Increased Erythrocyte Sodium-Lithium Countertransport Activity in essential Hypertension is Due to an Increased Affinity for Extracellular Sodium

1990 ◽  
Vol 79 (4) ◽  
pp. 365-369 ◽  
Author(s):  
P. A. Rutherford ◽  
T. H. Thomas ◽  
R. Wilkinson

1. Sodium-lithium countertransport activity in a standard assay, its sodium affinity constant and maximum velocity were measured in erythrocytes from normal subjects and from essential hypertensive patients with and without a family history of hypertension. 2. In normal subjects the sodium concentration used in the standard assay was similar to the sodium affinity constant so that the activity measured in this assay was less than the maximum velocity. 3. In patients with essential hypertension and a positive family history, 33% had a sodium-lithium countertransport activity greater than the upper limit of the normal control range (0.4 mmol of Li+ h−1 l−1 of cells). 4. The reason for the raised sodium-lithium countertransport activity was an increased sodium affinity (lower sodium affinity constant) at the outside ion-binding site. 5. Of the patients with essential hypertension and a positive family history but sodium-lithium countertransport activity within the normal range in the standard assay, 30% also had a low sodium affinity constant. 6. A low sodium affinity constant at the outside site of the sodium-lithium countertransporter may be a more specific indicator for a group of patients with inherited hypertension than the standard sodium-lithium countertransport activity assay.

1990 ◽  
Vol 258 (6) ◽  
pp. C988-C994 ◽  
Author(s):  
J. Takaya ◽  
N. Lasker ◽  
R. Bamforth ◽  
M. Gutkin ◽  
L. H. Byrd ◽  
...  

To explore the etiology of altered Ca metabolism in essential hypertension, we studied parameters, i.e., maximal initial reaction velocity (Vmax) and Michaelis constant (Km), of Ca activation kinetics of Ca2(+)-ATPase in membrane fractions (isolated by a sucrose gradient) from platelets of blacks and whites, 27 of whom were essential hypertensives, 17 of whom were normotensives with a family history of essential hypertension, and 10 of whom were normotensives without a family history of the disease. The Vmax of hypertensives was significantly lower than in normotensives without a family history of essential hypertension (hypertensives, 14.99 +/- 1.71 nmol Pi.mg protein-1.min-1; normotensives, positive family history, 22.67 +/- 3.17 nmol Pi.mg protein-1.min-1; normotensives, negative family history, 27.54 +/- 4.37 nmol Pi.mg protein-1.min-1; overall, P = 0.0078). The Km was lower in both hypertensives and normotensives with a positive family history of essential hypertension as compared with normotensives with a negative family history of the disease (hypertensives, 1.70 +/- 0.23 microM; normotensives, positive family history, 1.38 +/- 0.2 microM; normotensives, negative family history, 2.79 +/- 0.58 microM; overall, P = 0.0251). Furthermore, the Km in whites was inversely related to plasma renin activity (r = 0.50; P less than 0.005). We propose that a lower Vmax for Ca2(+)-ATPase may play a role in the higher level of free Ca in platelets of essential hypertensives and that a higher affinity of the enzyme to Ca may reflect a process compensating for the lower Vmax. We also suggest that a higher Km for Ca2(+)-ATPase in juxtaglomerular cells of whites would result in blunting the release of renin.


1992 ◽  
Vol 3 (4) ◽  
pp. S34
Author(s):  
T P Hannedouche ◽  
L P Marques ◽  
P Guicheney ◽  
B Lacour ◽  
C Boitard ◽  
...  

The offspring of essential hypertensive parents have been found to exhibit abnormalities in renal hemodynamics and sodium handling before the eventual occurrence of hypertension. The reported abnormalities represent a wide spectrum of changes including increased GFR, normal or decreased RPF, slight increase in blood pressure (although within the normal range), and an exaggerated natriuresis response to a sodium load. The heterogeneity of these abnormalities may reflect the specific conditions of the studies, the lability of the changes, or different subgroups of subjects with genetic predisposition to essential hypertension. Several lines of evidence have suggested a relationship between hypertension and the development of diabetic nephropathy in insulin-dependent diabetics. This laboratory has found that recent-onset insulin-dependent diabetics can exhibit renal hemodynamics abnormalities very early in the course of diabetes according to a positive or negative family history of essential hypertension. These changes include increased GFR and mean arterial pressure, but no differences in renal sodium and lithium handling in diabetics with a genetic predisposition to essential hypertension. In addition, diabetics with a positive family history of essential hypertension exhibited a more-marked vasodilative response to an acute interruption of the renin-angiotensin system, further suggesting inadequate angiotensin modulation of renal vascular tone. The significance of these abnormalities in relation to the development of diabetic nephropathy requires further investigation.


1982 ◽  
Vol 63 (s8) ◽  
pp. 371s-374s ◽  
Author(s):  
L. Andrén ◽  
S. Piros ◽  
L. Hansson ◽  
H. Herlitz ◽  
O. Jonsson

1. Stimulation with noise (100 dBA) for 10 min caused a significant increase in diastolic and mean arterial pressure in normotensive subjects with and without a positive family history of hypertension. 2. The blood pressure response in the group with a positive family history of hypertension was due to a significant increase in total peripheral resistance (9%, P < 0.05); no such change was seen in the group without heredity for hypertension. 3. Systolic blood pressure, heart rate, stroke volume and cardiac output did not change significantly during exposure to noise. 4. There was no difference between the groups in mean intracellular sodium concentration measured in erythrocytes.


