Ovine fetal renal and hormonal responses to changes in plasma epinephrine.
Circulating epinephrine alters atrial natriuretic factor (ANF) and arginine vasopressin (AVP) secretion, and all three hormones influence renal function. To quantify the relationships among fetal plasma epinephrine levels, fetal ANF and AVP secretion, and fetal renal function, six chronically catheterized fetal lambs (132 +/- 1 days gestation) received successive 40-min epinephrine infusions (0.1, 0.4, and 1.8 micrograms.min-1.kg-1). The second epinephrine infusion dose evoked significant increases in urine flow (V; 0.7 +/- 0.2 to 1.2 +/- 0.2 ml/min), free water clearance (CH2O; 0.3 +/- 0.1 to 0.7 +/- 0.1 ml/min), glomerular filtration rate (GFR; 3.9 +/- 0.7 to 5.4 +/- 0.8 ml/min), fractional water excretion (V/CH2O; 19 +/- 3 to 25 +/- 2%), mean arterial pressure (MAP; 45 +/- 3 to 51 +/- 4 mmHg), and a 94% increase in plasma ANF levels. A fourfold increase in the infusion dose significantly increased osmolar clearance (0.3 +/- 0.1 to 0.6 +/- 0.1 ml/min), sodium excretion (28 +/- 8 to 53 +/- 13 mueq/min), and plasma AVP levels (2.4 +/- 0.5 to 6.4 +/- 2.4 pg/ml) with no additional effect on V, CH2O, GFR, V/GFR, MAP, or plasma ANF levels. Urine osmolality and fractional sodium excretion did not change in response to epinephrine infusion. Our results demonstrate that epinephrine infusion stimulates fetal ANF secretion and to a lesser extent AVP secretion and significantly influences fetal renal function.
Ervin
M G
MG
Department of Obstetrics and Gynecology, Harbor-UCLA Medical Center, School of Medicine, Torrance 90509.
Castro
R
R
Sherman
D J
DJ
Ross
M G
MG
Padbury
J F
JF
Leake
R D
RD
Fisher
D A
DA
D000818:Animals; D001127:Arginine Vasopressin / Q000097:blood* / Q000502:physiology; D009320:Atrial Natriuretic Factor / Q000097:blood* / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005260:Female; D005333:Fetus / Q000378:metabolism* / Q000502:physiology; D005919:Glomerular Filtration Rate / Q000187:drug effects / Q000502:physiology; D007262:Infusions, Intravenous; D007668:Kidney / Q000196:embryology / Q000378:metabolism* / Q000502:physiology; D011247:Pregnancy; D012039:Regional Blood Flow; D012756:Sheep; D012964:Sodium / Q000652:urine
D001127:Arginine Vasopressin; D009320:Atrial Natriuretic Factor; D012964:Sodium; D004837:Epinephrine