| Title: |
The Characterization of Circular and Longitudinal Uterine Smooth Muscle Function from Non‐Pregnant and Late‐Pregnant Rats |
| Authors: |
Mejia, Raqueliz E; Leovic, Michael; Hoxha, Brikena; Ion, Elena; Vallejo‐Elias, Johana; Jones, Carleton “Buck”; Struthers, Jason; Eckman, Delrae M. |
| Source: |
The FASEB Journal ; volume 33, issue S1 ; ISSN 0892-6638 1530-6860 |
| Publisher Information: |
Wiley |
| Publication Year: |
2019 |
| Collection: |
Wiley Online Library (Open Access Articles via Crossref) |
| Description: |
Objective/Introduction The rodent uterus is a hollow organ that increases approximately 10 fold in size with pregnancy. Myometrial smooth muscle orients longitudinally and circularly allowing flexibility in size and shape during pregnancy. To date most studies have focused on changes in longitudinal smooth muscle with pregnancy. Here we studied how circular smooth muscle of the uterus changes with pregnancy in comparison with longitudinal muscle. Methods Studies were performed in age‐matched (~77days) non‐pregnant (NP, n=5) and late‐pregnant (LP, d21g±1d, n=4) Sprague‐Dawley rats. Uterine horns from NP and LP rats were rapidly removed, placed in 4°C PSS, and cleaned of all connective tissue. Uterine tissue was cut (ovary to uterine body) allowing both longitudinal muscle (LM) and circular muscle (CM) strips (width: 1.5mm, length: ~4mmt) to be isolated. Muscle strips were mounted in vertical organ chamber baths containing PSS and maintained @ 37°C. After ~45 min. equilibration, strips were challenged with 60mM [K + ] o . Tissues not responding to 60mM [K + ] o were excluded. Strips were assessed using one of two protocols. Protocol 1: Optimal stretch (L 0 ) ‐ determined by comparing spontaneous contractile activity (e.g., contraction amplitude, area under the curve (AUC), and frequency), along with 60mM [K + ] o ‐induced contraction (contraction amplitude and AUC) at 250mg, 500mg, and 1000mg resting tension. Protocol 2: Passive mechanical characteristics ‐ Stress vs strain (SvS) relationships were assessed in CM and LM strips. Tissue equilibrated in Ca 2+ free PSS to eliminate spontaneous contractility. Tissue was then stretched in 500 μm steps until tissue failure. Results Our data indicates pregnancy significantly increases K + ‐induced constriction amplitude, and K + ‐induced AUC of CM (P |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1096/fasebj.2019.33.1_supplement.lb655 |
| Availability: |
http://dx.doi.org/10.1096/fasebj.2019.33.1_supplement.lb655 |
| Rights: |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
| Accession Number: |
edsbas.C8DA01A6 |
| Database: |
BASE |