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| | [No title] |
 | | The process may be myogenic, meaning that as the afferent arteriole is stretched, calcium channels are opened, which cause smooth muscle contraction. | | | This means the GFR is increased relative to where it was before the contraction, but overall the GFR is still lower than it would be in a non CHF patient. | | | The macula densa then sends prostaglandins and/or NO to dilate the afferent arteriole to increase RPF. |
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http://www.muhealth.org/~md2003/draft7/1-22kidney.doc
(1090 words)
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| | Karger Publishers |
| | preferential relaxation of the afferent arteriole, was also observed during norepinephrine-induced vasoconstriction [15]. | | | Furthermore, the assessment of renal arteriolar resistance with the use of renal function curves indicates an efferent arteriolar dilation by benidipine in human nondiabetic nephropathy [56]. | | | In contrast, no subunit is found in cortical efferent arterioles, although these channel subunits are expressed at juxtamedullary efferent arterioles. |
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http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowFulltext&ProduktNr=223979&Ausgabe=229258&ArtikelNr=72054
(7820 words)
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| | [No title] |
| | Through the efferent arteriole the oncotic pressure does not change, again because arterioles are not permeable to water. | | | Because the pressure gradient is proportional to flow, and as we decrease the flow through the afferent arteriole, the pressure goes down. | | | Blood flow is drastically reduced, however, from constriction of both arterioles. |
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http://www.uhmc.sunysb.edu/som/students/2002/2002Web/Lectures/Organs/Organs27.doc
(2742 words)
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| | Videomicroscopy Library |
| | Norepinephrine-induced constriction of a 50-micron diameter arteriole in rat cremaster muscle. | | | Blood flow in a 50-micron diameter venule from rat cremaster muscle. | | | Intermediate magnification micrograph showing capillary network in rat cremaster muscle (capillary diameter is 4-6 microns). |
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http://mphywww.tamu.edu/video_library.html
(831 words)
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| | arteriole - definition from Biology-Online.org |
| | Arterioles are responsible for carrying oxygenated blood from the heart to all over the body. | | | These arterioles get progressively smaller the more distanced they are from the heart, as most of the blood supply is required by the major organs positioned close to the heart and is provided by the arteries. |
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http://www.biology-online.org/dictionary/Arteriole
(73 words)
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| | LaserNewsv3 |
| | This is observed in the ease of treatment of essential telangiectasia on the foot and lower leg with any type of vascular laser, and contrasts with the response of venous ectasia at the same site requiring high-energy longer pulse widths and cooling. | | | Why are even the finest venous flares on the leg so difficult with the same laser parameters and techniques that work well for most facial telangiectasia? | | | The spider nevus is exquisitely sensitive to PDL therapy because the direction of flow is from larger to finer vessels, allowing trapping of emboli. |
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http://www.lasernews.net/lasernews/lasernewsv3.nsf/default/9216A676D097F83488256914006AE35B
(1077 words)
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| | Spotting the connection |
| | Harris says that the next step in the research program will be to develop the physical and mathematical theory that can accurately describe the relationship between the arteriole/venule pairing and capillary permeability in order to allow a much more complete characterization of the inflammatory response in a variety of situations. | | | Norman Harris, assistant professor of bioengineering and director of the project, says, "Our finding is that communication between pairs of venules and arterioles facilitates signaling to capillaries to release the fluid which causes swelling into the tissues. | | | Subsequent experiments, in which the micropressure in the capillary was measured, showed that increased fluid release was the result of an increase in permeability. |
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http://www.engr.psu.edu/newsevents/EPS/v17n1_2000fall/spot.htm
(724 words)
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| | Myosin heavy chain expression in renal afferent and efferent arterioles: relationship to contractile kinetics and ... |
