Effect of almitrine on renal sodium excretion in chemoreceptor denervated spontaneously hypertensive rats.

The effect of almitrine on urinary sodium excretion was investigated in conscious carotid body-, sino-aortic- and sham-denervated SHR. The animals were kept singly in metabolic cages and had free access to food and tap water. Oral application of almitrine (0.5 mg/kg bwt) during five days induced a twofold natriuresis in sham-operated rats. The first natriuretic response on the fourth day of almitrine treatment was observed in animals of all groups indicating that this effect is not chemoreceptor mediated. The second natriuresis seen on the sixth day of the post-treatment period in both sino-aortic and sham-operated SHR but not in the carotid-body denervated rats does not permit clear conclusions to be drawn. We tend to assume that the natriuretic action of almitrine is not chemoreceptor mediated in conscious SHR.