Role of Adrenal Cortical Activity in Experimental Hypertension Induced by Bilateral Nephrectomy in the Dog

Excess sympathetic nervous system activity (SNA) is linked to human essential and experimental hypertension. To test whether sympathetic activation is associated with a model of deoxycorticosterone acetate (DOCA)-salt hypertension featuring two kidneys and a moderate elevation of blood pressure, we measured whole body norepinephrine (NE) spillover as an index of global SNA. Studies were conducted in chronically catheterized male Sprague-Dawley rats drinking water containing 1% NaCl and 0.2% KCl. After a 7-day surgical recovery and a 3-day control period, a DOCA pellet (50 mg/kg) was implanted subcutaneously in one group of rats (DOCA), while the other group underwent sham implantation (Sham). NE spillover was measured on control day 2 and days 7 and 14 after DOCA administration or sham implantation. During the control period, mean arterial pressure (MAP) was similar in Sham and DOCA rats. MAP was significantly increased in the DOCA group compared with the Sham group after DOCA administration ( day 14: Sham = 109 ± 5.3, DOCA = 128 ± 3.6 mmHg). However, plasma NE concentration, clearance, and spillover were not different in the two groups at any time. To determine whether selective sympathetic activation to the kidneys contributes to hypertension development, additional studies were performed in renal denervated (RDX) and sham-denervated (Sham-DX) rats. MAP, measured by radiotelemetry, was similar in both groups during the control and DOCA treatment periods. In conclusion, global SNA is not increased during the development of mild DOCA-salt hypertension, and fully intact renal nerves are not essential for hypertension development in this model.

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Role of TLR4 expression in experimental hypertension

The FASEB Journal ◽

10.1096/fasebj.24.1_supplement.955.7 ◽

2010 ◽

Vol 24 (S1) ◽

Author(s):

Gisele Facholi Bomfim ◽

Rita Tostes ◽

Zuleica Fortes ◽

Maria Helena Catelli Carvalho

Keyword(s):

Experimental Hypertension ◽

Tlr4 Expression

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The Role of Cortical Activity in Experience-Dependent Potentiation and Depression of Sensory Responses in Rat Barrel Cortex

Journal of Neuroscience ◽

10.1523/jneurosci.21-11-03881.2001 ◽

2001 ◽

Vol 21 (11) ◽

pp. 3881-3894 ◽

Cited By ~ 37

Author(s):

Helen Wallace ◽

Stanislaw Glazewski ◽

Katherine Liming ◽

Kevin Fox

Keyword(s):

Barrel Cortex ◽

Cortical Activity ◽

Sensory Responses

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Role of medullary emetic chemoreceptor trigger zone (CT zone) in postnephrectomy vomiting in dogs

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1959.197.4.850 ◽

1959 ◽

Vol 197 (4) ◽

pp. 850-852 ◽

Cited By ~ 15

Author(s):

H. L. Borison ◽

L. M. Hebertson

Keyword(s):

Spinal Cord ◽

Serum Sodium ◽

Guanidine Hydrochloride ◽

Rapid Decline ◽

Bilateral Nephrectomy ◽

Sodium Potassium ◽

Chemoreceptor Trigger Zone ◽

Serum Chloride ◽

Trigger Zone

Latencies for vomiting following bilateral nephrectomy in control dogs, after gut denervation by transthoracic vagotomy and spinal cord transection at T4, and after ineffective ablation of the CT zone, were all within a range of 16–48 hours. By contrast, in dogs with effective lesions of the CT zone, the latency for vomiting after nephrectomy was prolonged to a range of 54–147 hours and two dogs died after 5 and 6 days, respectively, without vomiting. Chlorpromazine and morphine did not prolong the latency for vomiting after nephrectomy. Guanidine hydrochloride, 75 mg/kg i.v., evoked vomiting in all of seven control dogs, but only in one of nine dogs with effective lesions of the CT zone. Except for a more rapid decline of serum chloride in control dogs, serum sodium, potassium, bicarbonate and blood urea nitrogen followed the same pattern after nephrectomy in control and CT-zone ablated dogs.

