Effects of prior adrenalectomy on postpneumonectomy lung growth in the rat

The effects of adrenalectomy, with and without subsequent glucocorticoid replacement therapy, on postpneumonectomy compensatory lung growth in the rat were investigated. Male Sprague-Dawley rats (200-230 g) were subjected to no operation (UNOP), left pneumonectomy (PNX), or PNX preceded by bilateral adrenalectomy 5 days earlier (ADX/PNX). At 14 days post-PNX, when compensatory lung growth is normally complete in 200-g rats, right lung (RL) dry weights of PNX (263 +/- 6 mg, n = 26) and ADX/PNX (334 +/- 13 mg, n = 25) rats were increased 58 and 101%, respectively, relative to UNOP controls (166 +/- 5 mg, n = 10). Increases in total DNA, RNA, and protein in the right lungs of PNX and ADX/PNX rats occurred in proportion to RL dry mass. The increase in all parameters examined in PNX and ADX/PNX rats at 7 days post-PNX was half that at 14 days, indicating linear lung growth in both treatment groups. The stimulatory effect of ADX on lung growth was blocked by hydrocortisone acetate (HCA), administered intraperitoneally in daily doses of 5 mg/kg, beginning on the day of PNX. The RL dry weights of HCA-treated ADX/PNX rats (241 +/- 7 mg, n = 10) did not differ significantly from the corresponding value in PNX rats (270 +/- 14 mg, n = 7). The lower RL weights in the HCA-treated rats resulted from an inhibition of cell division, as evidenced by the total RL DNA content, which was similar to that in PNX animals.(ABSTRACT TRUNCATED AT 250 WORDS)

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Control of compensatory lung growth by adrenal hormones

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1987.253.4.e343 ◽

1987 ◽

Vol 253 (4) ◽

pp. E343-E348 ◽

Cited By ~ 3

Author(s):

D. E. Rannels ◽

H. W. Karl ◽

R. A. Bennett

Keyword(s):

Dry Mass ◽

Lung Mass ◽

Lung Growth ◽

Unoperated Control ◽

Adrenal Hormones ◽

Compensatory Lung Growth ◽

The Right ◽

Rna And Dna ◽

Left Pneumonectomy

The effects of adrenalectomy and/or in vivo treatment with hydrocortisone acetate (HCA;5 mg X kg-1 X day-1) on lung growth were investigated in control and pneumonectomized rats of 250 g body wt. Left pneumonectomy (day 0) initiated rapid hyperplastic growth of the right lung, which was unaffected by HCA. Similarly, HCA had no effect on lung growth in unoperated control animals. Two weeks after pneumonectomy, right lung dry mass, protein, RNA, and DNA were equal to that in both lungs of unoperated rats. Adrenalectomy 5 days before (day -5) left pneumonectomy increased the rate and extent of right lung growth, but did not change its hyperplastic character. Continuous HCA treatment (days -5 to 14) prevented the adrenalectomy-mediated increase in postpneumonectomy lung growth. "Early" HCA dosing (days -5 to 6) of adrenalectomized-pneumonectomized animals suppressed lung growth to the pneumonectomy level, but from days 7 to 14 growth accelerated to the adrenalectomized-pneumonectomized rate. Conversely, "late" HCA, initiated when adrenalectomized-pneumonectomized animals had restored normal total lung mass (days 6 to 14), quickly reduced right lung growth to rates typical of unoperated controls. The latter effects were not observed unless continuous steroid treatment was provided throughout this interval. The data support a role for glucocorticosteroids in modulation of the accelerated compensatory lung growth initiated by partial resection of the tissue.

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Effects of remote ischemic preconditioning on the deformability and aggregation of red blood cells in a rat endotoxemia model

Clinical Hemorheology and Microcirculation ◽

10.3233/ch-201084 ◽

2021 ◽

pp. 1-9

Author(s):

Yun-Hee Kim ◽

Sung-Uk Choi ◽

Jung-Min Youn ◽

Seung-Ha Cha ◽

Hyeon-Ju Shin ◽

...

Keyword(s):

Ischemic Preconditioning ◽

Remote Ischemic Preconditioning ◽

Sprague Dawley ◽

Aggregation Index ◽

Sprague Dawley Rats ◽

Endotoxemia Model ◽

Elongation Index ◽

The Right ◽

Phosphate Buffered Saline ◽

Severe Ischemia

BACKGROUND: The prevention of rheologic alterations in erythrocytes may be important for reducing sepsis-associated morbidity and mortality. Remote ischemic preconditioning (RIPC) has been shown to prevent tissue damage caused by severe ischemia and mortality resulting from sepsis. However, the effect of RIPC on erythrocytes in sepsis is yet to be determined. OBJECTIVE: To investigate the effect of RIPC on rheologic alterations in erythrocytes in sepsis. METHODS: Thirty male Sprague-Dawley rats were used in this study. An endotoxin-induced sepsis model was established by intraperitoneally injecting 20 mg/kg LPS (LPS group). RIPC was induced in the right hind limb using a tourniquet, with three 10-minute of ischemia and 10 min of reperfusion cycles immediately before the injection of LPS (RIPC/LPS group) or phosphate-buffered saline (RIPC group). The aggregation index (AI), time to half-maximal aggregation (T1/2), and maximal elongation index (EImax) of the erythrocytes were measured 8 h after injection. RESULTS: The AI, T1/2, and EImax values in the LPS and RIPC/LPS groups differed significantly from those in the RIPC group, but there were no differences between the values in the LPS and RIPC/LPS groups. CONCLUSIONS: RIPC did not prevent rheologic alterations in erythrocytes in the rat model of LPS-induced endotoxemia.

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Dexamethasone Suppressed LPS-Induced Matrix Metalloproteinase and Its Effect on Endothelial Glycocalyx Shedding

Mediators of Inflammation ◽

10.1155/2015/912726 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 25

Author(s):

Na Cui ◽

Hao Wang ◽

Yun Long ◽

Longxiang Su ◽

Dawei Liu

Keyword(s):

Escherichia Coli ◽

Vascular Endothelium ◽

Free Water ◽

Endothelial Glycocalyx ◽

Sprague Dawley ◽

Treatment Groups ◽

Protein Levels ◽

Sprague Dawley Rats ◽

The Matrix ◽

Rat Thoracic Aorta

The aim of this study is to determine the mechanism of sepsis-induced vascular hyperpermeability and the beneficial effect of glucocorticoid in protecting vascular endothelium. Male Sprague-Dawley rats were given either a bolus intraperitoneal injection of a nonlethal dose of LPS (Escherichia coli055:B5, 10 mg/kg, Sigma) or vehicle (pyrogen-free water). Animals of treatment groups were also given either dexamethasone (4 mg/kg, 30 min prior to LPS injection) or the matrix metalloproteinases (MMPs) inhibitor doxycycline (4 mg/kg, 30 min after LPS injection). Both activities and protein levels of MMP-2p<0.001and MMP-9p<0.001were significantly upregulated in aortic homogenates from LPS-treated rats, associated with decreased ZO-1p<0.001and syndecan-1p=0.011protein contents. Both dexamethasone and doxycycline could significantly inhibit MMPs activity and reserve the expressions of ZO-1 and syndecan-1. The inhibition of MMPs by dexamethasone was significantly lower than that by doxycycline, while the rescue of syndecan-1 expression from LPS-induced endotoxemic rat thoracic aorta was significantly higher in the dexamethasone-treated compared to the doxycycline-treatedp=0.03. In conclusion, activation of MMPs plays important role in regulating ZO-1 and syndecan-1 protein levels in LPS mediated endothelial perturbation. Both dexamethasone and doxycycline inhibit activation of MMPs that may contribute to the rescue of ZO-1 and syndecan-1 expression.

