scholarly journals Intrauterine infusion of killed semen adversely affects uterine blood flow and endometrial gene expression of inflammatory cytokines in mares susceptible to persistent breeding-induced endometritis

2021 ◽  
Vol 163 ◽  
pp. 18-30
Author(s):  
J. Lüttgenau ◽  
I. Imboden ◽  
O. Wellnitz ◽  
R. Romer ◽  
I. Scaravaggi ◽  
...  
Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Jennifer N Koch ◽  
Elizabeth A Owens ◽  
Shelby Dahlen ◽  
Jie Li ◽  
Patrick Osei Owusu

Regulators of G protein signaling (RGS) proteins are crucial in mediating vascular smooth muscle contraction via the regulation of heterotrimeric G proteins, affecting blood pressure and arterial blood flow. Previous studies by others and us showed that RGS2 deficiency augments vascular tone and impairs uterine blood flow (UBF) in non-pregnant mice, and that an Rgs2 loss-of-function mutation is linked to preeclampsia in humans; however, the mechanisms are unclear. Here, we tested the hypothesis that increased RGS2 expression and/or function facilitates placental perfusion by promoting vasodilation and UBF. We determined gene expression throughout pregnancy and post-partum period by real-time qPCR, while uterine blood flow and blood pressure were examined by ultrasound and carotid artery catheterization, respectively, under anesthesia. RGS2 expression decreased markedly by pregnancy day 10 (0.049 ± 0.013 vs. 0.023 ± 0.017) but returned to non-pregnancy level by day 15 (0.049 ± 0.013 vs. 0.041 ± 0.008,) in wild type mice. The pattern of changes in impedance to UBF mimicked gene expression profile in WT mice; in contrast, impedance remained elevated in Rgs2-/- mice at pregnancy day 15 (RI; WT: 0.516 ± 0.027, vs. RGS2-/-: 0.714 ± 0.020). Systemic blood pressure was similar between WT and Rgst2-/- mice at all stages of pregnancy. The results together indicate that RGS2 promotes uterine perfusion during pregnancy independently of its blood pressure effects. These findings are clinically relevant as selective targeting of G protein signaling could improve utero-placental hypoperfusion during pregnancy and prevent the development of pregnancy complications such as preeclampsia.


Ob Gyn News ◽  
2007 ◽  
Vol 42 (13) ◽  
pp. 23
Author(s):  
Kate Johnson

1988 ◽  
Vol 65 (6) ◽  
pp. 2420-2426 ◽  
Author(s):  
A. D. Bocking ◽  
R. Gagnon ◽  
K. M. Milne ◽  
S. E. White

Experiments were conducted in unanesthetized, chronically catheterized pregnant sheep to determine the fetal behavioral response to prolonged hypoxemia produced by restricting uterine blood flow. Uterine blood flow was reduced by adjusting a vascular occluder placed around the maternal common internal iliac artery to decrease fetal arterial O2 content from 6.1 +/- 0.3 to 4.1 +/- 0.3 ml/dl for 48 h. Associated with the decrease in fetal O2 content, there was a slight increase in fetal arterial PCO2 and decrease in pH, which were both transient. There was an initial inhibition of both fetal breathing movements and eye movements but no change in the pattern of electrocortical activity. After this initial inhibition there was a return to normal incidence of both fetal breathing movements and eye movements by 16 h of the prolonged hypoxemia. These studies indicate that the chronically catheterized sheep fetus is able to adapt behaviorally to a prolonged decrease in arterial O2 content secondary to the restriction of uterine blood flow.


2013 ◽  
Vol 118 (4) ◽  
pp. 796-808 ◽  
Author(s):  
Pornswan Ngamprasertwong ◽  
Erik C. Michelfelder ◽  
Shahriar Arbabi ◽  
Yun Suk Choi ◽  
Christopher Statile ◽  
...  

