scholarly journals THE PATHOGENESIS OF HYPERTENSION INDUCED BY RENAL CONSTRICTION

1950 ◽  
Vol 92 (1) ◽  
pp. 59-76 ◽  
Author(s):  
L. J. Rather
Keyword(s):  
Blood Pressure ◽  
Young Male ◽  
The Other ◽  
Unilateral Nephrectomy ◽  
Albino Rats ◽  
Renal Hypertrophy ◽  
Ether Anesthesia ◽  
Frequency Distributions ◽  
Contralateral Kidney ◽  
Blood Pressures

Blood pressures were determined on forty-two young male albino rats and a basal level established. The rats were then divided into four groups and subjected to one of the following operations: (a) unilateral nephrectomy with exposure and handling of the opposite kidney; (b) unilateral nephrectomy and constriction of the remaining kidney with a silk figure-of-eight ligature; (c) unilateral renal constriction with a silk figure-of-eight ligature, the other kidney being left intact after exposure and handling; (d) unilateral nephrectomy and removal of the poles of the contralateral kidney (three-quarters nephrectomy). The animals were followed for 50 days, during which blood pressures were measured on twenty occasions, then killed by exsanguination under ether anesthesia. The organs were weighed according to a standardized procedure and studied histologically. Individual determinations of serum creatinine and of the hematocrit levels were made. Mean lines and frequency distributions of blood pressure were subjected to statistical analysis. A definitely significant increase in blood pressure developed in the group subjected to operation (b) within 4 days postoperative. In none of the other groups did hypertension develop. Analysis of the individual renal weights and creatinine levels indicates the independence of the development of hypertension from the total mass of functioning renal tissue. Nor is it dependent on the prevention of renal hypertrophy or the presence of fibrous perinephritis. The effect is probably due to the production of a disturbance of hemodynamics or tissue tension with the liberation of a pressor substance by the injured kidney.

scholarly journals STUDIES ON RENAL JUXTAGLOMERULAR CELLS

1957 ◽  
Vol 105 (6) ◽  
pp. 501-508 ◽  
Author(s):  
Phyllis M. Hartroft
Keyword(s):  
Blood Pressure ◽  
Renal Artery ◽  
Blood Supply ◽  
Compensatory Hypertrophy ◽  
The Other ◽  
Unilateral Nephrectomy ◽  
Juxtaglomerular Cells ◽  
Contralateral Kidney ◽  
Juxtaglomerular Cell ◽  
Hydronephrotic Kidney

Hypertension in rats produced by constriction of one renal artery was associated with degranulation of juxtaglomerular cells in the contralateral, undamped, kidney. These findings are consistent with those of other investigators. Furthermore, the degree of granulation (JGI) in the unclamped kidney was inversely correlated with the level of blood pressure (r = –0.7). Degranulation of JG cells also occurred in rats made hypertensive by application of a "figure-of-eight" ligature to one kidney and removal of the other one, except when the interference in blood supply was so severe that scarring resulted. In these damaged areas, granules persisted or increased in number even though they were decreased in adjacent relatively normal areas. Occlusion of one ureter in rats produced severe hydronephrosis in the homolateral kidney and an elevation in blood pressure. Juxtaglomerular cell granules persisted in the hydronephrotic kidney but were decreased in the contralateral one. This finding confirmed the results of the above experiments. Unilateral nephrectomy in comparable rats had no effect on the degree of granulation of JG cells in the remaining kidney or on the level of blood pressure under the conditions of these experiments. The possibility that degranulation of JG cells in the contralateral kidney in the rats described above was due to compensatory hypertrophy was thereby excluded. An elevation in blood pressure was therefore implicated as an important factor in causing degranulation of juxtaglomerular cells.

