The development of capillaries in the rat heart

1983 ◽  
Vol 41 ◽  
pp. 722-723
Author(s):  
Glyn A. Porter
Keyword(s):  
Endothelial Cells ◽  
Umbilical Vein ◽  
Sprague Dawley ◽  
Lamina Densa ◽  
Endothelial Layer ◽  
Adult Rat ◽  
Developing Heart ◽  
Occluding Junctions ◽  
Sprague Dawley Rats ◽  
Heart Capillaries

In the adult rat, studies by others have shown that capillaries of the heart are lined by a continuous endothelial layer. Some other important mural features are : a distinct and continuous lamina densa of the basal lamina, uniformly thick lateral processes of endothelial cells, adhesive and discontinuously occluding junctions between apposing cells. In addition, coated vesicles and pits are rarely seen, while a high proportion of the endothelial luminal and abluminal surfaces, as well as the cytoplasm, is occupied by plasmalemmal vesicles. These vesicles are more frequently found in the lateral processes than in the perikaryon (Fig. 3). It was my purpose in the present study to examine those morphological features of developing heart capillaries known to be important in capillary function in the adult. The hearts of 16, 19 and 21 day fetal and of 1 and 2 day neonatal Sprague- Dawley rats were removed, diced and fixed by immersion in a dilute Karnovsky fixative and processed routinely for TEM. Several fetal hearts (16 and 19 day) were removed and processed similarly 60 seconds after carbon (Pelikan Ink) had been injected into the umbilical vein.

Abstract 637: Hydrogen Sulfide Acts on Endothelial Cells to Elicit Dilation.

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Nancy L Kanagy ◽  
Jessica M Osmond ◽  
Olan Jackson-Weaver ◽  
Benjimen R Walker
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Hydrogen Sulfide ◽  
Mesenteric Arteries ◽  
Direct Effects ◽  
Sprague Dawley ◽  
Imaging Studies ◽  
Knock Out ◽  
Event Frequency ◽  
Sprague Dawley Rats

Hydrogen sulfide (H 2 S), produced by the enzyme cystathionine-γ lyase (CSE), dilates arteries by hyperpolarizing and relaxing vascular smooth muscle cells (VSMC) and CSE knock-out causes hypertension and endothelial dysfunction showing the importance of this system. However, it is not clear if H 2 S-induced VSMC depolarization and relaxation is mediated by direct effects on VSMC or indirectly through actions on endothelial cells (EC). We reported previously that disrupting EC prevents H 2 S-induced vasodilation suggesting H 2 S might act directly on EC. Because inhibiting large-conductance Ca 2+ -activated K + (BK Ca ) channels also inhibits H 2 S-induced dilation, we hypothesized that H 2 S activates EC BK Ca channels to hyperpolarize EC and increase EC Ca 2+ which stimulates release of a secondary hyperpolarizing factor. Small mesenteric arteries from male Sprague-Dawley rats were used for all experiments. We found that EC disruption prevented H 2 S-induced VSMC membrane potential ( E m ) hyperpolarization. Blocking EC BK Ca channels with luminal application of the BK Ca inhibitor, iberiotoxin (IbTx, 100 nM), also prevented NaHS-induced dilation and VSMC hyperpolarization but did not affect resting VSMC E m showing EC specific actions. Sharp electrode recordings in arteries cut open to expose EC demonstrated H 2 S-induced hyperpolarization of EC while Ca 2+ imaging studies in fluor-4 loaded EC showed that H 2 S increases EC Ca 2+ event frequency. Thus H 2 S can act directly on EC. Inhibiting the EC enzyme cytochrome P 450 2C (Cyp2C) with sulfaphenazole also prevented VSMC depolarization and vasodilation. Finally, inhibiting TRPV4 channels to block the target of the Cyp2C product 11,12-EET inhibited NaHS-induced dilation. Combined with our previous report that CSE inhibition decreases BK Ca currents in EC, these results suggest that H 2 S stimulates EC BK Ca channels and activates Cyp2C upstream of VSMC hyperpolarization and vasodilation.