| | Using RT-PCR, Western analysis, and immunofluorescence imaging of intact isolated arterioles, we found that the afferent arteriole predominantly expresses the MHC-B isoform, whereas the efferent arteriole expresses only the slower-cycling MHC-A isoform. | | | Our findings thus point to the renal microcirculation as a unique and important example of smooth muscle adaptation in regard to MHC isoform expression and physiological function. | | | In the present study, we examined MHC expression patterns in renal afferent and efferent arterioles. |
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http://www.fasebj.org/cgi/content/abstract/03-0096fjev1
(321 words)
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| | II. Blood Flow and Filtration |
| | It is apparent then, that resistance upstream from the glomerular capillaries in the afferent arteriole must change as renal artery pressure changes. | | | To regulate both it seems obvious that the major change in resistance must occur in which arteriole? | | | Efferent arteriolar resistance may change also, but it is obvious that the major change occurs in the afferent arteriole. |
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http://www2.kumc.edu/ki/physiology/course/two/2_8.htm
(544 words)
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| | [No title] |
| | With an increase in resistance, RBF decreases and there will be either no change or slight increase in GFR b/c PGC upstream tends to increase The peritubular capillary reabsorption system can be altered by changes in oncotic or hydrostatic pressures. | | | GFR and RBF tend to maintain constancy despite wide variations in perfusion pressure This tells us that the main change in vascular resistance occurs in the afferent arteriole (since changes in RBF and GFR are similar). | | | For example, in early CHF, there tends to be maintenance of GFR but a reduction in RBF and because of that, there is a decrease in the hydrostatic pressure in the peritubular system (say from 20 to 18) b/c increased resistance at the efferent arteriole. |
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http://www.muhealth.org/~md2003/update7/1-22kidney.doc
(1187 words)
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| | Smooth Muscle Research Group - Rodger Loutzenhiser |
| | Our laboratory alsodeveloped a novel technique for obtaining intact afferent and efferent arterioles from the normal rat kidney, and we routinely obtain freshly dispersed myocytes from single arterioles of each type. | | | recently developed techniques will help to further define the molecular basis for the differing properties of the afferent and efferent arterioles. | | | We originated the in vitro perfused hydronephrotic rat kidney model, which we use to study contractile responses, and have further modified to examine membrane potential responses of the afferent and efferent arterioles in situ. |
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http://www.ucalgary.ca/smrg/rodger.htm
(993 words)
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| | Rodger D. Loutzenhiser |
| | General interests centre on mechanisms regulating vascular smooth muscle contractility and the determinants of vascular reactivity in the renal microcirculation. | | | cGMP-dependent and cGMP-independent actions of exogenous and endogenous NO on the renal afferent arteriole. | | | In contrast, vasoconstrictor responses of the efferent arteriole are insensitive to Ca antagonists. |
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http://www.ucalgary.ca/smrg/loutzenhiser.htm
(478 words)
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| | Arteriole - Wikipedia, the free encyclopedia |
| | This decreases the resistance to flow into peripheral vascular beds, lowering overall systemic pressure. | | | The muscular contraction of arterioles is targetted by drugs that lower blood pressure (antihypertensives), for example the dihydropyridines (nifedipine and nicardipine), which block the calcium conductance in the muscular layer of the arterioles, causing relaxation. | | | The mean blood pressure in the arteries supplying the body is a result of the interaction between the cardiac output (the volume of blood the heart is pumping per minute) and the vascular resistance, usually termed total peripheral resistance by physicians and researchers. |
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http://en.wikipedia.org/wiki/Arteriole
(210 words)
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| | [No title] |
| | Finally, note that the tunica media of smooth muscle within the arteriole is much more prominent and regularly arranged than that of the accompanying venule. | | | Venules may be distinguished from accompanying arterioles by their larger, irregular-shaped lumens which are usually filled with blood, and their thinner walls. | | | [11-1371]: This slide is a cross-section through an arteriole. |
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http://www.georgetown.edu/dml/educ/micro/cardio/cardio.txt
(1588 words)
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| | APStracts 2:0222H, 1995. |
