Oxytocin does not directly affect vascular tone in vessels from nonpregnant and pregnant rats
| Autor: | Sandra T. Davidge, B. F. Mitchell, M. E. Miller |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
medicine.medical_specialty
Vascular smooth muscle Physiology Vasodilation Oxytocin Muscle Smooth Vascular Rats Sprague-Dawley Phenylephrine Pregnancy Physiology (medical) Internal medicine medicine Animals Aorta Abdominal Methacholine Chloride Reverse Transcriptase Polymerase Chain Reaction business.industry Uterus Arteries Oxytocin receptor Mesenteric Arteries Rats medicine.anatomical_structure Endocrinology Gene Expression Regulation Great vessels Receptors Oxytocin Vasoconstriction Muscle Tonus Circulatory system Vascular resistance Pregnancy Animal Female Cardiology and Cardiovascular Medicine business Blood vessel medicine.drug |
| Zdroj: | American Journal of Physiology-Heart and Circulatory Physiology. 282:H1223-H1228 |
| ISSN: | 1522-1539 0363-6135 |
| DOI: | 10.1152/ajpheart.00774.2001 |
| Popis: | Recent evidence suggests oxytocin (OT) may regulate vascular tone. OT and its receptor (OTR) have been identified in the rat heart and great vessels. Expression of OT and OTR is increased in some tissues during pregnancy. We hypothesized that the OT/OTR system may be a physiological regulator of vascular tone and mediate the decreased vascular resistance noted during pregnancy. Using a wire myograph system, we measured changes in vascular tone in response to OT in small mesenteric arteries, uterine arcuate arteries, and thoracic aorta from nonpregnant and pregnant rats. Additionally, we used reverse transcriptase-polymerase chain reaction (RT-PCR) to measure mRNA for OTR in these vascular tissues. Although OTR mRNA was identified by RT-PCR, OT did not elicit a vasodilatory effect in any of the vessels studied. High concentrations of OT (>10−8 M) caused vasoconstriction that was eliminated by a specific vasopressin V1a receptor antagonist. Although it may have an indirect effect in regulation of peripheral resistance, we conclude that OT is unlikely to play a direct role in the physiological regulation of vascular tone. |
| Databáze: | OpenAIRE |
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