Ontogeny of glycine transport in isolated rat renal tubules

1977 ◽  
Vol 233 (3) ◽  
pp. F241-F246
Author(s):  
K. S. Roth ◽  
S. M. Hwang ◽  
J. W. London ◽  
S. Segal
Keyword(s):  
Rat Kidney ◽  
Renal Tubules ◽  
Sprague Dawley ◽  
Entry Rate ◽  
Glycine Uptake ◽  
Adult Rat ◽  
High Affinity ◽  
Sprague Dawley Rats ◽  
Rate Kinetics ◽  
Isolated Renal Tubule

Isolated renal tubule preparations were made from newborn Sprague-Dawley rats and used to study initial entry rate kinetics of glycine. The results were compared to those obtained in the isolated tubule preparation from the adult rat kidney. While initial rates of glycine uptake were identical for newborn and adult tubules, significant differences in influx kinetics were demonstrated. Of the two apparent transport Km systems shown to be present in the newborn tubule, the high-affinity, low-capacity system accounts for about 40% of total glycine uptake at physiologic concentrations. The high-affinity, low-capacity system of the adult tissue accounts for about 10% of total uptake at the same concentration range. The data lend strength to the argument against the concept that the physiologic hyperglycinuria of the newborn rat is due to either impaired ability to concentrate glycine intracellularly or to absence of one or more transport mechanisms for glycine.

scholarly journals Evidences Suggesting that Distinct Immunological and Cellular Responses to Light Damage Distinguishes Juvenile and Adult Rat Retinas

2019 ◽  
Vol 20 (11) ◽  
pp. 2744
Author(s):  
Anna Polosa ◽  
Shasha Lv ◽  
Wassila Ait Igrine ◽  
Laura-Alexie Chevrolat ◽  
Hyba Bessaklia ◽  
...  
Keyword(s):  
Immune System ◽  
Light Exposure ◽  
Age Related Macular Degeneration ◽  
Light Damage ◽  
Sprague Dawley ◽  
Adult Rat ◽  
Age Related ◽  
Degenerative Disorders ◽  
Sprague Dawley Rats ◽  
Dose Dependent

To unravel the mechanisms behind the higher resistance to light damage of juvenile (JR) versus adult (AR) rats, Sprague Dawley rats were exposed to a bright luminous environment of 10, 000 lux. The light-induced retinopathy (LIR) was assessed with histology, electroretinography and immunohistochemistry (IHC). In JR, 2 days of exposure induced the typical LIR, while >3 days added little LIR. IHC revealed a subtle migration of microglia (Iba1 marker) from the inner to the outer retina after 3 days of exposure in JR contrasting with the stronger reaction seen after 1 day in AR. Similarly, in JR, the Müller cells expressed less intense GFAP, CNTF and FGF2 staining compared to AR. Our results suggest that in JR the degree of retinal damage is not proportional to the duration of light exposure (i.e., dose-independent retinopathy), contrasting with the dose-dependent LIR reported in AR. The immature immune system in JR may explain the delayed and/or weaker inflammatory response compared to AR, a finding that would also point to the devastating contribution of the immune system in generating the LIR phenotype, a claim also advanced to explain the pathophysiology of other retinal degenerative disorders such as Age-related Macular Degeneration, Diabetic Retinopathy and Retinitis Pigmentosa.

Regression of white adipose tissue in diabetic rats

1989 ◽  
Vol 257 (4) ◽  
pp. E547-E553 ◽  
Author(s):  
A. Geloen ◽  
P. E. Roy ◽  
L. J. Bukowiecki
Keyword(s):  
Endothelial Cells ◽  
Adipose Tissue ◽  
Protein Content ◽  
Cell Number ◽  
Diabetic Rats ◽  
Total Protein Content ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Wet Weight