Role of Autonomic Nervous System in Maintenance of Cerebral and Renal Hypertension

1957 ◽  
Vol 188 (2) ◽  
pp. 371-374 ◽  
Author(s):  
Sol Rothman ◽  
Douglas R. Drury
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Renal Hypertension ◽  
The Other ◽  
Peripheral Vasculature ◽  
Blood Pressures ◽  
Sympathetic Nervous ◽  
Blood Pressure Responses

The blood pressure responses to various drugs were investigated in renal hypertensive, cerebral hypertensive and normotensive rabbits. Hexamethonium bromide and Dibenamine reduced the blood pressures of renal and cerebral hypertensives. Effects in the normal were insignificant. The cerebral hypertensive's blood pressure was slightly affected by benzodioxane. Blood pressure was not reduced at all in the other groups. Blood pressure of the renal hypertensive rabbit was greatly reduced by Veriloid and dihydroergocornine. Blood pressures of cerebral and normal animals were affected to a lesser degree. The results suggest that maintenance of hypertension in the cerebral hypertensive rabbit depends on an overactive sympathetic nervous system, possibly due to the release of medullary pressor centers from inhibitory impulses originating in higher centers; whereas, the maintenance of hypertension in the renal hypertensive rabbit may be attributed to an increased reactivity of the peripheral vasculature to a normal sympathetic tone.

scholarly journals EFFECTS OF CHRONIC EXCESS SALT INGESTION

1967 ◽  
Vol 126 (4) ◽  
pp. 687-699 ◽  
Author(s):  
Lewis K. Dahl ◽  
Knud D. Knudsen ◽  
Martha Heine ◽  
George Leitl
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Response ◽  
Pressure Response ◽  
Sensitive Strain ◽  
The Other ◽  
Experimental Hypertension ◽  
Highly Sensitive ◽  
Blood Pressures ◽  
Genetically Determined ◽  
Resistant Animal

Parabiosis has been found to modify the expected blood pressure response of rats from two strains with opposite genetic propensities for experimental hypertension. When a member from one strain was united in parabiosis with a member from the other and both were maintained on high NaCl diet, the rat from the strain ordinarily resistant to it rapidly developed hypertension, in contrast to appropriate controls from this strain. The development of hypertension in this resistant animal preceded that in its mate from the strain highly sensitive to hypertension. In the latter, both the level of hypertension and mortality were significantly less than in its control. It seems likely that the hypertension observed is the resistant parabiont was initiated in its partner from the sensitive strain. This modification in blood pressures was not observed in the absence of a high NaCl diet. Parabiosis between animals from the same strain did not alter their response. Thus, as in earlier experiences (1–4) the interaction of a nongenetic factor (NaCl) with the appropriate genetic substrate appeared to be necessary for the development of hypertension. The findings are interpreted as evidence that a transmittable humoral influence plays an important role in the pathogenesis of rat hypertension. The presence of this agent is genetically determined but, under the conditions of these experiments, it took the added stimulus of dietary NaCl to demonstrate its existence.

scholarly journals THE DEGREE OF COMPENSATORY RENAL HYPERTROPHY FOLLOWING UNILATERAL NEPHRECTOMY

1938 ◽  
Vol 67 (4) ◽  
pp. 515-519 ◽  
Author(s):  
Lois L. MacKay ◽  
T. Addis ◽  
Eaton M. MacKay
Keyword(s):  
Protein Intake ◽  
Compensatory Hypertrophy ◽  
Unilateral Nephrectomy ◽  
Albino Rats ◽  
Renal Hypertrophy ◽  
Young Rats ◽  
Compensatory Renal Hypertrophy ◽  
Old Rats

Compensatory hypertrophy of the kidney in albino rats is increased by an increase in the protein intake. The effect is greater in old rats than young rats. Successive increases in the protein intake are followed by a reduction in the increase in the degree of compensatory renal hypertrophy.

scholarly journals THE INFLUENCE OF ANEMIA ON PHAGOCYTIC FUNCTIONS IN RATS

Blood ◽  
1947 ◽  
Vol 2 (Special_Issue_Number_1) ◽  
pp. 108-116 ◽  
Author(s):  
L. JOE BERRY ◽  
EVELYN C. HALLER
Keyword(s):  
Phagocytic Activity ◽  
Young Male ◽  
Mineral Oil ◽  
Control Group ◽  
Albino Rats ◽  
Total Blood ◽  
Ether Anesthesia ◽  
Experimental Animals ◽  
Cell Counts

