vol 50 (3) ◽  
pp. 165-169 ◽  
Author(s):  
M. O. Farber ◽  
J. J. Szwed ◽  
A. R. Dowell ◽  
R. A. Strawbridge

1. Effective renal plasma flow, glomerular filtration rate and cardiac output were measured in osmotically loaded dogs before and during comparable acute respiratory and metabolic acidosis. 2. Urine output increased in control dogs and in animals with metabolic acidosis, but declined with respiratory acidosis. Effective renal plasma flow and glomerular filtration rate declined with respiratory and metabolic acidosis. 3. When respiratory acidosis was buffered with sodium bicarbonate, urine volume increased and glomerular filtration rate and effective renal plasma flow were unchanged; with trihydroxymethylaminomethane, urine volume increased but glomerular filtration rate and effective renal plasma flow fell. 4. When metabolic acidosis was buffered with sodium bicarbonate, urine volume increased; with trihydroxymethylaminomethane, urine volume increased but glomerular filtration rate fell. Cardiac output declined only during metabolic acidosis, both buffered and unbuffered. 5. These studies demonstrate that, even with osmotic loading: (1) respiratory acidosis causes a decrease in glomerular filtration rate, effective renal plasma flow and urine volume; (2) metabolic acidosis depresses glomerular filtration rate and effective renal plasma flow but does not change urine volume even though cardiac output falls; (3) sodium bicarbonate is more effective than trihydroxymethylaminomethane in preserving renal function during respiratory and metabolic acidosis.


1995 ◽  
Vol 268 (4) ◽  
pp. R978-R988 ◽  
Author(s):  
S. T. Turner ◽  
S. L. Reilly

Renal plasma flow, glomerular filtration rate, and cardiac output are traditionally indexed for body surface area by expressing these traits as per-surface-area ratios. Indexing is intended to remove interindividual variation attributable to differences in body size. Regression is an alternative method commonly used to adjust other biological traits for the effects of a covariate, such as body surface area. The purpose of this study was to compare the indexing and regression methods of adjusting renal plasma flow, glomerular filtration rate, and cardiac output for interindividual differences in body surface area. We estimated renal plasma flow by the clearance of p-aminohippurate, glomerular filtration rate by clearance of inulin, and cardiac output by thoracic electrical impedance in a sample of 78 unrelated females and 78 unrelated males (ages 20-49.9 yr) from the general population of Rochester, MN. The indexing method created negative dependencies of renal plasma flow and cardiac output on body surface area and failed to eliminate the positive dependency of glomerular filtration rate on body surface area. Moreover, indexing obscured differences in mean renal plasma flow between females and males and created differences in mean cardiac output between the genders. In contrast, the regression method consistently eliminated dependencies of each trait on body surface area and did not lead to inappropriate inferences about mean differences in these traits between females and males. We conclude that the indexing method of adjusting renal plasma flow, glomerular filtration rate, and cardiac output for interindividual differences in body surface area should be abandoned and replaced by use of the regression method.


1971 ◽  
Vol 10 (01) ◽  
pp. 16-24
Author(s):  
J. Fog Pedersen ◽  
M. Fog Pedersen ◽  
Paul Madsen

SummaryAn accurate catheter-free technique for clinical determination simultaneouslyof glomerular filtration rate and effective renal plasma flow by means of radioisotopes has been developed. The renal function is estimated by the amount of radioisotopes necessary to maintain a constant concentration in the patient’s blood. The infusion pumps are steered by a feedback system, the pumps being automatically turned on when the radiation measured over the patient’s head falls below a certain preset level and turned off when this level is again readied. 131I-iodopyracet was used for the estimation of effective renal plasma flow and125I-iothalamate estimation of the glomerular filtration rate. These clearances were compared to the conventional bladder clearances and good correlation was found between these two clearance methods (correlation coefficients 0.97 and.90 respectively). The advantages and disadvantages of this new clearance technique are discussed.


1965 ◽  
Vol 48 (3) ◽  
pp. 348-354 ◽  
Author(s):  
Thomas Falkheden ◽  
Ingmar Wickbom

ABSTRACT Measurements of glomerular filtration rate (GFR) and renal plasma flow (RPF) were performed in close connection with roentgenographic estimation of kidney size, before and after hypophysectomy, in 10 patients (four cases of metastatic mammary carcinoma, five cases of diabetic retinopathy and one case of acromegaly). Hypophysectomy was regularly followed by a decrease in GFR and RPF. In most cases, a reduction in the roentgenographic kidney size was also observed. However, the changes in the roentgenographic kidney size and calculated kidney weight after hypophysectomy were smaller and occurred at a slower rate than the alterations in GFR and RPF. The results favour the view that, primarily, the decrease in GFR and RPF following hypophysectomy is essentially functional rather than due to a reduced kidney mass.


Sign in / Sign up

Export Citation Format

Share Document