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Effects of Aqueous Quassia amara L. (Korales) Leaf Extract on the Cardiovascular and Respiratory Functions of Male Sprague-Dawley Rats

Acta Medica Philippina ◽

10.47895/amp.v52i6.280 ◽

2018 ◽

Vol 52 (6) ◽

Author(s):

Maria Concepcion C. Sison ◽

Lynn Crisanta R. Panganiban ◽

Daisy Mae A. Bagaoisan ◽

Nelia P. Cortes-Maramba

Keyword(s):

Blood Pressure ◽

Adult Male ◽

Leaf Extract ◽

Sprague Dawley ◽

Treatment Groups ◽

Respiratory Flow ◽

Sprague Dawley Rats ◽

Parallel Group ◽

Aqueous Leaf Extract ◽

Quassia Amara

Objective. To To evaluate potential effects of the aqueous extract of Quassia amara L. leaves on the cardiovascular and respiratory systems of adult male Sprague- Dawley rats. Methods. The cardiovascular and respiratory effects of the Quassia amara L. leaf extract on adult male SpragueDawley rats were assessed using non-invasive blood pressure (NIBP) determination and head-out plethysmography, respectively, in a randomized, parallel group study. Mean observations of blood pressure and heart rate were recorded at different time periods after dosing. Respiratory flow and irritation effects were evaluated using mean observations of respiratory rate (RR), tidal volume (TV), mid-expiratory flow rate (EF50), time of inspiration (TI) and expiration (TE), and time of break (TB) and pause (TP). Results. There were no significant differences among the control and the treatment groups in SBP, DBP and HR parameters. The extract showed statistically significant effect on mean RR by time period (F=2.45, p=0.0234), trends over time of TV among the dose groups (F=2.00, p=0.0202), and EF50 among dose groups ((F=3.11, p=0.0422). However, these did not correlate with the changes in the time of break (TB) and time of pause (TP) which are more sensitive and specific tests for respiratory irritation. Conclusion. Aqueous leaf extract of Quassia appeared to have no significant effects on SBP, DPB, Pulse pressure, and HR. There are no conclusive dose-related respiratory flow or pulmonary irritation effects.

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Cardiotoxic effects of pavetamine extracted from Pavetta harborii in the rat

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v75i3.100 ◽

2008 ◽

Vol 75 (3) ◽

Cited By ~ 7

Author(s):

L. Hay ◽

R.A. Schultz ◽

P.J. Schutte

Keyword(s):

Heart Failure ◽

Animal Model ◽

Carotid Artery ◽

Plant Material ◽

Active Component ◽

Systolic Function ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

The Right ◽

Induce Heart Failure

Previous studies have shown that crude extracts from Pavetta harborii as well as dried plant material have cardiotoxic effects on rats and sheep that can lead to heart failure. The active component has since been isolated and identified. This substance has been named pavetamine. The aim of this study was to determine whether pavetamine has cardiotoxic effects similar to those seen in previous reports, when administered to rats intraperitoneally. Sprague Dawley rats received two doses, initially 4 mg / kg and then 3 mg / kg pavetamine respectively and were monitored for 35 days before cardiodynamic parameters were measured by inserting a fluid-filled catheter into the left ventricle via the right carotid artery. These values were compared to those of control rats that had received only saline. Pavetamine significantly reduced systolic function and body mass in the treated rats, which indicates that it has the potential to induce heart failure in this animal model.

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Lung volumes after an increase in lung distension in pneumonectomized ferrets

Journal of Applied Physiology ◽

10.1152/jappl.1989.67.4.1418 ◽

1989 ◽

Vol 67 (4) ◽

pp. 1418-1421 ◽

Cited By ~ 14

Author(s):

J. T. McBride

Keyword(s):

