title: Role of thromboxane in mediating the intrarenal vasoconstriction induced by unmodified stroma free hemoglobin in the isolated perfused rat kidney.
abstract: Unmodified stroma free hemoglobin (SFH) increased renal vascular resistance (RVR) from 4.0 +/- 0.2 to 6.9 +/- 0.9 mmHg/ml/min in control isolated kidneys. In kidneys obtained from rats pretreated with the thromboxane synthetase inhibitor OKY-046 RVR increased from 3.9 +/- 0.3 to 4.8 +/- 0.4 mmHg/ml/min. The percent increase in RVR was greater in response to SFH in control kidneys (67 +/- 14%) than in OKY-046 treated kidneys (23 +/- 7%)(p less than 0.05). SFH resulted in a fall in glomerular filtration rate (GFR) from 0.75 +/- 0.09 to 0.21 +/- 0.04 ml/min in control kidneys while in kidneys from OKY-046 treated rats GFR fell from 0.65 +/- 0.04 to 0.54 +/- 0.06 ml/min. The percent fall in GFR was greater in vehicle treated kidneys (69 +/- 8%) as opposed to OKY-046 treated kidneys (19 +/- 7%)(p less than 0.05). The rate of urinary thromboxane excretion measured before the addition of SFH to the perfusate was 52 pg/min in the control group and 7 pg/min in the OKY-046 treated group(p less than 0.05).
authors.affiliation: Evans Memorial Department of Clinical Research, University Hospital, Boston, MA.
authors.forename: W
authors.initials: W
authors.lastname: Lieberthal
authors.forename: J
authors.initials: J
authors.lastname: LaRaia
authors.forename: C R
authors.initials: CR
authors.lastname: Valeri
mesh_terms: D000818:Animals; D001802:Blood Substitutes / Q000633:toxicity*; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006454:Hemoglobins / Q000633:toxicity*; D066298:In Vitro Techniques; D008297:Male; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D012079:Renal Circulation / Q000187:drug effects* / Q000502:physiology; D013931:Thromboxanes / Q000502:physiology*; D014655:Vascular Resistance / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D001802:Blood Substitutes; D006454:Hemoglobins; D013931:Thromboxanes; C016484:hemoglobin, stroma free