The effects of long-term diabetes (4 wk) on the development of parametrial (PWAT) and retroperitoneal (RWAT) white adipose tissues were studied in young Sprague-Dawley rats (170-200 g) injected with a single dose of streptozotocin (75 mg/kg). Diabetes stopped animal growth and totally abolished the normal increases in the wet weight, total protein content, and cellularity (estimated by DNA content) of PWAT and RWAT. Remarkably, the prolonged lack of insulin induced a progressive decrease of the cellularity of RWAT to levels that were lower than those of the initial controls. It also resulted in a marked reduction of adipocyte size. The tiny adipocytes seen in diabetic animals were characterized by the presence of multilocular triglyceride droplets. In general, the decreases in cell number, cell size, and protein content were more pronounced in RWAT than in PWAT. Quantitative cellular frequency studies revealed that adipocytes, and possibly also endothelial cells, contribute to the decrease in RWAT cellularity. The results demonstrate that 1) diabetes inhibits proliferative activity in adipose tissue, 2) total cell number reduction may occur in adipose depot of young growing rats, 3) this effect is depot dependent, and 4) the turnover of adipocytes and endothelial cells is relatively slow (several weeks).

scholarly journals 5-Hydroxytryptamine (5HT) Receptors in the Heart Valves of Cynomolgus Monkeys and Sprague-Dawley Rats

2005 ◽  
Vol 53 (5) ◽  
pp. 671-677 ◽  
Author(s):  
Chandikumar S. Elangbam ◽  
Ruth M. Lightfoot ◽  
Lawrence W. Yoon ◽  
Donald R. Creech ◽  
Robert S. Geske ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Heart Valves ◽  
Cell Types ◽  
Positive Staining ◽  
Normal Heart ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Positive Immunostaining ◽  
5Ht2c Receptor ◽  
Polymerase Chain

5-Hydroxytryptamine-2B receptor (5HT2BR) stimulation is known to cause fibroblast mitogenesis, and the mitogenic effect has been proposed to trigger valvular heart disease in humans. In this study, we used real-time polymerase chain reaction (TaqMan) to quantify transcript levels of 5HT2B, 5HT2C, and 5HT1B receptors and immunohistochemistry (IHC) to detect the tissue localization of these receptors in the normal heart valves of cynomolgus (CM) monkeys and Sprague-Dawley (S-D) rats. In both species, positive immunostaining was noted for 5HT1B and 5HT2B receptors in mitral, tricuspid, aortic, and pulmonary valves, and the cell types showing positive staining were interstitial cells and endothelial cells lining the valve leaflet. In CM monkeys, 5HT2CR was expressed only in the endothelial cells lining the leaflet, whereas S-D valves were negative for this receptor. IHC results were correlated with 5HT2B and 5HT1B receptor transcripts for all four valves. However, 5HT2C receptor transcripts were lower than 5HT2B or 5HT1B in all CM monkey valves, whereas 5HT2C transcripts were below the level of detection in any of the S-D rat valves. Our data showed the expression of 5HT2B, 5HT1B, and 5HT2C receptors in the normal heart valves of CM monkeys and S-D rats, and IHC and TaqMan techniques may be used to study the potential mechanism of compounds with 5HT2BR agonist activity.

scholarly journals Therapeutic Effects of Water Soluble Danshen Extracts on Atherosclerosis

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Yoon Hee Cho ◽  
Cheol Ryong Ku ◽  
Zhen-Yu Hong ◽  
Ji Hoe Heo ◽  
Eun Hee Kim ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Platelet Aggregation ◽  
Ex Vivo ◽  
Umbilical Vein ◽  
Water Soluble ◽  
Therapeutic Effects ◽  
Sprague Dawley ◽  
Tail Vein ◽  
Vein Thrombosis

Danshen is a traditional Chinese medicine with many beneficial effects on cardiovascular diseases. The aim of this study was to evaluate the mechanisms responsible for the antiatherogenic effect of water soluble Danshen extracts (DEs). Rat vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs) were treated with DE. To evaluate the effects of DEin vivo, carotid balloon injury and tail vein thrombosis were induced in Sprague-Dawley (SD) rats and iliac artery stent was induced in New Zealand white rabbits. The inhibitory action of DE on platelet aggregation was confirmed with an impedance aggregometer. DE inhibited the production of reactive oxygen species, and the migration and proliferation of platelet-derived growth factor-BB stimulated VSMCs. Furthermore, DE prevented inflammation and apoptosis in HUVECs. Both effects of DE were reconfirmed in both rat models. DE treatment attenuated platelet aggregation in bothin vivoandex vivoconditions. Pretreatment with DE prevented tail vein thrombosis, which is normally induced byκ-carrageenan injection. Lastly, DE-treated rabbits showed decreased in-stent restenosis of stented iliac arteries. These results suggest that water soluble DE modulates key atherogenic events in VSMCs, endothelial cells, and platelets in bothin vitroandin vivoconditions.