Lung Resection ◽

Transpulmonary Pressure ◽

Tissue Growth ◽

Lung Growth ◽

Lung Volumes ◽

Compensatory Lung Growth ◽

Rubber Balloon ◽

Residual Capacity ◽

The Right

To investigate the role of lung distension in compensatory lung growth, the right lung of each of 21 adult male ferrets was replaced with a silicone rubber balloon filled with mineral oil. Three to thirteen weeks after surgery, the oil was removed through a subcutaneous port. Lung volumes were measured serially until 3–6 wk after balloon deflation. With pneumonectomy the total lung capacity (TLC) decreased to less than 50% of the preoperative value and remained essentially unchanged while the balloon was inflated. At balloon deflation, TLC and vital capacity did not change immediately, whereas functional residual capacity increased by 44%, indicating a change of 2–3 cmH2O in end-expiratory transpulmonary pressure. TLC increased by 10% within 3 days and continued to increase over the subsequent 3–5 wk by a total of 25% over TLC at balloon deflation. There was little difference in this response between animals whose balloons were deflated 3 wk after surgery and those in which deflation was delayed up to 13 wk. After pneumonectomy in the adult ferret, the remaining lung increases in volume in response to an increase in lung distension even weeks or months after surgery. The extent to which this volume increase involves lung tissue growth or depends on previous lung resection is at present unknown. This model may be useful for studies of the mechanisms by which lung distension influences lung volume and compensatory lung growth.

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Aversion to Desflurane and Isoflurane in Sprague-Dawley Rats (Rattus norvegicus)

Animals ◽

10.3390/ani10060950 ◽

2020 ◽

Vol 10 (6) ◽

pp. 950 ◽

Cited By ~ 1

Author(s):

Katrina Frost ◽

Maaria Shah ◽

Vivian S.Y. Leung ◽

Daniel S.J. Pang

Keyword(s):

Carbon Dioxide ◽

Exposure Time ◽

Washout Period ◽

Rattus Norvegicus ◽

Sprague Dawley ◽

Initial Exposure ◽

Treatment Groups ◽

Avoidance Paradigm ◽

Sprague Dawley Rats

Carbon dioxide and isoflurane are widely used for killing rats, yet may not truly achieve “euthanasia”, because they elicit aversion. The inhalant anesthetic desflurane is faster acting than isoflurane, representing a potential refinement. Using an aversion-avoidance paradigm, 24 rats were exposed to isoflurane or desflurane (n = 12 per group) at initial exposure. Fourteen rats were then re-exposed to isoflurane or desflurane (n = 7 per group), after a 7 days washout period. Initial exposure: time to recumbency was faster for desflurane than isoflurane (p = 0.0008, 95% CI [-12.9 to 32.6 s]), with 9/12 and 6/12 rats becoming recumbent, respectively. At initial exposure, there was no difference between groups in time to withdrawal (p = 0.714). At re-exposure, all rats withdrew and no rats became recumbent. Time to withdrawal at re-exposure did not differ between treatment groups (p = 0.083). Compared to initial exposure, time to withdrawal during re-exposure was similar for isoflurane (p = 0.228) and faster with desflurane (p = 0.012, 95% CI [19.1 to 49.5 s]). Isoflurane and desflurane are similarly aversive, with aversion increasing at re-exposure. The shorter time from exposure to recumbency with desflurane indicates that any distress is of a shorter duration when compared with isoflurane.

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Nitric oxide modulation of glutamatergic, baroreflex, and cardiopulmonary transmission in the nucleus of the solitary tract

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01149.2003 ◽

2005 ◽

Vol 288 (1) ◽

pp. H256-H262 ◽

Cited By ~ 40

Author(s):

Ana Carolina Rodrigues Dias ◽

Melissa Vitela ◽

Eduardo Colombari ◽

Steven W. Mifflin

Keyword(s):

