Adenosine modulates hypoxia-induced atrial natriuretic peptide release in fetal sheep.
Am J Physiol
; 269(1 Pt 2): H282-7, 1995 Jul.
Article
en En
| MEDLINE
| ID: mdl-7631858
The effects of adenosine on atrial natriuretic peptide (ANP) secretion were determined in chronically catheterized fetal sheep (> 0.8 term). Adenosine was infused into the the right jugular vein for 1 h at 8 +/- 0.4 (5 fetuses), 160 +/- 8 (6 fetuses), and 344 +/- 18 micrograms.min-1.kg estimated fetal wt-1. Fetal arterial blood gases and pH were generally unaffected by adenosine, although mean arterial CO2 tension increased transiently by 2-5 Torr and pH fell progressively during the highest rate of infusion. During the intermediate and high infusion rates, fetal hemoglobin concentrations increased by 11-13% and mean fetal heart rate rose by 18% from a control value of approximately 167 beats/min. Mean arterial pressure was not affected during adenosine infusion. Adenosine significantly increased fetal plasma ANP levels, with maximum concentrations 1.80, 2.36, and 2.51 times greater than control means (142-166 pg/ml) for the respective infusion rates of 8, 160, and 344 micrograms.min-1.kg estimated fetal wt-1. In seven fetuses, reducing fetal arterial O2 tension by approximately 9-10 Torr from a control of 23 +/- 1.3 Torr increased plasma ANP concentrations approximately 2.4 times the control mean of 176 pg/min. Adenosine-receptor blockade with 8-(p-sulfophenyl)-theophylline reduced by 50% the maximum hypoxia-induced rise in plasma ANP concentrations. It is concluded that adenosine causes a dose-dependent rise in fetal plasma ANP concentrations and modulates fetal ANP release during hypoxia.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Adenosina
/
Factor Natriurético Atrial
/
Sangre Fetal
/
Hipoxia
Límite:
Animals
Idioma:
En
Revista:
Am J Physiol
Año:
1995
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos