Effect of glucocorticoid deficiency on arterial pressure in conscious spontaneously hypertensive rats. Academic Article uri icon

abstract

  • The effect of selective glucocorticoid or mineralocorticoid deficiency upon arterial pressure was evaluated in unanesthetized adult spontaneously hypertensive rats (SHR). Adrenalectomized SHR were replaced with 6 micrograms/24 h aldosterone (ALDO), 10 microgram/24 h dexamethasone (DEX), or both aldosterone and dexamethasone (ALDO + DEX) by IP osmotic mini-pumps. These were compared to sham-operated SHR (SHAM) and adrenalectomized SHR given no steroid replacement (ADX). Drinking fluid for all groups was 1% NaCl + 2.5% glucose. Six days after adrenalectomy, intra-arterial mean arterial pressure (MAP) fell from 174 +/- 2 to 149 +/- 6 mm Hg in ALDO (n = 8, P less than .01) and from 179 +/- 4 to 125 +/- 4 in ADX (n = 6, P less than .01). In contrast, MAP rose in SHAM from 171 +/- 4 to 179 +/- 5 mm Hg (n = 7, P less than .01), in ALDO + DEX from 161 +/- 3 to 184 +/- 4 mm Hg (n = 7, P less than .01), and in DEX from 162 +/- 2 to 181 +/- 4 mm Hg (n = 7, P less than .01). The results indicate that when diet salt intake is high, glucocorticoid action is necessary for the full expression of hypertension in adult SHR.

publication date

  • January 1, 1989