Abstract 1. Young male albino rats were subjected to weekly bleedings by cardiac puncture for eleven weeks. Phagocytic activity of the granulocytes in this blood was determined at each bleeding by a whole blood in vitro technic and compared to that of the blood from a control group consisting of 5 animals. Total blood cell counts and hemoglobin determinations were also made each week with both groups. The control animals were not bled more frequently than once in six weeks. 2. Phagocytic function in the bled animals increased approximately 40 per cent above the values for the controls during the period of weekly bleeding. There was no evidence of anemia developing during this period. 3. The experimental animals were then bled three times weekly for five weeks. Phagocytosis increased about 80 per cent above control values and the anemia became severe. Macrophages obtained from a peritoneal exudate stimulated by injections of mineral oil at the end of this five week period became approximately twice as phagocytic as macrophages from control animals. 4. With the cessation of bleeding, there was a complete remission of the anemia as measured after two weeks and the phagocytic activity of the blood had dropped below normal. There was a partial return to normal within four weeks, but it was still slightly subnormal at six weeks. The macrophages, on the other hand, were normal when tested four weeks after recovery. 5. Control animals subjected to ether anesthesia thrice weekly for six weeks showed normal phagoctyic functions, as measured with blood and macrophages. 6. These results are discussed in the light of earlier experiments on the phagocytic activity of blood from anemic humans.

scholarly journals Concentration of phosphoribosyl pyrophosphate in renal hypertrophy. Contrasting effects of early diabetes and unilateral nephrectomy

1986 ◽  
Vol 239 (1) ◽  
pp. 241-244 ◽  
Author(s):  
S Kunjara ◽  
M Sochor ◽  
A L Greenbaum ◽  
P McLean
Keyword(s):  
Nucleic Acid ◽  
Unilateral Nephrectomy ◽  
Phosphoribosyl Pyrophosphate ◽  
Renal Hypertrophy ◽  
Early Diabetes ◽  
Nucleotide Synthesis ◽  
Contralateral Kidney ◽  
Increment Of Growth ◽  
Renal Enlargement

Studies were made of the renal phosphoribosyl pyrophosphate (PPRibP) content and PPRibP synthetase (EC 2.7.6.1) activity in rats diabetic for 5, 14 or 20 days, or unilaterally nephrectomized (UN) for 5 days, and in doubly lesioned animals. Approximately equal degrees of renal enlargement were found after 5 days diabetes or 5 days UN. In the doubly lesioned animals the increment of growth was additive. Unilateral nephrectomy of 5 days duration, in contrast with diabetes, had no effect on the PPRibP content of the contralateral kidney, nor did it modify the renal PPRibP content when performed on animals diabetic for 5, 14 or 20 days. The activity of PPRibP synthetase was unaffected by diabetes, UN or diabetes +UN. The results pinpoint a stage of nucleotide synthesis which is differentially affected by the two stimuli, in line with evidence for differences in regulation of nucleic acid turnover in the two conditions.

scholarly journals The Influence of Maturity Status on Resting Energy Expenditure, Body Composition and Blood Pressure in Physically Active Children

Healthcare ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 216
Author(s):  
Edyta Łuszczki ◽  
Maciej Kuchciak ◽  
Katarzyna Dereń ◽  
Anna Bartosiewicz
Keyword(s):  
Blood Pressure ◽  
Body Composition ◽  
Energy Expenditure ◽  
Young Male ◽  
Resting Energy Expenditure ◽  
Fat Free Mass ◽  
The Other ◽  
Height Velocity ◽  
Peak Height Velocity ◽  
Resting Energy

