Acute hypocapnia blunts natriuretic and diuretic effects of atrial natriuretic factor in rats

Y. Mimura; A. A. Khraibi; D. M. Heublein; F. G. Knox

doi:10.1152/ajpregu.1994.266.5.r1503

Acute hypocapnia blunts natriuretic and diuretic effects of atrial natriuretic factor in rats

Y. Mimura, A. A. Khraibi, D. M. Heublein, F. G. Knox

College of Medicine and Health Sciences

Mayo Clinic

Research output: Contribution to journal › Article › peer-review

5 Scopus citations

Abstract

Recent studies suggest that the autonomic nervous system, when activated by respiratory alkalosis, may attenuate the renal effects of atrial natriuretic factor (ANF). We evaluated the renal responses to infusion of ANF during acute exposure to hypocapnia in the presence or absence of the renal nerves in anesthetized rats. In this study, renal function during hypocapnia was assessed and was compared with renal function during normocapnia produced by normal ventilation as well as by hyperventilation. Rats were divided into three experimental groups (n = 8): 1) a normally ventilated normocapnic (NV- N) (control) group; 2) a hyperventilated normocapnic (HV-N) group; and 3) a hyperventilated hypocapnic (HV-H) group. The innervated (Inn) right kidney served as a control for the contralateral denervated (DNX) kidney. In Inn and DNX kidneys of HV-H rats, an infusion of ANF (12 μg · kg^-1 · h^-1) produced a smaller increase in urine flow rate (ΔV̇: 9.8 ± 3.9 and 1.3 ± 4.2 μl/min) and in fractional Na excretion (ΔFE(Na): 1.35 ± 0.52 and 0.73 ± 0.58%) compared with NV-N rats (ΔV̇: 37.6 ± 4.9 and 59.9 ± 9.7 μl/min; ΔFE(Na): 3.24 ± 0.37 and 3.88 ± 0.65%). No differences were observed in ΔV̇ and ΔFE(Na) in Inn kidney between HV-H and HV-N groups; however, the attenuated natriuretic and diuretic responses to ANF in DNX kidney of HV-H rats were also observed in comparison with HV-N rats (ΔV̇: 27.4 ± 4.3 μl/min; ΔFE(Na): 2.94 ± 0.48%). ANF induced natriuresis in DNX kidney to the same degree in NV-N and HV-N rats. In summary, we find that 1) hyperventilation in the absence of hypocapnia results in a blunted natriuresis to ANF infusion that is restored by renal denervation; and 2) hypocapnia attenuates the natriuretic and diuretic responses to ANF in the presence and absence of the renal nerves. These data suggest that the renal sympathetic nervous system does not modulate the renal actions of ANF during hypocapnia but plays an important role during normocapnia.

Original language	British English
Pages (from-to)	R1503-R1509
Journal	American Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume	266
Issue number	5 35-5
DOIs	https://doi.org/10.1152/ajpregu.1994.266.5.r1503
State	Published - 1994

Keywords

hyperventilation
renal denervation
renal function
renal nerves

Access to Document

10.1152/ajpregu.1994.266.5.r1503

Cite this

@article{e62a6f97452747c09b0d7c1efccaed1c,

title = "Acute hypocapnia blunts natriuretic and diuretic effects of atrial natriuretic factor in rats",

abstract = "Recent studies suggest that the autonomic nervous system, when activated by respiratory alkalosis, may attenuate the renal effects of atrial natriuretic factor (ANF). We evaluated the renal responses to infusion of ANF during acute exposure to hypocapnia in the presence or absence of the renal nerves in anesthetized rats. In this study, renal function during hypocapnia was assessed and was compared with renal function during normocapnia produced by normal ventilation as well as by hyperventilation. Rats were divided into three experimental groups (n = 8): 1) a normally ventilated normocapnic (NV- N) (control) group; 2) a hyperventilated normocapnic (HV-N) group; and 3) a hyperventilated hypocapnic (HV-H) group. The innervated (Inn) right kidney served as a control for the contralateral denervated (DNX) kidney. In Inn and DNX kidneys of HV-H rats, an infusion of ANF (12 μg · kg-1 · h-1) produced a smaller increase in urine flow rate (Δ{\.V}: 9.8 ± 3.9 and 1.3 ± 4.2 μl/min) and in fractional Na excretion (ΔFE(Na): 1.35 ± 0.52 and 0.73 ± 0.58%) compared with NV-N rats (Δ{\.V}: 37.6 ± 4.9 and 59.9 ± 9.7 μl/min; ΔFE(Na): 3.24 ± 0.37 and 3.88 ± 0.65%). No differences were observed in Δ{\.V} and ΔFE(Na) in Inn kidney between HV-H and HV-N groups; however, the attenuated natriuretic and diuretic responses to ANF in DNX kidney of HV-H rats were also observed in comparison with HV-N rats (Δ{\.V}: 27.4 ± 4.3 μl/min; ΔFE(Na): 2.94 ± 0.48%). ANF induced natriuresis in DNX kidney to the same degree in NV-N and HV-N rats. In summary, we find that 1) hyperventilation in the absence of hypocapnia results in a blunted natriuresis to ANF infusion that is restored by renal denervation; and 2) hypocapnia attenuates the natriuretic and diuretic responses to ANF in the presence and absence of the renal nerves. These data suggest that the renal sympathetic nervous system does not modulate the renal actions of ANF during hypocapnia but plays an important role during normocapnia.",

keywords = "hyperventilation, renal denervation, renal function, renal nerves",

author = "Y. Mimura and Khraibi, {A. A.} and Heublein, {D. M.} and Knox, {F. G.}",

year = "1994",

doi = "10.1152/ajpregu.1994.266.5.r1503",

language = "British English",

volume = "266",

pages = "R1503--R1509",

journal = "American Journal of Physiology - Regulatory Integrative and Comparative Physiology",

issn = "0363-6119",

publisher = "American Physiological Society",

number = "5 35-5",

}

TY - JOUR

T1 - Acute hypocapnia blunts natriuretic and diuretic effects of atrial natriuretic factor in rats

AU - Mimura, Y.