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Role of Sympathetic Nervous System in Experimental Hypertension and Diabetes Mellitus

Clinical and Experimental Hypertension ◽

10.3109/10641969909068653 ◽

1999 ◽

Vol 21 (1-2) ◽

pp. 95-112 ◽

Cited By ~ 9

Author(s):

C. L. Kaul

Keyword(s):

Diabetes Mellitus ◽

Nervous System ◽

Sympathetic Nervous System ◽

Experimental Hypertension ◽

Sympathetic Nervous

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Stimulation of aldosterone biosynthesis by sodium sequestration: role of angiotensin II

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1982.243.6.e450 ◽

1982 ◽

Vol 243 (6) ◽

pp. E450-E457

Author(s):

J. Muller ◽

E. G. Lund ◽

L. Hofstetter ◽

D. B. Brunner ◽

P. Haldy

Keyword(s):

Angiotensin Ii ◽

Enzyme Inhibitor ◽

Zona Glomerulosa ◽

High Dose ◽

Converting Enzyme ◽

Bilateral Nephrectomy ◽

Stimulatory Action ◽

Sodium Sequestration ◽

Stimulation Of

The role of angiotensin II in the stimulation of aldosterone biosynthesis by sodium sequestration in potassium-deficient rats was assessed by experiments involving 1-day angiotensin II infusion, converting enzyme inhibition, and bilateral nephrectomy. In intact rats, only an extremely high dose of exogenous angiotensin II imitated the stimulatory effects of polyethylene glycol-induced edema on the conversions of deoxycorticosterone and corticosterone to 18-hydroxycorticosterone and aldosterone. Treatment with the converting enzyme inhibitor captopril as well as bilateral nephrectomy blocked the aldosterone-stimulating action of edema. This inhibition was prevented by the simultaneous infusion of angiotensin II in captopril-treated rats but not in nephrectomized animals. According to these results, angiotensin II is an essential mediator in the stimulation of aldosterone biosynthesis by sodium sequestration. However, the role of the kidneys appears to be twofold. First, they act through the secretion of renin. In addition, a second yet unknown kidney factor is necessary for a full response of the zona glomerulosa to the stimulatory action of angiotensin II.

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The role of cognitive reserve on prefrontal and premotor cortical activity in visuo-motor response tasks in healthy old adults

Neurobiology of Aging ◽

10.1016/j.neurobiolaging.2020.06.002 ◽

2020 ◽

Vol 94 ◽

pp. 185-195

Author(s):

Federico Quinzi ◽

Marika Berchicci ◽

Valentina Bianco ◽

Gloria Di Filippo ◽

Rinaldo Livio Perri ◽

...

Keyword(s):

Motor Response ◽

Cognitive Reserve ◽

Cortical Activity ◽

Old Adults

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The ANG-(1–7)/ACE2/mas axis in the regulation of nephron function

AJP Renal Physiology ◽

10.1152/ajprenal.00110.2010 ◽

2010 ◽

Vol 298 (6) ◽

pp. F1297-F1305 ◽

Cited By ~ 96

Author(s):

Carlos M. Ferrario ◽

Jasmina Varagic

Keyword(s):

Angiotensin Converting Enzyme ◽

Renin Angiotensin System ◽

Therapeutic Interventions ◽

Experimental Hypertension ◽

Converting Enzyme ◽

Angiotensin System ◽

Angiotensin Converting Enzyme 2 ◽

Renin Angiotensin ◽

A Site

The study of experimental hypertension and the development of drugs with selective inhibitory effects on the enzymes and receptors constituting the components of the circulating and tissue renin-angiotensin systems have led to newer concepts of how this system participates in both physiology and pathology. Over the last decade, a renewed emphasis on understanding the role of angiotensin-(1–7) and angiotensin-converting enzyme 2 in the regulation of blood pressure and renal function has shed new light on the complexity of the mechanisms by which these components of the renin angiotensin system act in the heart and in the kidneys to exert a negative regulatory influence on angiotensin converting enzyme and angiotensin II. The vasodepressor axis composed of angiotensin-(1–7)/angiotensin-converting enzyme 2/mas receptor emerges as a site for therapeutic interventions within the renin-angiotensin system. This review summarizes the evolving knowledge of the counterregulatory arm of the renin-angiotensin system in the control of nephron function and renal disease.

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