Role of impaired endothelial cell Ca(2+) signaling in uteroplacental vascular dysfunction during diabetic rat pregnancy

Diabetes mellitus in pregnancy is associated with impaired endothelium-mediated dilatation of maternal arteries, although the underlying cellular mechanisms remain unknown. In this study, we hypothesized that diabetes during rat gestation attenuates agonist-induced uterine vasodilation through reduced endothelial cell (EC) Ca(2+) elevations and impaired smooth muscle cell (SMC) hyperpolarization and SMC intracellular Ca(2+) concentration ([Ca(2+)]i) responses. Diabetes was induced by an injection of streptozotocin to second-day pregnant rats and confirmed by the development of maternal hyperglycemia. Control rats were injected with a citrate buffer. Fura-2-based measurements of SMC [Ca(2+)]i or microelectrode recordings of SMC membrane potential were performed concurrently with dilator responses to ACh in uteroplacental arteries from control and diabetic pregnant rats. Basal levels of EC [Ca(2+)]i and ACh-induced EC [Ca(2+)]i elevations in pressurized vessels and small EC sheets were studied as well. Diabetes reduced ACh-induced vasodilation due to a markedly impaired EDHF-mediated response. Diminished vasodilation to ACh was associated with attenuated SMC hyperpolarization and [Ca(2+)]i responses. Basal levels of EC [Ca(2+)]i and ACh-induced EC [Ca(2+)]i elevations were significantly reduced by diabetes. In conclusion, these data demonstrate that reduced endothelium-mediated hyperpolarization contributes to attenuated uteroplacental vasodilation and SMC [Ca(2+)]i responses to ACh in diabetic pregnancy. Impaired endothelial Ca(2+) signaling is in part responsible for endothelial dysfunction in the uterine resistance vasculature of diabetic rats. Pharmacological improvement of EC Ca(2+) handling may provide an important strategy for the restoration of endothelial function and enhancement of maternal blood flow in human pregnancies complicated by diabetes.

Medienart:

E-Artikel

Erscheinungsjahr:

2013

Erschienen:

2013

Enthalten in:

Zur Gesamtaufnahme - volume:304

Enthalten in:

American journal of physiology. Heart and circulatory physiology - 304(2013), 7 vom: 01. Apr., Seite H935-45

Sprache:

Englisch

Beteiligte Personen:

Gokina, Natalia I [VerfasserIn]
Bonev, Adrian D [VerfasserIn]
Gokin, Alexander P [VerfasserIn]
Goloman, Gabriela [VerfasserIn]

Links:

Volltext

Themen:

Acetylcholine
Biological Factors
Calcium
Endothelium-dependent hyperpolarization factor
Journal Article
N9YNS0M02X
Research Support, N.I.H., Extramural
SY7Q814VUP

Anmerkungen:

Date Completed 11.06.2013

Date Revised 21.10.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1152/ajpheart.00513.2012

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM224713140