Abstract Background: Use of high-dose inhalational anesthesia during open fetal surgery may induce maternal–fetal hemodynamic instability and fetal myocardial depression. The authors’ preliminary human retrospective study demonstrated less fetal bradycardia and left ventricular systolic dysfunction with lower dose desflurane supplemented with propofol and remifentanil IV anesthesia (SIVA). In this animal study, the authors compare maternal–fetal effects of high-dose desflurane anesthesia (HD-DES) and SIVA. Methods: Of 26 instrumented midgestational ewes, data from 11 animals exposed to both SIVA and HD-DES in random sequences and six animals exposed to HD-DES while maternal normotension was maintained were analyzed. Maternal electroencephalography was used to guide comparable depths of anesthesia in both techniques. Hemodynamic parameters, blood gas, and fetal cardiac function from echocardiography were recorded. Results: Compared with SIVA, HD-DES resulted in significant maternal hypotension (mean arterial pressure difference, 19.53 mmHg; 95% CI, 17.6–21.4; P < 0.0001), fetal acidosis (pH 7.11 vs. 7.24 at 150 min, P < 0.001), and decreased uterine blood flow. In the HD-DES group with maternal normotension, uterine blood flow still declined and fetal acidosis persisted, with no statistically significant difference from the group exposed to HD-DES that had maternal hypotension. There was no statistically significant difference in fetal cardiac function. Conclusion: In sheep, SIVA affects maternal hemodynamics less and provides better fetal acid/base status than high-dose desflurane. Fetal echocardiography did not reflect myocardial dysfunction in this model.


1982 ◽  
Vol 242 (3) ◽  
pp. H429-H436 ◽  
Author(s):  
R. B. Wilkening ◽  
S. Anderson ◽  
L. Martensson ◽  
G. Meschia

The effect of variations of uterine blood flow (F) on placental transfer was examined in six chronic sheep preparations by measuring the placental clearances of ethanol (CE) and antipyrine (CA) at different levels of F. Norepinephrine infusion, hemorrhage, and occlusion of the terminal aorta were used to reduce F below normal. The reduction of F had no appreciable effect on umbilical blood flow (f). In each ewe, CE significantly correlated with F. The CE vs. F relationship at constant f was curvilinear with convexity toward the clearance axis. Regression analysis showed that the equation 1/CE = 1/.911 F + 1/.831 f could account for most of the CE variance (r2 = 0.97). Implicit in this relation is the concept that, given a certain level of placental perfusion, an F/f ratio congruent to 1 is optimal for the exchange of highly diffusible inert molecules between mother and fetus [CE/(F + f) was maximum at F/f = 0.955]. CA was not significantly different from CE at low clearance level but became smaller than CE at clearance values greater than 300 ml/min. This suggests that a high rates of perfusion placental permeability was a factor in limiting CA.


2008 ◽  
Vol 5 (2) ◽  
pp. 145-151 ◽  
Author(s):  
Sae Uchida ◽  
Harumi Hotta

In this review, our recent studies using anesthetized animals concerning the neural mechanisms of vasodilative effect of acupuncture-like stimulation in various organs are briefly summarized. Responses of cortical cerebral blood flow and uterine blood flow are characterized as non-segmental and segmental reflexes. Among acupuncture-like stimuli delivered to five different segmental areas of the body; afferent inputs to the brain stem (face) and to the spinal cord at the cervical (forepaw), thoracic (chest or abdomen), lumbar (hindpaw) and sacral (perineum) levels, cortical cerebral blood flow was increased by stimuli to face, forepaw and hindpaw. The afferent pathway of the responses is composed of somatic groups III and IV afferent nerves and whose efferent nerve pathway includes intrinsic cholinergic vasodilators originating in the basal forebrain. Uterine blood flow was increased by cutaneous stimulation of the hindpaw and perineal area, with perineal predominance. The afferent pathway of the response is composed of somatic group II, III and IV afferent nerves and the efferent nerve pathway includes the pelvic parasympathetic cholinergic vasodilator nerves. Furthermore, we briefly summarize vasodilative regulation of skeletal muscle blood flow via a calcitonin gene-related peptide (CGRP) induced by antidromic activation of group IV somatic afferent nerves. These findings in healthy but anesthetized animals may be applicable to understanding the neural mechanisms improving blood flow in various organs following clinical acupuncture.


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