Peak height velocity (PHV) is the period where the maximum rate of growth occurs. The moment the sports player reaches PHV can be estimated by monitoring the growth of body structures. The aim of this study was to assess changes in resting energy expenditure (REE), body composition and blood pressure in young, male soccer players between the pre-PHV, circa-PHV and post-PHV periods. This transverse study was conducted among 184 children aged 9 to 17 and included measurements of the resting energy expenditure (REE) using indirect calorimetry, body composition (bioimpedance) and blood pressure (sphygmomanometer). In addition, births in each quartile were analyzed. Children in the pre-PHV group had significantly lower REE values compared to the other two groups (p < 0.0001). The differences in the value of the REE between the children in the circum and post groups were not statistically significant. Additionally, the fat-free mass was significantly lower in the pre-PHV period compared to the other two periods (p < 0.0001), and the same relationship concerned the z-score body mass index (BMI) and systolic blood pressure. Early-born players were overrepresented (p < 0.05).

Intraventricular blood pressures in the chicken

1960 ◽  
Vol 198 (1) ◽  
pp. 153-154 ◽  
Author(s):  
H. E. Bredeck
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systolic Pressure ◽  
Left Ventricular Pressure ◽  
Left Ventricular ◽  
The Other ◽  
Blood Pressures ◽  
Left And Right ◽  
The Right ◽  
Made In

Direct heart punctures were made in two groups of unanesthetized chickens to determine the left and right intraventricular blood pressures. One group was composed of nonlaying birds 28–30 weeks old and the other of laying hens 65–67 weeks of age. Heart rates and the respiratory influence on pressure were also measured. Average pressures obtained were 144/0 and 21/ - 1 mm Hg for the left and right ventricle, respectively. Respiratory efforts caused a mean fluctuation in systolic pressure of approximately 8 mm Hg in the left ventricle and 4 mm Hg in the right. With the exception of the right ventricular diastolic blood pressure, there were no significant pressure or pulse rate differences between the two groups. The heart rate and left ventricular pressure were found to be significantly correlated ( P < .01) in both groups of birds.

Source of kidney determines blood pressure in young renal transplanted rats

1993 ◽  
Vol 265 (1) ◽  
pp. F104-F111 ◽  
Author(s):  
D. Kopf ◽  
R. Waldherr ◽  
R. Rettig
Keyword(s):  
Blood Pressure ◽  
Spontaneously Hypertensive Rat ◽  
Young Male ◽  
Normal Weight ◽  
F1 Hybrids ◽  
Bilateral Nephrectomy ◽  
Age Related ◽  
Blood Pressures ◽  
Wistar Kyoto ◽  
Related Increase

Recipients of a renal graft from adult stroke-prone spontaneously hypertensive rat (SHRSP) but not normotensive Wistar-Kyoto rat (WKY) donors have been shown to develop posttransplantation hypertension. To investigate whether hypertension would also travel with the kidneys from young prehypertensive SHRSP and whether the age-related increase in blood pressure in F1 hybrids (F1H) bred from SHRSP and WKY parents was attenuated by early bilateral nephrectomy and transplantation of a WKY kidney, we transplanted kidneys from 14 male SHRSP and 16 WKY donors aged 35-42 days to young male F1H. Recipients had both native kidneys removed. Fifteen unilaterally nephrectomized nontransplanted F1H served as controls. At the time when kidneys were harvested for transplantation, systolic blood pressures in young SHRSP and WKY donors were not significantly different (114 +/- 5 vs. 113 +/- 3 mmHg). After transplantation, recipients of an SHRSP kidney rapidly developed posttransplantation hypertension with systolic blood pressures above 180 mmHg at 3 mo after transplantation. In contrast, systolic blood pressure in recipients of a WKY kidney rose only slightly with increasing age and remained significantly lower than in non-transplanted controls. Transplanted rats exhibited normal weight gain, and renal function (glomerular filtration rate, renal blood flow) in grafted kidneys was well preserved; plasma renin activity was reduced compared with nontransplanted controls. These data demonstrate that 1) hypertension can be transmitted to normotensive recipients by transplantation of a kidney from young prehypertensive SHRSP donors and 2) the age-related increase in arterial pressure in F1H is attenuated by early bilateral nephrectomy and transplantation of a WKY kidney.(ABSTRACT TRUNCATED AT 250 WORDS)

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