Nitric Oxide ◽

Solitary Tract ◽

Glutamatergic Transmission ◽

Sprague Dawley ◽

Renal Sympathetic Nerve Activity ◽

Sprague Dawley Rats ◽

Before And After ◽

Nos Inhibitor ◽

The Right ◽

Oxide Synthase

The neuromodulatory effect of NO on glutamatergic transmission has been studied in several brain areas. Our previous single-cell studies suggested that NO facilitates glutamatergic transmission in the nucleus of the solitary tract (NTS). In this study, we examined the effect of the nitric oxide synthase (NOS) inhibitor NG-nitro-l-arginine methyl ester (l-NAME) on glutamatergic and reflex transmission in the NTS. We measured mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA) from Inactin-anesthetized Sprague-Dawley rats. Bilateral microinjections of l-NAME (10 nmol/100 nl) into the NTS did not cause significant changes in basal MAP, HR, or RSNA. Unilateral microinjection of ( RS)-α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA, 1 pmol/100 nl) into the NTS decreased MAP and RSNA. Fifteen minutes after l-NAME microinjections, AMPA-evoked cardiovascular changes were significantly reduced. N-methyl-d-aspartate (NMDA, 0.5 pmol/100 nl) microinjection into the NTS decreased MAP, HR, and RSNA. NMDA-evoked falls in MAP, HR, and RSNA were significantly reduced 30 min after l-NAME. To examine baroreceptor and cardiopulmonary reflex function, l-NAME was microinjected at multiple sites within the rostro-caudal extent of the NTS. Baroreflex function was tested with phenylephrine (PE, 25 μg iv) before and after l-NAME. Five minutes after l-NAME the decrease in RSNA caused by PE was significantly reduced. To examine cardiopulmonary reflex function, phenylbiguanide (PBG, 8 μg/kg) was injected into the right atrium. PBG-evoked hypotension, bradycardia, and RSNA reduction were significantly attenuated 5 min after l-NAME. Our results indicate that inhibition of NOS within the NTS attenuates baro- and cardiopulmonary reflexes, suggesting that NO plays a physiologically significant neuromodulatory role in cardiovascular regulation.

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A Novel Rat Model for Comprehensive Microvascular Training of End-to-End, End-to-Side, and Side-to-Side Anastomoses

Journal of Reconstructive Microsurgery ◽

10.1055/s-0039-1679957 ◽

2019 ◽

Vol 35 (07) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

Xiaoliang Yin ◽

Gengfan Ye ◽

Jun Lu ◽

Lijun Wang ◽

Peng Qi ◽

...

Keyword(s):

Animal Model ◽

Average Length ◽

Proximal Part ◽

Distal Portion ◽

Left Renal Artery ◽

Sprague Dawley ◽

Anatomical Dissection ◽

Sprague Dawley Rats ◽

End To End ◽

The Right

Background End-to-end, end-to-side, and side-to-side microvascular anastomoses are the main types of vascular bypass grafting used in microsurgery and neurosurgery. Currently, there has been no animal model available for practicing all three anastomoses in one operation. The aim of this study was to develop a novel animal model that utilizes the rat abdominal aorta (AA), common iliac arteries (CIAs), and the median sacral artery (MSA) for practicing these three types of anastomosis. Methods Eight adult Sprague–Dawley rats were anesthetized and then laparotomized. The AA, MSA, and bilateral CIAs were exposed and separated from the surrounding tissues. The length and diameter of each artery were measured. The relatively long segment of the AA without major branches was selected to perform end-to-end anastomosis. One side of the CIAs (or AA) and MSA were used for end-to-side anastomosis. The bilateral CIAs were applied to a side-to-side and another end-to-side anastomosis. Results Anatomical dissection of the AA, CIAs, and MSA was successfully performed on eight Sprague–Dawley rats; four arterial-to-arterial anastomoses were possible for each animal. The AA trunk between the left renal artery and right iliolumbar arteries was 15.60 ± 0.76 mm in length, 1.59 ± 0.15 mm in diameter, for an end-to-end anastomosis. The left CIA was 1.06 ± 0.08 mm in diameter, for an end-to-side anastomosis with the right CIA. The MSA was 0.78 ± 0.07 mm in diameter, for another end-to-side anastomosis with the right CIA or AA. After finishing end-to-side anastomosis in the proximal part of bilateral CIAs, the distal portion was juxtaposed for an average length of 5.6 ± 0.25 mm, for a side-to-side anastomosis. Conclusion This model can comprehensively and effectively simulate anastomosis used in revascularization procedures and can provide more opportunities for surgical education, which may lead to more routine use in microvascular anastomosis training.

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