Increased Sodium Content and Altered Sodium Transport in Thymocytes of Spontaneously Hypertensive Rats

1981 ◽  
Vol 61 (3) ◽  
pp. 313-316 ◽  
Author(s):  
R. B. Jones ◽  
J. Patrick ◽  
P. J. Hilton
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Rate Constant ◽  
Spontaneously Hypertensive Rats ◽  
Sodium Content ◽  
Strong Positive Correlation ◽  
Hypertensive Rats ◽  
Sodium Efflux ◽  
Spontaneously Hypertensive

1. The intracellular sodium content and the sodium efflux rate constant have been determined in vitro in thymocytes derived from the Okamato-Aoki strain of spontaneously hypertensive rats. 2. A strong positive correlation between the systolic blood pressure and the sodium content of thymocytes was observed (r = 0.59, n = 39, P < 0.001). 3. The rate constant for total sodium efflux was negatively correlated with systolic blood pressure (r = −0.43, n = 45, P < 0.005) and this was due to a fall in the ouabain-sensitive component of sodium efflux. 4. Sodium efflux, influx and the thymocyte potassium content were not related to the blood pressure.

Metformin decreases plasma insulin levels and systolic blood pressure in spontaneously hypertensive rats

1994 ◽  
Vol 267 (4) ◽  
pp. H1250-H1253 ◽  
Author(s):  
S. Verma ◽  
S. Bhanot ◽  
J. H. McNeill
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Plasma Insulin ◽  
Metformin Treatment ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Insulin Levels ◽  
Plasma Insulin Levels ◽  
Wistar Kyoto

To determine the relationship between hyperinsulinemia and hypertension in spontaneously hypertensive rats (SHR), the antihyperglycemic agent metformin was administered to SHR and their Wistar-Kyoto (WKY) controls, and its effects on plasma insulin levels and blood pressure were examined. Five-week-old rats were started on oral metformin treatment (350 mg.kg-1.day-1, which was gradually increased to 500 mg.kg-1.day-1 over a 2-wk period). Metformin treatment caused sustained decreases in plasma insulin levels in the SHR (27.1 +/- 2.3 vs. untreated SHR 53.5 +/- 2.7 microU/ml, P < 0.001) without having any effect in the WKY (30.7 +/- 2.2 vs. untreated WKY 37.8 +/- 1.6 microU/ml, P > 0.05). The treatment did not affect the plasma glucose levels in any group. Metformin treatment also attenuated the increase in systolic blood pressure in the SHR (157 +/- 6.0 vs. untreated SHR 196 +/- 9.0 mmHg, P < 0.001) but had no effect in the WKY (134 +/- 3 vs. untreated WKY 136 +/- 4 mmHg, P > 0.05). Furthermore, raising plasma insulin levels in the metformin-treated SHR to levels that existed in the untreated SHR reversed the effect of metformin on blood pressure (189 +/- 3 vs. untreated SHR 208 +/- 5.0 mmHg, P > 0.05). These findings suggest that either hyperinsulinemia may contribute toward the increase in blood pressure in the SHR or that the underlying mechanism is closely associated with the expression of both these disorders.

An antihypertensive extract of erythrocytes: effects on 45Ca uptake and efflux

1986 ◽  
Vol 64 (4) ◽  
pp. 424-429
Author(s):  
G. L. Wright ◽  
G. O. Rankin ◽  
W. D. McCumbee
Keyword(s):  
Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Calcium Uptake ◽  
Slow Component ◽  
Present Report ◽  
Calcium Stores ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Washout Curves

The present report describes some aspects of the effects of a recently described antihypertensive extract of erythrocytes (AHF) on calcium uptake and efflux in rat aortae. AHF was found to be present in the erythrocytes of both spontaneously hypertensive rats and normotensive rats. Furthermore, AHF obtained from erythrocytes of SH rats was shown to be equally effective in suppressing lanthanum-resistant calcium uptake in aortae from hypertensive and normotensive rats. AHF treatment prior to incubation of aortae with 45Ca caused an apparent increase in the total 45Ca uptake. The analysis of calcium washout curves obtained for tissue in calcium-free or lanthanum-containing media indicated that AHF had no significant effect on the rate of calcium loss from the slow component of efflux, though this compartment tended to be reduced in size. This indicated that the increase in the 45Ca content of AHF-exposed aortae prior to rinsing was confined to the rapid component of efflux. The loss of calcium from the rapidly exchanging compartment was enhanced in either of the efflux media used. The results suggest that a principal action of AHF involves an increase in the lability and exchangeability of calcium stores. In addition to its effects in resting tissue, AHF abolished the increase in lanthanum-resistant calcium uptake induced in rat aortae by the addition of high K+ or norepinephrine to the incubation media. In a second part of the study, the effect of AHF on blood pressure and in vitro calcium uptake were compared with that of phosphatidylethanolamine (PEA), the probable identity of another endogenous antihypertensive (renin preinhibitor) compound earlier shown to share important functional similarities with AHF. The results reduce the likelihood that the two causal agents are identical. The AHF produced a significant (75 Torr, 1 Torr = 133.32 Pa) fall in the systolic blood pressure (SBP) of spontaneously hypertensive rats within 24 h following injection, whereas PEA had no effect on the SBP in this model. Both AHF and PEA reduced the resting in vitro uptake of "lanthanum-resistant" calcium in rat aortic segments. However, the AHF effect was significantly greater than PEA at each concentration studied.

Effects of Chronic Administration of Sarpogrelate on Systolic Blood Pressure of Spontaneously Hypertensive Rats: Comparison with Quinapril

Pharmacology ◽  
2002 ◽  
Vol 64 (2) ◽  
pp. 71-75 ◽  
Author(s):  
Yuki Setoguchi ◽  
Toshio Ohnuki ◽  
Mamunur Rashid ◽  
Takashi Nakamura ◽  
Kaoru Hattori ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Chronic Administration ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive

Thermal stress elevates the systolic blood pressure of spontaneously hypertensive rats

Life Sciences ◽  
1978 ◽  
Vol 22 (4) ◽  
pp. 359-362 ◽  
Author(s):  
Terence T. Yen ◽  
Donovan V. Pearson ◽  
Carroll E. Powell ◽  
Gerald L. Kirschner
Keyword(s):  
Blood Pressure ◽  
Thermal Stress ◽  
Systolic Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive
Sign in / Sign up

Export Citation Format

Share Document