Benign and malignant hypertension after adrenal enucleation in the rat. Relationship to salt intake, response to hydrochlorothiazide, and similarity to essential hypertension

Biochemical interaction of salt sensitivity: a key player for the development of essential hypertension

Worldwide, more than 1 billion people have elevated blood pressure, with up to 45% of adults affected by the disease. In 2016 the global health study report on patients from 67 countries was released in Lancet, which identified hypertension as the world's leading cause for death and disability-adjusted years since 1990. This paper aims to analyze the pathophysiological connection between hemodynamic inflammatory reactions through sodium balance, salt sensitivity, and potential pathophysiological reactions. Besides, we explore how sodium consumption enhances the expression of transient receptor potential channel 3 (TrpC3) mRNA and facilitates the release of calcium inside immune cell groups, together with elevated blood pressure in essential hypertensive patients.

Mineralocorticoid activity of 19-nor-DOC and 19-OH-DOC in toad bladder

Adrenal enucleation is followed by a period of increased sodium reabsorption thought to be due to excess mineralocorticoid activity. However, it has not been demonstrated that increased production of any known mineralocorticoid accounts for this antinatriuresis. Recently, 19-hydroxydeoxycorticosterone (19-OH-DOC) was found in incubates of regenerating adrenal capsules 3-4 days postenucleation and 19-nordeoxycorticosterone (19-nor-DOC) was identified in the urine of rats with regenerating adrenals. Because it was possible that these hormones might play a role in the sodium retention after adrenal enucleation, we compared the mineralocorticoid activity of these steroids to aldosterone using the toad bladder. Using short-circuit current as a measure of sodium transport, we found that 19-OH-DOC (10(-8) M) had no significant effect on sodium transport. However, 19-nor-DOC (10(-8) M) increased sodium transport to a degree not different from aldosterone (10(-8) M). Furthermore, the onset of action, duration of activity, and inhibition of effect of 19-nor-DOC by spironolactone were not different from that of aldosterone. We conclude that 19-nor-DOC exhibits a significant effect on sodium transport and thus has the potential to play a role in the sodium retention following adrenal enucleation. Under the conditions of these studies, 19-OH-DOC exhibited no effect on sodium transport.

Sodium balance after adrenal enucleation

To better define the relationship between adrenal enucleation (AE), sodium retention and adrenal regeneration hypertension (ARH), we measured daily sodium balance in rats after bilateral adrenal enucleation with (AEN) and without uninephrectomy (AE), and before and after development of ARH, along with the appropriate control groups. We found that both AE and AEN groups retained sodium during 7 days after surgery; AE 1.16 +/- 0.24 and AEN 1.32 +/- 0.33 meq/100 g body wt. Sham-operated, uninephrectomized rats and AE rats treated with spironolactone were in zero sodium balance. In the AEN rats after the development of ARH (BP greater than 150 Torr), zero sodium balance was also noted. Only AEN rats developed hypertension while sham-operated, uninephrectomized rats and AE rats with both kidneys remained normotensive for 28 wk. In summary, we have demonstrated that for 1 wk after AE, rats are in positive sodium balance and this is reversed by spironolactone but not by uninephrectomy.

Methylandrostenediol hypertension induced without salt excess: observations on organ changes and serum composition

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