Systemic hemodynamics and oxygen transport during pregnancy in chronically instrumented, conscious rats

1992 ◽  
Vol 263 (6) ◽  
pp. H1911-H1918 ◽  
Author(s):  
G. J. Gilson ◽  
M. D. Mosher ◽  
K. P. Conrad

Knowledge about possible alterations in cardiac output (CO), total peripheral vascular resistance (TPVR), and their time course and magnitude of change is conspicuously lacking for the conscious gravid rat. Therefore, we assessed CO using Fick methodology in unrestrained, chronically instrumented, conscious rats. The rats were studied during early (day 7), mid (day 13), or late gestation (day 18) along with nonpregnant control rats matched with respect to age and days postsurgery. Significant differences between pregnant and nonpregnant rats were observed during midgestation, when CO was increased by 26 +/- 12% and TPVR was decreased by 23 +/- 9% in the pregnant animals. These changes were accompanied by a narrowed arterial-mixed venous oxygen content difference (AVD; P < 0.05 vs. nonpregnant). In late gravid rats, CO was higher than nonpregnant values by 49 +/- 8%, and TPVR was lower by 34 +/- 7% (both P < 0.05). Oxygen consumption and carbon dioxide production were significantly increased, and AVD further narrowed when compared with the nonpregnant control group. With the exception of absent chronic respiratory alkalosis in pregnant rats, we conclude that cardiovascular and respiratory changes in conscious, gravid rats and in pregnant women are comparable. We speculate that the ultimate purpose of many of these adaptations is to increase CO so that oxygen delivery and the supply of nutrients to the uteroplacental units are sufficient or more than sufficient to meet oxygen and nutrient demands. At midgestation, the rise in CO seems to anticipate the oxygen needs of the nascent uteroplacental units.

2012 ◽  
Vol 24 (5) ◽  
pp. 704 ◽  
Author(s):  
Constanza M. López-Fontana ◽  
María E. Maselli ◽  
Ana M. Salicioni ◽  
Rubén W. Carón

Lactogenesis is a very complex process highly dependent on hormonal regulation. In the present study the time-course of the inhibitory actions of progesterone on prolactin secretion, mammary gland morphology and lactogenesis from mid- to late gestation in rodents was investigated. Groups of pregnant rats were luteectomised or administered with mifepristone on Day 10, 13, 15 or 17 of gestation and decapitated 28 or 48 h later. Whole-blood samples and the inguinal mammary glands were taken for determinations of hormone levels and for measurement of mammary content of casein and lactose and for tissue morphology analyses, respectively. Luteectomy or mifepristone evoked prolactin increases only after Day 17 of gestation. Mammary content of casein was increased by both treatments regardless of timing or duration. Mifepristone was less effective than luteectomy in inducing lactose production and the effect was only observed after Day 15 of gestation. Analysis of mammary gland morphology confirmed the observed effect of progesterone on lactogenesis. Both treatments triggered remarkable secretory activity in the mammary gland, even without a parallel epithelial proliferation, demonstrating that the mammary epithelium is able to synthesise milk compounds long before its full lobulo–alveolar development is achieved, provided that progesterone action is abolished. Thus, the present study demonstrates that progesterone is a potent hormonal switch for the prolactin and prolactin-like effects on mammary gland development and its milk-synthesising capacity during pregnancy, and that its inhibitory action is already evident by mid-pregnancy in rodents.


2021 ◽  
Author(s):  
Przemysław Adamczyk ◽  
Martin Jáni ◽  
Tomasz S. Ligeza ◽  
Olga Płonka ◽  
Piotr Błądziński ◽  
...  

AbstractFigurative language processing (e.g. metaphors) is commonly impaired in schizophrenia. In the present study, we investigated the neural activity and propagation of information within neural circuits related to the figurative speech, as a neural substrate of impaired conventional metaphor processing in schizophrenia. The study included 30 schizophrenia outpatients and 30 healthy controls, all of whom were assessed with a functional Magnetic Resonance Imaging (fMRI) and electroencephalography (EEG) punchline-based metaphor comprehension task including literal (neutral), figurative (metaphorical) and nonsense (absurd) endings. The blood oxygenation level-dependent signal was recorded with 3T MRI scanner and direction and strength of cortical information flow in the time course of task processing was estimated with a 64-channel EEG input for directed transfer function. The presented results revealed that the behavioral manifestation of impaired figurative language in schizophrenia is related to the hypofunction in the bilateral fronto-temporo-parietal brain regions (fMRI) and various differences in effective connectivity in the fronto-temporo-parietal circuit (EEG). Schizophrenia outpatients showed an abnormal pattern of connectivity during metaphor processing which was related to bilateral (but more pronounced at the left hemisphere) hypoactivation of the brain. Moreover, we found reversed lateralization patterns, i.e. a rightward-shifted pattern during metaphor processing in schizophrenia compared to the control group. In conclusion, the presented findings revealed that the impairment of the conventional metaphor processing in schizophrenia is related to the bilateral brain hypofunction, which supports the evidence on reversed lateralization of the language neural network and the existence of compensatory recruitment of alternative neural circuits in schizophrenia.


