Prevention of reflex natriuresis after acute unilateral nephrectomy by neonatal administration of MSG

Journal Article · Sun Feb 01 00:00:00 EST 1987 · Am. J. Physiol.; (United States)

OSTI ID:5353585

Lin, S Y; Wiedemann, E; Deschepper, C F; Alper, R H; Humphreys, M H

Acute unilateral nephrectomy (AUN) results in natriuresis from the remaining kidney through reflex pathways involving the central nervous system and requiring an intact pituitary gland. The natriuresis is accompanied by an increase in the plasma concentration of a peptide or peptides derived from the N-terminal fragment (NTF) of proopiomelanocortin. The authors measured plasma immunoreactive NTF-like material (IR-NTF) by radioimmunoassay, before and after AUN in control rats and rats treated neonatally with monosodium glutamate (MSG), a procedure that produces neuroendocrine dysfunction by destroying cell bodies in the hypothalamic arcuate nucleus, median eminence, and other brain regions. In control rats, IR-NTF increased from 85.8 +/- 54.9 (SD) to 207 +/- 98.1 fmol/ml after AUN as sodium excretion (U/sub Na/V) doubled. In MSG-treated rats, AUN produced no change in plasma IR-NTF concentration, nor did U/sub Na/V increase. Tissue content of IR-NTF was reduced in the arcuate nucleus and anterior lobe of pituitaries from MSG-treated rats compared with controls, but was no different in the neurointermediate lobe. These results indicate that the hypothalamic lesion produced by neonatal administration of MSG prevents both the increase in plasma IR-NTF concentration and the natruiuresis after AUN, and therefore lend further support to the concept of a casual relationship between these two consequences of AUN.

• Research Organization: Univ. of California, San Francisco
• OSTI ID: 5353585
• Journal Information: Am. J. Physiol.; (United States), Vol. 252:2
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
KIDNEYS
PHYSIOLOGY
PEPTIDES
RADIOIMMUNOASSAY
SODIUM COMPOUNDS
EXCRETION
CATIONS
GLUTAMIC ACID
NEONATES
NEPHRECTOMY
RATS
ALKALI METAL COMPOUNDS
AMINO ACIDS
ANIMALS
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CHARGED PARTICLES
CLEARANCE
IMMUNOASSAY
IMMUNOLOGY
IONS
ISOTOPE APPLICATIONS
MAMMALS
MEDICINE
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RADIOASSAY
RADIOIMMUNOLOGY
RODENTS
SURGERY
TRACER TECHNIQUES
VERTEBRATES
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