S. Holmer et al., ROLE OF RENAL NERVES FOR THE EXPRESSION OF RENIN IN ADULT-RAT KIDNEY, The American journal of physiology, 266(5), 1994, pp. 60000738-60000745
Utilizing a combination of mechanical and chemical unilateral denervat
ion, we have examined the relevance of renal innervation for the expre
ssion of renin in kidneys of adult rats. Renal denervation led to a re
duction by 57 +/- 4% of renin-containing areas in denervated kidneys a
s quantitated by morphometry of kidney sections immunoreactive against
a polyclonal antirenin antibody. Preprorenin mRNA content in the dene
rvated kidneys fell to 46 +/- 7% of the contralateral innervated kidne
ys. Treatment of rats with the beta(1)-adrenoreceptor antagonist metop
rolol (100 mg. kg(-1). day(-1)) for 2 days decreased renal renin mRNA
levels to 71% of control levels. Unilateral renal denervation led to a
further decrease of renin mRNA levels also in metoprolol-treated anim
als to 60% of the values found in the contralateral kidneys. Hypotensi
ve hemorrhage led to a 1.4-fold increase of renin mRNA in the kidneys
of sham-treated animals. In unilaterally denervated rats renin mRNA in
creased to levels similar to those in sham-operated animals in both de
nervated and in contralateral innervated kidneys in response to bleedi
ng. As a consequence, the ratio of abundance of renin mRNA in the dene
rvated to the innervated kidneys rose to 86 +/- 7%. Pretreatment of th
e animals with metoprolol, on the other hand, prevented the rise of re
nin mRNA in response to hypotensive hemorrhage. Our findings suggest t
hat in the adult organism renal neural input significantly contributes
to the expression of renin under basal conditions, while it appears t
o be of less importance for stimulation of renin gene expression by se
vere blood loss.