2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 7-7
Author(s):  
Betty R McConn ◽  
Alan W Duttlinger ◽  
Kouassi R Kpodo ◽  
Jacob M Maskal ◽  
Brianna N Gaskill ◽  
...  

Abstract Pregnant sows, especially during late-gestation, may be susceptible to heat stress due to increased metabolic heat production and body mass. Therefore, the study objective was to determine the thermoregulatory and physiological responses of sows exposed to increasing ambient temperature (TA) at 3 reproductive stages. In 3 repetitions, 27 multiparous sows (parity 3.22±0.89) were individually housed and had jugular catheters placed 5.0±1.0 d prior to the experiment. To differentiate between reproductive stages, sows were categorized as open (not pregnant, n=9), mid-gestation (59.7±9.6 days pregnant, n=9), or late-gestation (99.0±4.8 days pregnant, n=9). During the experiment, sows were exposed to 6 consecutive 1 h periods of increasing TA (period 1, 14.39±2.14°C; period 2, 16.20±1.39°C; period 3, 22.09±1.87°C; period 4, 26.34±1.39°C; period 5, 30.56±0.81°C; period 6, 35.07±0.96°C), with 1 h transition phases in between each period. Respiration rate (RR), heart rate (HR), skin temperature, and vaginal temperature (TV) were measured every 20 min and the mean was calculated for each period. At the end of each period, blood gases, leukocytes, and red blood cell counts were measured. Overall, RR and HR were greater (P≤0.04; 45.6% and 12.9%, respectively) in late-gestation versus mid-gestation sows. Compared to mid-gestation and open sows, TV tended to be greater (P=0.06) during period 4 (0.18°C and 0.29°C, respectively) and period 5 (0.14°C and 0.18°C, respectively) in late-gestation sows. Blood O2 increased (P&lt; 0.01; 18.1%) for all sows with advancing period, regardless of reproductive stage. Late-gestation sows had reduced (P=0.02; 16.1%) blood CO2 compared to mid-gestation sows, regardless of period. In summary, late-gestation sows appear to be more sensitive to increasing TA as indicated by increased RR, HR, TV, and blood O2, and reduced blood CO2 when compared to mid-gestation or open sows. This change in O2 and CO2, due to increasing RR and heat stress sensitivity of late-gestation sows, may suggest an alteration to the acid-base balance, leading to respiratory alkalosis.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Patricia Pleguezuelos ◽  
Marina Sibila ◽  
Raúl Cuadrado ◽  
Rosa López-Jiménez ◽  
Diego Pérez ◽  
...  

Abstract Background The objective of the present study was to explore the benefits of Porcine circovirus 2 (PCV-2) blanket vaccination in a sow herd on productive parameters, PCV-2 infection and immune status in sows and their progeny. For this purpose, 288 sows were distributed among four balanced experimental groups. One group remained as negative control group and the other three received 1 mL of PCV-2 Ingelvac Circoflex® intramuscularly at different productive cycle moments: before mating, mid gestation (42–49 days post-insemination) or late gestation (86–93 days post-insemination); phosphate buffered saline (PBS) was used as negative control item. Reproductive parameters from sows during gestation and body weight of their progeny from birth to weaning were recorded. Additionally, blood was collected from sows at each vaccination time and piglets at 3 weeks of age. Moreover, up to 4 placental umbilical cords (PUC) per sow were taken at peri-partum. Sera from sows and piglets were analysed for PCV-2 antibody detection using an enzyme-linked immunosorbent assay (ELISA). Sera from sows and PUC were tested to quantify viraemia using a real time quantitative polymerase chain reaction (qPCR) assay. Results Globally, results indicated that vaccinated sows showed heavier piglets at birth and at weaning, less cross-fostered piglets, lower viral load at farrowing as well as in PUC, and higher antibody levels at farrowing, compared to non-vaccinated ones. When all groups were compared among them, sows vaccinated at mid or late gestation had heavier piglets at birth than non-vaccinated sows, and lower proportion of PCV-2 positive PUC. Also, cross-fostering was less frequently practiced in sows vaccinated at pre-mating or mid gestation compared to non-vaccinated ones. Conclusions In conclusion, the present study points out that PCV-2 sow vaccination at different time points of their physiological status (mimicking blanket vaccination) offers benefits at production and serological and virological levels.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
K Stamatelopoulos ◽  
D Delialis ◽  
D Bampatsias ◽  
M.E Tselegkidi ◽  
I Petropoulos ◽  
...  