scholarly journals Manganese exposure induces permeability in renal glomerular endothelial cells via the Smad2/3-Snail–VE-cadherin axis

2020 ◽  
Vol 9 (5) ◽  
pp. 683-692
Author(s):  
Peng Gao ◽  
Yutian Tian ◽  
Qi Xie ◽  
Liang Zhang ◽  
Yongjian Yan ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Zinc Finger Protein ◽  
Vascular Endothelial ◽  
Sprague Dawley ◽  
Glomerular Diseases ◽  
Cell Monolayers ◽  
Vascular Endothelial Cadherin ◽  
Glomerular Endothelial Cells ◽  
Sprague Dawley Rats ◽  
Glomerular Endothelium

Abstract Manganese (Mn) is an essential micronutrient. However, it is well established that Mn overexposure causes nervous system diseases. In contrast, there are few reports on the effects of Mn exposure on glomerular endothelium. In the present study, the potential effects of Mn exposure on glomerular endothelium were evaluated. Sprague Dawley rats were used as a model of Mn overexposure by intraperitoneal injection of MnCl2·H2O at 25 mg/kg body weight. Mn exposure decreased expression of vascular endothelial-cadherin, a key component of adherens junctions, and increased exudate from glomeruli in Sprague Dawley rats. Human renal glomerular endothelial cells were cultured with different concentration of Mn. Exposure to 0.2 mM Mn increased permeability of human renal glomerular endothelial cell monolayers and decreased vascular endothelial-cadherin expression without inducing cytotoxicity. In addition, Mn exposure increased phosphorylation of mothers against decapentaplegic homolog 2/3 and upregulated expression of zinc finger protein SNAI1, a negative transcriptional regulator of vascular endothelial-cadherin. Our data suggest Mn exposure may contribute to development of glomerular diseases by inducing permeability of glomerular endothelium.

SERUM 5α-ANDROSTANE-3α,17β-DIOL, ANDROSTERONE AND TESTOSTERONE CONCENTRATIONS IN THE IMMATURE MALE RAT: INFLUENCE OF TIME OF DAY

1977 ◽  
Vol 75 (1) ◽  
pp. 177-178 ◽  
Author(s):  
W. H. MOGER ◽  
P. R. MURPHY
Keyword(s):  
Serum Testosterone ◽  
Temporal Variations ◽  
Time Of Day ◽  
Male Rats ◽  
Male Rat ◽  
Sprague Dawley ◽  
Circadian Variations ◽  
Adult Rat ◽  
Immature Male ◽  
Sprague Dawley Rats

Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada, B3H 4H7 (Received 22 April 1977) The concentration of testosterone in the serum of the adult rat varies significantly over a 24 h period (Kinson & Lui, 1973; Howland, 1975; Wilson, McMillan, Seal & Ahmed, 1976). However, studies on circadian variations in serum testosterone concentrations in immature male rats have yielded conflicting results. Grotjan & Johnson (1976) reported significant changes with time in 25–26-day-old Holtzman rats, whereas Döhler & Wuttke (1976) did not observe significant changes in 13–18 or 25–30-day-old Sprague–Dawley rats maintained on the same lighting schedule (14 h light: 10 h darkness). Recently we reported that from 20–35 days of age, 5α-androstane-3α,17β-diol (androstanediol) is the predominant androgen in the circulation of male rats (Moger, 1977). This study was undertaken to determine temporal variations in the concentrations of androstanediol, androsterone and testosterone. Forty-nine male Sprague

A collagen-based sealant to prevent in vivo reformation of epidural scar adhesions in an adult rat laminectomy model

