TY - JOUR
T1 - Development of fetal vascular responses to endothelin-1 and acetylcholine in the sheep
AU - Docherty, Cheryl C.
AU - Kalmar-Nagy, Judit
AU - Engelen, Marc
AU - Nathanielsz, Peter W.
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2001/2
Y1 - 2001/2
N2 - Responses to K+, endothelin-1 (ET-1), and acetylcholine (ACh) of isolated adrenal, femoral, middle cerebral, and renal arteries from fetal [110-145 days gestational age (dGA, term ∼148 dGA)] and 0- to 24-h newborn (NB) lambs were evaluated using the technique of wire myography. Responses at distinct developmental ages for each vascular bed were compared. In all arteries sensitivity to K+-induced vasoconstriction was similar at all fetal age points examined. In contrast, sensitivity to ET-1 increased with increasing fetal age in arteries from all vascular beds. The magnitude of the maximal vasoconstriction was positively correlated with GA for K+ in adrenal, femoral, and cerebral arteries and for ET-1 in femoral, cerebral, and renal arteries. Cerebral arteries showed a greater sensitivity when compared with the other systemic arteries to K+ and ET-1 at all fetal ages and to K+ in NB. ACh evoked relaxatory responses in fetal and NB femoral and adrenal arteries. However, renal arteries relaxed comparatively less in response to ACh, and no vasodilation was noted in middle cerebral arteries at any age points examined. For femoral arteries ACh-induced vasorelaxation decreased with increasing GA but was restored in arteries from NB lambs. In summary, the responsiveness of isolated resistance arteries varies with developmental age in the fetal and perinatal sheep and these effects are both agonist and vascular bed specific. The augmented sensitivity in response to ET-1 of middle cerebral compared with other systemic arteries may reflect the importance of cerebral blood flow control during this critical developmental period.
AB - Responses to K+, endothelin-1 (ET-1), and acetylcholine (ACh) of isolated adrenal, femoral, middle cerebral, and renal arteries from fetal [110-145 days gestational age (dGA, term ∼148 dGA)] and 0- to 24-h newborn (NB) lambs were evaluated using the technique of wire myography. Responses at distinct developmental ages for each vascular bed were compared. In all arteries sensitivity to K+-induced vasoconstriction was similar at all fetal age points examined. In contrast, sensitivity to ET-1 increased with increasing fetal age in arteries from all vascular beds. The magnitude of the maximal vasoconstriction was positively correlated with GA for K+ in adrenal, femoral, and cerebral arteries and for ET-1 in femoral, cerebral, and renal arteries. Cerebral arteries showed a greater sensitivity when compared with the other systemic arteries to K+ and ET-1 at all fetal ages and to K+ in NB. ACh evoked relaxatory responses in fetal and NB femoral and adrenal arteries. However, renal arteries relaxed comparatively less in response to ACh, and no vasodilation was noted in middle cerebral arteries at any age points examined. For femoral arteries ACh-induced vasorelaxation decreased with increasing GA but was restored in arteries from NB lambs. In summary, the responsiveness of isolated resistance arteries varies with developmental age in the fetal and perinatal sheep and these effects are both agonist and vascular bed specific. The augmented sensitivity in response to ET-1 of middle cerebral compared with other systemic arteries may reflect the importance of cerebral blood flow control during this critical developmental period.
KW - Arteries
KW - Fetal sheep
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U2 - 10.1152/ajpregu.2001.280.2.r554
DO - 10.1152/ajpregu.2001.280.2.r554
M3 - Article
C2 - 11208587
AN - SCOPUS:0035008751
VL - 280
SP - R554-R562
JO - American Journal of Physiology
JF - American Journal of Physiology
SN - 0363-6119
IS - 2 49-2
ER -