Abstract Background The sporadic form of transthyretin amyloidosis cardiomyopathy (ATTR-CM) is underdiagnosed but its prevalence is increasing due to the aging population. Given the poor prognosis of ATTR-CM understanding the underlying pathophysiologic mechanisms of the disease is imperative in order to improve strategies for early diagnosis and risk stratification and to develop new effective therapeutic options. ATTR-CM is associated with hypotension and there is preliminary experimental evidence of vascular involvement but its presence and clinical significance remains unknown. Purpose To characterize peripheral arterial involvement and explore its clinical role in ATTR-CM. Methods We consecutively recruited 28 previously untreated patients with newly diagnosed ATTR-CM and 34 elderly controls &gt;70 years old, without ATTR-CM or heart failure. In both groups, flow-mediated dilatation (FMD) and intima-media thickness (IMT) in the carotid arteries were measured by high-resolution ultrasonography as markers of peripheral vascular reactivity and of subclinical atherosclerosis, respectively. Carotid-femoral pulse wave velocity (PWV) was measured as a marker of arterial stiffness. Aortic blood pressure (BP) and augmentation index (AI) using applanation tonometry were measured as markers of arterial wave reflections, peripheral arterial resistance and central hemodynamics. Echocardiography was performed in all ATTR patients. All cardiovascular (CV) measurements were performed before administration of any ATTR-specific therapy. Results ATTR patients were older and had lower prevalence of hypertension and male gender (p&lt;0.05 for all) than the control group. Aortic and peripheral BP (p=0.016–0.088) and AI (p=0.003) were lower in ATTR patients. IMT in the common (cc) and internal carotid (ic) as well as in the carotid bulb (cb) were significantly higher in ATTR patients (p=0.001–0.042). After multivariable adjustment for traditional CV disease (CVD) risk factors, the ATTR group was independently associated with AI and IMT in cc, cb and ic (p&lt;0.05 for all). In a subgroup of subjects with similar age between groups (n=13 and n=33 and 74.5±2.9 vs. 75.6±3.6 years, for ATTR vs. controls, respectively) differences in AI and cbIMT remained significant. Interestingly, AI was strongly and inversely associated with interventricular wall thickness (IVwt) in ATTR patients (spearman rho=−0.651, p=0.001). After adjustment for traditional CVD risk factors this association remained significant. Conclusion ATTR-CM is associated with lower aortic wave reflections, which correlate with more advanced structural cardiac disease, as assessed by IVwt. Further, ATTR-CM patients present accelerated subclinical carotid atherosclerosis as compared to elderly control subjects. These findings suggest that in ATTR-CM there is disease-specific peripheral vascular involvement in parallel to cardiac involvement. The clinical significance of these findings merits further investigation. Funding Acknowledgement Type of funding source: None


2021 ◽  
Vol 10 (8) ◽  
pp. 1786
Author(s):  
Valeria Pergola ◽  
Marco Previtero ◽  
Annagrazia Cecere ◽  
Vittorio Storer ◽  
Teresa Castiello ◽  
...  

The introduction of high-sensitivity cardiac troponin allowed identifying a proportion of subjects with chest pain and electrocardiographic changes suggestive of myocardial infarction showing <50% coronary artery stenosis. PFAI is a coronary CT marker proved to predict outcome in ischemic heart disease. Based on CMR findings, patients were divided into myocarditis (n = 15), MINOCA (n = 14) and TTS (n = 9) groups. The aim was to estimate the value of pFAI in these groups compared to 12 controls. To evaluate the coronary inflammation “time course,” 20 patients underwent CMR and coronary CT scan within 8 days from the onset, the others within 60 days. There were higher values of pFAI in myocarditis (−86.45 HU), MINOCA (−84.63 HU) and TTS (−84.79 HU) compared to controls (−96.02 HU; p = 0.0077). Among patients who underwent CT within 8 days from onset, the MINOCA had a significantly higher pFAI value (−76.91 HU) compared to the control group (−96.02 HU; p = 0.0001). In the group that underwent CT later than 8 days, elevated pFAI values persisted only in the myocarditis and TTS groups, and there was no difference between MINOCA and controls. Our study shows that in patients with a diagnosis of MINOCA, there is acute coronary inflammation, which is more evident within one week from the acute event but tends to disappear with time.


2016 ◽  
Vol 2016 ◽  
pp. 1-8
Author(s):  
Qianli Tang ◽  
Qiuyan Jiang ◽  
Suren R. Sooranna ◽  
Shike Lin ◽  
Yuanyuan Feng ◽  
...  