AU - Khraibi, A. A.

AU - Heublein, D. M.

AU - Knox, F. G.

PY - 1994

Y1 - 1994

N2 - Recent studies suggest that the autonomic nervous system, when activated by respiratory alkalosis, may attenuate the renal effects of atrial natriuretic factor (ANF). We evaluated the renal responses to infusion of ANF during acute exposure to hypocapnia in the presence or absence of the renal nerves in anesthetized rats. In this study, renal function during hypocapnia was assessed and was compared with renal function during normocapnia produced by normal ventilation as well as by hyperventilation. Rats were divided into three experimental groups (n = 8): 1) a normally ventilated normocapnic (NV- N) (control) group; 2) a hyperventilated normocapnic (HV-N) group; and 3) a hyperventilated hypocapnic (HV-H) group. The innervated (Inn) right kidney served as a control for the contralateral denervated (DNX) kidney. In Inn and DNX kidneys of HV-H rats, an infusion of ANF (12 μg · kg-1 · h-1) produced a smaller increase in urine flow rate (ΔV̇: 9.8 ± 3.9 and 1.3 ± 4.2 μl/min) and in fractional Na excretion (ΔFE(Na): 1.35 ± 0.52 and 0.73 ± 0.58%) compared with NV-N rats (ΔV̇: 37.6 ± 4.9 and 59.9 ± 9.7 μl/min; ΔFE(Na): 3.24 ± 0.37 and 3.88 ± 0.65%). No differences were observed in ΔV̇ and ΔFE(Na) in Inn kidney between HV-H and HV-N groups; however, the attenuated natriuretic and diuretic responses to ANF in DNX kidney of HV-H rats were also observed in comparison with HV-N rats (ΔV̇: 27.4 ± 4.3 μl/min; ΔFE(Na): 2.94 ± 0.48%). ANF induced natriuresis in DNX kidney to the same degree in NV-N and HV-N rats. In summary, we find that 1) hyperventilation in the absence of hypocapnia results in a blunted natriuresis to ANF infusion that is restored by renal denervation; and 2) hypocapnia attenuates the natriuretic and diuretic responses to ANF in the presence and absence of the renal nerves. These data suggest that the renal sympathetic nervous system does not modulate the renal actions of ANF during hypocapnia but plays an important role during normocapnia.

AB - Recent studies suggest that the autonomic nervous system, when activated by respiratory alkalosis, may attenuate the renal effects of atrial natriuretic factor (ANF). We evaluated the renal responses to infusion of ANF during acute exposure to hypocapnia in the presence or absence of the renal nerves in anesthetized rats. In this study, renal function during hypocapnia was assessed and was compared with renal function during normocapnia produced by normal ventilation as well as by hyperventilation. Rats were divided into three experimental groups (n = 8): 1) a normally ventilated normocapnic (NV- N) (control) group; 2) a hyperventilated normocapnic (HV-N) group; and 3) a hyperventilated hypocapnic (HV-H) group. The innervated (Inn) right kidney served as a control for the contralateral denervated (DNX) kidney. In Inn and DNX kidneys of HV-H rats, an infusion of ANF (12 μg · kg-1 · h-1) produced a smaller increase in urine flow rate (ΔV̇: 9.8 ± 3.9 and 1.3 ± 4.2 μl/min) and in fractional Na excretion (ΔFE(Na): 1.35 ± 0.52 and 0.73 ± 0.58%) compared with NV-N rats (ΔV̇: 37.6 ± 4.9 and 59.9 ± 9.7 μl/min; ΔFE(Na): 3.24 ± 0.37 and 3.88 ± 0.65%). No differences were observed in ΔV̇ and ΔFE(Na) in Inn kidney between HV-H and HV-N groups; however, the attenuated natriuretic and diuretic responses to ANF in DNX kidney of HV-H rats were also observed in comparison with HV-N rats (ΔV̇: 27.4 ± 4.3 μl/min; ΔFE(Na): 2.94 ± 0.48%). ANF induced natriuresis in DNX kidney to the same degree in NV-N and HV-N rats. In summary, we find that 1) hyperventilation in the absence of hypocapnia results in a blunted natriuresis to ANF infusion that is restored by renal denervation; and 2) hypocapnia attenuates the natriuretic and diuretic responses to ANF in the presence and absence of the renal nerves. These data suggest that the renal sympathetic nervous system does not modulate the renal actions of ANF during hypocapnia but plays an important role during normocapnia.

KW - hyperventilation

KW - renal denervation

KW - renal function

KW - renal nerves

UR - http://www.scopus.com/inward/record.url?scp=0028245766&partnerID=8YFLogxK

U2 - 10.1152/ajpregu.1994.266.5.r1503

DO - 10.1152/ajpregu.1994.266.5.r1503

M3 - Article

C2 - 8203627

AN - SCOPUS:0028245766

SN - 0363-6119

VL - 266

SP - R1503-R1509

JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology

JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology

IS - 5 35-5

ER -

Acute hypocapnia blunts natriuretic and diuretic effects of atrial natriuretic factor in rats

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this