Fetal endocrine responses to prolonged reduced uterine blood flow are altered following bilateral sectioning of the carotid sinus and vagus nerves

in Journal of Endocrinology
Authors:
PE Stein
Search for other papers by PE Stein in
Current site
Google Scholar
PubMed
Close
,
SE White
Search for other papers by SE White in
Current site
Google Scholar
PubMed
Close
,
J Homan
Search for other papers by J Homan in
Current site
Google Scholar
PubMed
Close
,
L Fraher
Search for other papers by L Fraher in
Current site
Google Scholar
PubMed
Close
,
HH McGarrigle
Search for other papers by HH McGarrigle in
Current site
Google Scholar
PubMed
Close
,
MA Hanson
Search for other papers by MA Hanson in
Current site
Google Scholar
PubMed
Close
, and
AD Bocking
Search for other papers by AD Bocking in
Current site
Google Scholar
PubMed
Close
Free access

Sign up for journal news

The present study examines the effect of carotid sinus/vagosympathetic denervation on fetal endocrine responses to prolonged reduced uterine blood flow (RUBF). Fetal sheep had vascular catheters inserted following bilateral sectioning of the carotid sinus and vagus nerves (denervated, n = 7) or sham denervation (intact, n = 7). Uterine blood flow was mechanically restricted at 126.1 +/- 0.7 days (mean +/- S.E.M.) for 24 h, decreasing arterial oxygen saturation by 47.3 +/- 2.6% (P < 0.01). Fetal plasma samples were obtained at -1, 3, 6, 12 and 24 h for subsequent analyses of arginine vasopressin (AVP), angiotensin II and catecholamines. The AVP response to prolonged RUBF was markedly attenuated in denervated fetuses (15.6 +/- 3.6 to 34.9 +/- 6.0 pg/ml) when compared with intact (10.0 +/- 1.4 to 127.3 +/- 28.4 pg/ml). In contrast, intact fetuses demonstrated no change in plasma angiotensin II concentrations with RUBF whereas denervated fetuses demonstrated a marked increase from 47.5 +/- 18.9 to 128.7 +/- 34.2 pg/ml. The norepinephrine and epinephrine responses to prolonged RUBF were attenuated in denervated fetuses (950.1 +/- 308.9 and 155.8 +/- 58.5 to 1268.3 +/- 474.6 and 290.6 +/- 160.2 pg/ml respectively) when compared with intact (1558.3 +/- 384.4 and 547.3 +/- 304.7 pg/ml to 3289.2 +/- 1219.8 and 896.8 +/- 467.8 pg/ml respectively). These results support a role for the peripheral chemoreceptors in mediating fetal endocrine responses to prolonged RUBF, which may in part lead to the altered cardiovascular responses observed in denervated fetuses under these conditions.

 

  • Collapse
  • Expand