To observe the effects of electroacupuncture on pain threshold of laboring rats and the expression of norepinephrine transporter andα2 adrenergic receptor in the central nervous system to determine the mechanism of the analgesic effect of labor. 120 pregnant rats were divided into 6 groups: a control group, 4 electroacupuncture groups, and a meperidine group. After interventions, the warm water tail-flick test was used to observe pain threshold. NE levels in serum, NET, andα2AR mRNA and protein expression levels in the central nervous system were measured. No difference in pain threshold was observed between the 6 groups before intervention. After intervention, increased pain thresholds were observed in all groups except the control group with a higher threshold seen in the electroacupuncture groups. Serum NE levels decreased in the electroacupuncture and MP groups. Increases in NET andα2AR expression in the cerebral cortex and decreases in enlarged segments of the spinal cord were seen. Acupuncture increases uptake of NE via cerebral NET and decreases its uptake by spinal NET. The levels ofα2AR are also increased and decreased, respectively, in both tissues. This results in a decrease in systemic NE levels and may be the mechanism for its analgesic effects.


2009 ◽  
Vol 117 (3) ◽  
pp. 129-138 ◽  
Author(s):  
Emily M. Segar ◽  
Andrew W. Norris ◽  
Jian-Rong Yao ◽  
Shanming Hu ◽  
Stacia L. Koppenhafer ◽  
...  

ODM (offspring of diabetic mothers) have an increased risk of developing metabolic and cardiovascular dysfunction; however, few studies have focused on the susceptibility to disease in offspring of mothers developing diabetes during pregnancy. We developed an animal model of late gestation diabetic pregnancy and characterized metabolic and vascular function in the offspring. Diabetes was induced by streptozotocin (50 mg/kg of body weight, intraperitoneally) in pregnant rats on gestational day 13 and was partially controlled by twice-daily injections of insulin. At 2 months of age, ODM had slightly better glucose tolerance than controls (P<0.05); however, by 6 months of age this trend had reversed. A euglycaemic–hyperinsulinamic clamp revealed insulin resistance in male ODM (P<0.05). In 6–8-month-old female ODM, aortas had significantly enhanced contractility in response to KCl, ET-1 (endothelin-1) and NA (noradrenaline). No differences in responses to ET-1 and NA were apparent with co-administration of L-NNA (NG-nitro-L-arginine). Relaxation in response to ACh (acetylcholine), but not SNP (sodium nitroprusside), was significantly impaired in female ODM. In contrast, males had no between-group differences in response to vasoconstrictors, whereas relaxation to SNP and ACh was greater in ODM compared with control animals. Thus the development of diabetes during pregnancy programmes gender-specific insulin resistance and vascular dysfunction in adult offspring.


Author(s):  
Juan A. Barios ◽  
Santiago Ezquerro ◽  
Arturo Bertomeu-Motos ◽  
Jose M. Catalan ◽  
Jose M. Sanchez-Aparicio ◽  
...  

Conventional rehabilitation strategies for stroke survivors become difficult when voluntary movements are severely disturbed. Combining passive limb mobilization, robotic devices and EEG-based brain-computer interfaces (BCI) systems might improve treatment and clinical follow-up of these patients, but detailed knowledge of neurophysiological mechanisms involved in functional recovery, which might help for tailoring stroke treatment strategies, is lacking. Movement-related EEG changes (EEG event-related desynchronization (ERD) in [Formula: see text] and [Formula: see text] bands, an indicator of motor cortex activation traditionally used for BCI systems), were evaluated in a group of 23 paralyzed chronic stroke patients in two unilateral motor tasks alternating paretic and healthy hands ((i) passive movement, using a hand exoskeleton, and (ii) voluntary movement), and compared to nine healthy subjects. In tasks using unaffected hand, we observed an increase of contralesional hemisphere activation for stroke patients group. Unexpectedly, when using paralyzed hand, motor cortex activation was reduced or absent in severely affected group of patients, while patients with moderate motor deficit showed an activation greater than control group. Cortical activation was reduced or absent in damaged hemisphere of all the patients in both tasks. Significant differences related to severity of motor deficit were found in the time course of [Formula: see text] bands power ratio in EEG of contralesional hemisphere while moving affected hand. These findings suggest the presence of different compensation mechanisms in contralesional hemisphere of stroke patients related to the grade of motor disability, that might turn quantitative EEG during a movement task, obtained from a BCI system controlling a robotic device included in a rehabilitation task, into a valuable tool for monitoring clinical progression, evaluating recovery, and tailoring treatment of stroke patients.


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