1993 ◽  
Vol 84 (2) ◽  
pp. 225-230 ◽  
Author(s):  
Claudia Ferrier ◽  
Helen Cox ◽  
Murray Esler

1. In prehypertension, abnormalities in cardiovascular control mechanisms have been described. It has been postulated that this may involve hereditary disturbances in the sympathetic regulation of blood pressure. Since the neurochemical methods used to test sympathetic nervous system activity have been rather imprecise, in the present study we have applied noradrenaline plasma kinetic methodology to evaluate sympathetic activity in normotensive subjects with a familial predisposition to essential hypertension. 2. Total body noradrenaline spillover to plasma, an index of integrated sympathetic nerve firing rates, was calculated during infusion of l-[7-3H] noradrenaline in 11 normotensive offspring of essential hypertensive parents and 11 age-, height- and weight-matched normotensive offspring of normotensive parents. 3. The resting arterial plasma noradrenaline concentration was higher in healthy subjects with a family history of essential hypertension (1.41 ± 0.15 nmol/l, mean ± SEM, P < 0.002) than in normotensive subjects with no family history of essential hypertension (0.82 ± 0.07 nmol/l). The overall rate of spillover of noradrenaline to plasma was also elevated in the normotensive offspring of hypertensive parents (4.34 ± 0.54 nmol/min) compared with subjects with a negative family history of essential hypertension (2.02 ± 0.20 nmol/min). Similarly, the arterial plasma concentration of the noradrenaline precursor 3,4-dihydroxyphenylalanine was higher in subjects with a positive family history of essential hypertension (7.55 ± 0.24 nmol/l) than in normotensive control subjects (5.97 ± 0.30 nmol/l, P < 0.001). Despite this apparent evidence of relative sympathetic nervous activation in the subjects with a positive family history of hypertension, their blood pressure and heart rate were only marginally, and non-significantly, higher. 4. Biochemical indices of sympathetic function in normotensive offspring of hypertensive parents suggest a familial disturbance in sympathetic nervous system activity, which may be a predictor for the development of hypertension in adult life.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Meng Wang ◽  
Wei-Wei Gong ◽  
Feng Lu ◽  
Ru-Ying Hu ◽  
Qing-Fang He ◽  
...  

Abstract Background Previous studies have indicated inconsistent relationships of diabetes with thyroid cancer risk, yet little is known in China. In this study, we aimed to investigate the associations between diabetes, diabetes duration and the risk of thyroid cancer in Chinese population. Methods A 1:1 matched case-control study was performed between 2015 and 2017 in Zhejiang Province including 2,937 thyroid cancer cases and 2,937 healthy controls. Odds ratios (ORs) with 95 % confidence intervals (CIs) for thyroid cancer were estimated in logistic regression models. Specific effects stratified by age, as well as sex, body mass index (BMI) and family history of diabetes were also examined. Results Overall, neither diabetes (OR = 0.75, 95 % CI: 0.21–2.73) nor diabetes duration (OR = 0.14, 95 % CI: 0.02–1.22 for diabetes duration ≦ 5 years; OR = 2.10, 95 % CI: 0.32–13.94 for diabetes duration > 5 years) was significantly associated with thyroid cancer. In stratified analyses, significant lower risk of thyroid cancer was observed among subjects with diabetes and shorter diabetes duration ( ≦ 5 years), but limited to those who were aged more than 40 years, female, overweight/obese and had positive family history of diabetes. Conclusions Diabetes and shorter diabetes duration were significantly associated with decreased risk of thyroid cancer in individuals characterized by older age, female sex, higher BMI and positive family history of diabetes.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Uzair Abbas ◽  
Bushra Imdad ◽  
Sikander Adil Mughal ◽  
Israr Ahmed Baloch ◽  
Afshan Mehboob Khan ◽  
...  

Abstract Objective MicroRNAs are known to regulate 60% of genes at post translational level. MicroRNAs including Micro RNA-29 family play a vital role in cellular activities and have validate role in numerous metabolic disorders inclusive of diabetes mellitus and its complications. While micro RNA profile changes years before the occurrence of disease. This cross-sectional study was conducted in non-diabetic adults of diabetic and non-diabetic parents to explore the early changes in expression of micro RNA-29 family as it can be served as early biomarker of type 2 diabetes in non-diabetic adults. This study was conducted from January 2019 to January 2021. Micro RNA was extracted from plasma of 50 participants and expression was compared through qPCR. While data was analyzed through SPSS version 21.0. Results 29a and 29b had lower expression in participants with family history of DM compared to those having no family history of DM (P < 0.0001). While micro RNA 29c was found to be significantly higher in participants with positive family history of type 2 diabetes as compared to those without family history of diabetes (P = 0.001).


1998 ◽  
Vol 43 (4) ◽  
pp. 375-380 ◽  
Author(s):  
Mary Jane Esplen ◽  
Brenda Toner ◽  
Jonathan Hunter ◽  
Gordon Glendon ◽  
Kate Butler ◽  
...  

Objective: To describe and illustrate elements of a group counselling approach designed to enhance the communication of risk information on breast cancer (BC) to women with a family history of this disease. Breast cancer is a leading cause of female cancer death. The most important risk factor for BC is a positive family history in at least 1 first-degree relative, and approximately one-third of women with BC have a family history of the disease. Recent evidence suggests that there is a significant psychological impact associated with having a family history of BC, and this may influence the psychological adjustment and response to being counselled for personal risk. New counselling approaches are required. Method: This paper describes a group therapy approach that incorporates principles of supportive-expressive therapy designed to address the emotional impact of being at risk for BC and to promote accuracy of perceived risk. The key elements of the intervention are described along with clinical illustrations from groups that are part of an ongoing study to develop and standardize the group therapy. Conclusion: Qualitative data from the groups suggest that this model of therapy is both feasible and effective.


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