[Behavior of the lithium excretion fraction in hypertensive patients during variations of sodium intake].
Fractional excretion of lithium (FeLi) is a marker of proximal tubular sodium reabsorption. During different sodium intakes (normal = 120 mEq/day, low = 40 mEq/day and high = 240 mEq/day) fractional lithium excretion was evaluated in essential hypertensive patients (n. 19) and control subjects (n. 5). Our data showed that FeLi was higher in hypertensives than in controls. Dividing hypertensives on the basis of blood-pressure sensitivity, salt resistant patients showed lower FeLi levels as compared to salt sensitive ones. Our findings indicate that proximal tubular sodium reabsorption is decreased in essential hypertension; this behavior is particularly evident in salt sensitive patients, suggesting that factors affecting proximal tubular function are activated in these patients in order to reduce the impairment of renal excretory capability.
Luparini
R L
RL
Istituto di Clinica Medica I, Università degli Studi di Roma La Sapienza.
Montini
A
A
Satira
R
R
Ferri
C
C
Giarrizzo
C
C
Pennacchia
M
M
Germanõ
G
G
Santucci
A
A
D000328:Adult; D001794:Blood Pressure; D004039:Diet, Sodium-Restricted; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension / Q000378:metabolism* / Q000503:physiopathology; D008094:Lithium / Q000652:urine*; D016651:Lithium Carbonate / Q000378:metabolism; D008875:Middle Aged; D012964:Sodium / Q000378:metabolism*; D012982:Sodium, Dietary / Q000008:administration & dosage*
D012982:Sodium, Dietary; D016651:Lithium Carbonate; D008094:Lithium; D012964:Sodium
Comportamento della frazione di escrezione del litio nel paziente iperteso durante variazioni dell'introito sodico.