Effects of digoxin-specific antibody Fab fragment (Digibind) on blood pressure and renal water-sodium metabolism in 5/6 reduced renal mass hypertensive rats.

Abstract

The importance of increased endogenous digitalis-like factor (EDLF) in volume-expanded hypertension has been generally agreed. To further clarify the role of EDLF on the development of hypertension and renal water-sodium handling in 5/6 reduced renal mass hypertensive rats (RRM), we studied the effects of acute administration of digoxin-specific antibody Fab fragment (Digibind) in the early phase and the chronic phase of hypertension in RRM. RRM and sham-operated rats were given 1% saline for 1 or 4 weeks. RRM were injected Digibind (60 mg/kg) or vehicle (0.9% saline) intravenously in the first or fourth week under thiobutabarbital anesthesia. All sham-operated rats were administered Digibind under the same condition. Digibind altered neither blood pressure, heart rate, urine volume, nor urinary sodium excretion in sham-operated rats. However, Digibind produced a gradual but significant decline in mean arterial pressure to the level slightly above that in sham-operated rats from 153 +/- 5 to 131 +/- 5 mm Hg in the first week and from 181 +/- 6 to 129 +/- 4 mm Hg in the fourth week without any significant change in heart rate. The decrease in mean arterial pressure at 160 min after Digibind administration in the fourth week (-48 +/- 5 mm Hg) was greater than that in the first week (-22 +/- 4 mm Hg). No differences were observed in urine volume, urinary sodium excretion, or plasma norepinephrine concentration between Digibind and vehicle-treated RRM in either week. These data suggest that EDLF would contribute to both the early and chronic phase in the development of hypertension in RRM.

• Authors: J Kaide, N Ura, T Torii, M Nakagawa, T Takada, K Shimamoto
• Journal: American journal of hypertension (Am J Hypertens) Vol. 12 Issue 6 Pg. 611-9 (Jun 1999) ISSN: 0895-7061 [Print] United States
• PMID: 10371371 (Publication Type: Journal Article)

Chemical References

• Cardenolides
• Immunoglobulin Fab Fragments
• Saponins
• digoxin antibodies Fab fragments
• digoxin-like factors
• Digoxin
• Sodium
• Norepinephrine

Topics

• Animals
• Blood Pressure (drug effects)
• Body Water (metabolism)
• Cardenolides
• Digoxin (immunology)
• Heart Rate (drug effects)
• Hypertension, Renal (metabolism)
• Immunoglobulin Fab Fragments (administration & dosage, pharmacology)
• Injections, Intravenous
• Kidney (drug effects, metabolism, physiology)
• Male
• Norepinephrine (blood)
• Rats
• Rats, Sprague-Dawley
• Renal Circulation (drug effects)
• Saponins (metabolism)
• Sodium (urine)