2002 ◽  
Vol 97 (1) ◽  
pp. 69-74 ◽  
Author(s):  
Song Liu ◽  
Jean Pierre Boutrand ◽  
Jacques Bittoun ◽  
Marc Tadie
Keyword(s):  
Histological Evaluation ◽  
Sprague Dawley ◽  
Nerve Roots ◽  
Content Type ◽  
Adult Rat ◽  
Sprague Dawley Rats ◽  
The Reformation ◽  
White Tissue ◽  
Fine Print

Object. The authors investigated the effect of a collagen-based sealant, Gel Amidon Oxydé (GAO), in preventing the reformation of epidural scar adhesions in an adult rat model of laminectomy. Methods. Thirty-two adult Sprague—Dawley rats underwent a complete L5–6 laminectomy, after which the dura mater was exposed and the left adjacent L-4 and L-5 nerve roots were exposed. The surgical wound was then closed; 1 month later it was reopened. The epidural scar adhesions that developed were observed and carefully removed, leaving clean dura and nerve roots reexposed. In 16 experimental rats, GAO was placed onto the reexposed dura and around the nerve roots before it polymerized. No treatment was performed in 16 control rats. Postoperatively, all rats were healthy and without neurological deficit. The incisions healed within 1 week regardless of the treatment with the GAO. Three months after reoperation, magnetic resonance imaging revealed that important epidural adhesions were present in the control rats but not in the experimental rats. These findings were then confirmed by gross anatomical examination in which a white tissue layer was found over the dura without adhesions in the experimental animals, whereas significant epidural scar adhesions were demonstrated in the controls. Histological evaluation of the laminectomy site also showed that the peridural space in the experimental rats was larger than that in the controls. Conclusions. The authors found that GAO may be a safe and effective antiscarring adhesion biomaterial in vivo. When placed into the laminectomy site, GAO may prove beneficial in preventing the formation and reformation of epidural scar adhesions in humans.

Hypothyroidism increases serotonin turnover and sympathetic activity in the adult rat

1991 ◽  
Vol 69 (2) ◽  
pp. 205-210 ◽  
Author(s):  
W. N. Henley ◽  
X. Chen ◽  
C. Klettner ◽  
L. L. Bellush ◽  
M. A. Notestine
Keyword(s):  
Recovery Period ◽  
Normalization Procedure ◽  
Sprague Dawley ◽  
Creatinine Excretion ◽  
Adult Rat ◽  
Sympathetic Function ◽  
Sham Surgery ◽  
Sprague Dawley Rats ◽  
Serotonin Turnover ◽  
Colonic Temperature

Adult, male Sprague–Dawley rats underwent surgical thyroidectomy (Tx) or sham surgery. In all three experiments from which data are reported, a 3-week recovery period was allowed. In experiments I and II, baseline measurements of colonic temperature (Tc) and urinary norepinephrine excretion (NE) were obtained, and both variables were monitored daily for the duration of the studies. After baseline measurements, half of each surgical group was given either triiodothyronine (T3) or vehicle injections subcutaneously; in experiment I replacements continued for 1.5 days, while in experiment II T3 replacement continued for 3.5 days. Rats were decapitated at the end of each experiment and serotonin (5-HT) turnover was measured in brainstem. Serotonin turnover in rostral and caudal brainstem was increased with Tx (p < 0.05). Increased turnover in caudal brainstem was normalized by T3 only in experiment II. Similarly, decreased Tc and elevated NE with Tx were normalized in experiment II but not in experiment I. In experiment III, NE measurements normalized on a creatinine excretion basis indicated that increased NE is evident with Tx, irrespective of normalization procedure. Significant correlations between 5-HT in caudal brainstem and metabolic correlates of sympathetic function, concurrent normalization of NE and 5-HT in caudal brainstem, plus work from other laboratories describing sympathoexcitatory serotonergic neurons located in me caudal brainstem suggest that the central and peripheral changes in me hypothyroid rat are causally related.Key words: triiodothyronine, norepinephrine, serotonin, brainstem, metabolism.

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