title: Impaired atrial natriuretic factor systemic clearance contributes to its higher levels in uremia.
abstract: To evaluate the interaction between plasma levels and the systemic uptake of atrial natriuretic factor (ANF) with thyroid hormone levels during acute renal failure (ARF), seven groups of rats were analyzed: Group 1, Controls (C); Group 2, ARF; Group 3, filtering kidney with uremia; Group 4, ARF with thyroxine (T4) supplement (ARF + T4); Group 5, thyroidectomy (Tx); Group 6, ARF on Tx rats (Tx + ARF); Group 7, Tx + ARF supplemented with T4 (Tx + ARF + T4). Plasma creatinine (Cr), urea, T4, blood volume, and ANF were measured; ANF half-life (ANF t1/2; expressed in seconds) was calculated. Rats with ARF developed uremia (Cr, 377 +/- 58 versus 41 +/- 5 mumol/L), significant reduction in T4 (40 +/- 4 versus 89.2 +/- 6 nmol/L). elevation of ANF (287.7 +/- 35 versus 60.9 +/- 8 fmol/mL), and lengthening of ANF t1/2 (69.7 +/- 8 versus 37.2 +/- 6 s) compared with C (P less than 0.01). T4 supplements to ARF rats resulted in a lesser degree of uremia (Cr, 283 +/- 27; P less than 0.05) and normalization of ANF t1/2 (31.4 +/- 5); however, ANF levels remained higher than C (100.4 +/- 11.4 versus 60.9 +/- 8; P less than 0.01). Tx by itself did not change either parameter. The filtering kidney with uremia group developed mild uremia (Cr, 199 +/- 8), T4 fell (58 +/- 8), ANF levels rose (83.4 +/- 5.4), and ANF t1/2 was prolonged (54.5 +/- 12). Tx before ARF doubled the ANF level and lengthened ANF t1/2 similarly than in ARF. T4 addition (Tx + ARF + T4) normalized ANF t1/2 (29.8 +/- 3) in spite of a persistently high ANF (145.7 +/- 21). Blood volume did not change in any group.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Nephrology, Instituto Nacional de Cardiologia Ignacio Chavez, Mexico, D.F.
authors.forename: R
authors.initials: R
authors.lastname: Paniagua
authors.forename: M
authors.initials: M
authors.lastname: Franco
authors.forename: E
authors.initials: E
authors.lastname: Rodriguez
authors.forename: G
authors.initials: G
authors.lastname: Sanchez
authors.forename: G
authors.initials: G
authors.lastname: Morales
authors.forename: J
authors.initials: J
authors.lastname: Herrera-Acosta
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000378:metabolism*; D001693:Biological Transport, Active; D006207:Half-Life; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013965:Thyroidectomy; D013974:Thyroxine / Q000097:blood / Q000494:pharmacology; D014511:Uremia / Q000097:blood / Q000378:metabolism*
chemical_list: D009320:Atrial Natriuretic Factor; D013974:Thyroxine