title: Effects of acyclovir on renal function.
abstract: The renal effects of acyclovir (100 mg/kg body weight i.p. for 7 days) were studied in rats. All animals became polyuric and presented an increase in blood urea nitrogen and fractional excretion of sodium and potassium. During hypotonic saline infusion, the acyclovir-treated rats showed higher distal fractional delivery compared to normal rats (27.8 +/- 4.7 vs. 11.3 +/- 0.9%, p less than 0.01) and a lower ratio of free-water clearance to distal sodium delivery (33.5 +/- 7.8 vs. 57.2 +/- 3.9%, p less than 0.02). Following hypertonic saline infusion, the ratio of osmolar to inulin clearance was higher in acyclovir rats (47.8 +/- 7.4%) than in normal rats (27.0 +/- 4.8%), whereas the ratio of free-water reabsorption to osmolar clearance was lower in the acyclovir rats (13.6 +/- 4.6 vs. 38.2 +/- 3.2%, p less than 0.01). These findings suggest an effect of acyclovir on the proximal tubule, thick ascending limb and/or inner medullary collecting duct (IMCD). In vitro measurements of 3H2O permeability of perfused IMCD of normal rats showed that vasopressin (50 microU/ml) added to the bath increased the diffusional water permeability (43.4 +/- 4.8 vs. 105.6 +/- 9.1 x 10(-5) cm/s), while in acyclovir rats, the control value (58.8 +/- 9.1 x 10(-5) cm/s) did not increase significantly in the presence of vasopressin (71.3 +/- 13.6 x 10(-5) cm/s). These results suggest that high doses of acyclovir produce azotemia and an abnormal function of the proximal tubule and thick ascending limb associated with resistance to vasopressin of the IMCD.
authors.affiliation: Laboratório de Pesquisa Básica, Nefrologia Faculdade de Medicina, Universidade de São Paulo, Brasil.
authors.forename: S B
authors.initials: SB
authors.lastname: Campos
authors.forename: A C
authors.initials: AC
authors.lastname: Seguro
authors.forename: K R
authors.initials: KR
authors.lastname: Cesar
authors.forename: A S
authors.initials: AS
authors.lastname: Rocha
mesh_terms: D000212:Acyclovir / Q000494:pharmacology*; D000818:Animals; D001806:Blood Urea Nitrogen; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007668:Kidney / Q000187:drug effects / Q000502:physiology*; D008297:Male; D010477:Perfusion; D011188:Potassium / Q000652:urine; D051381:Rats; D017208:Rats, Wistar; D012964:Sodium / Q000652:urine; D014667:Vasopressins / Q000494:pharmacology
chemical_list: D014667:Vasopressins; D012964:Sodium; D011188:Potassium; D000212:Acyclovir