| | Our purpose was to investigate blood flow responses to local and conducted vasodilation in arteriole networks supplying the cremaster muscle of anaesthetized (pentobarbital) male hamsters. | | | Thus, dilation of a distal arteriole segment alone had no effect on muscle blood flow. | | | Conducted vasodilation elevates flow in arteriole networks of hamster striated muscle. |
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http://www.uth.tmc.edu/apstracts/1995/heart/May/222h.html
(335 words)
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| | Renal Test #1 |
| | Constriction of the renal afferent glomerular arterioles tends to ___________ glomerular capillary hydrostatic pressure and __________ renal blood flow. | | | An acute increase in the NaCl concentration in the early distal tubule results in a signal from the macula densa that tends to: | | | Constrict both the afferent and efferent glomerular arterioles |
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http://human.physiol.arizona.edu/CGI/RenalTest1.html
(273 words)
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| | Venules |
| | Examine the venules that accompany the arterioles already observed in the slides above. | | | The arteriole has some smooth muscle associated with it, yet the wall of the venule (white arrows) is relatively bare from cells and very thin. | | | Also notice the lack of rigidity in the structure of the vein compared to the arteriole. |
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http://www3.umdnj.edu/histsweb/lab7/lab7venules.html
(146 words)
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| | Archives of Pathology & Laboratory Medicine: Morphometric and electron microscopic analyses of the effect of ... |
| | Small arteriole walls were thickest in myomas from GnRHA treated patients and thinnest in premenopausal controls. | | | Patients.-A total of 30 patient samples were studied, with 3 groups comprising 10 samples each, including patients treated with GnRHAs, age-matched control patients, and postmenopausal women. | | | Electron micrographs were made of random arterioles from the first 2 groups (GnRHA-treated patients and age-matched controls). |
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http://www.findarticles.com/p/articles/mi_qa3725/is_200009/ai_n8924548
(1252 words)
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| | Dorlands Medical Dictionary |
| | sis) necrosis of arterioles, as may be seen in nephrosclerosis; called also arteriolar necrosis. | | | Hyaline arteriolosclerosis, in which there is homogeneous pink hyaline thickening of the arteriolar walls, is associated with benign nephrosclerosis. | | | cyclosporine-associated arteriopathy, a manifestation of chronic cyclosporine-induced nephrotoxicity, consisting of hyaline degeneration of the tunica media and mucoid thickening of the intima of the arterioles of the peripheral vascular tree. |
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http://www.mercksource.com/pp/us/cns/cns_hl_dorlands.jspzQzpgzEzzSzppdocszSzuszSzcommonzSzdorlandszSzdorlandzSzdmd_a_62zPzhtm
(2599 words)
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| | Hoa T. Le Page of Renal Circulation |
| | The second mechanism is a flow dependent mechanism known as tubuloglomerular feedback. | | | The first mechanism via a pressure sensitive myogenic mechanism, which is related to an intrinsic muscle property of vascular smooth muscle, which surrounds the aforementioned vessels: the tendency to contract when stretched. | | | Blood flow is controlled by adjusting vascular resistance, e.g. |
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http://www.usc.edu/dept/biomed/bme403/Section_3/renal_circulation.html
(535 words)
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| | Arteriole |
| | arteriole is called a "precapillary arteriole" because of the number of smooth muscle | | | Two arterioles showing the great variation in size that is possible. |
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http://cellbio.utmb.edu/microanatomy/arteriole.htm
(36 words)
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| | KSUCVM - A&P - Cell Physiology Lab - Perfused Arteriole |
| | The perfused preparation is used for the study of myogenic control of vascular diameter and for the determination of the pressure-dependence of vasoconstrictions. | | | Arterioles are perfused with a set of concentric pipettes. | | | KSUCVM - AandP - Cell Physiology Lab - Perfused Arteriole |
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http://www.vet.ksu.edu/DEPTS/AP/wange/perf.htm
(76 words)
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| | Virtual Hospital: Atlas of Microscopic Anatomy: Section 1 - Cells |
| | The peripheral nerve is enclosed in a connective tissue sheath and is formed by a number of nerve fibers. | | | This figure shows a commonly seen triad: a peripheral nerve, an arteriole, and a venule. | | | The venule seen here is smaller than the adjacent arteriole. |
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http://www.vh.org/adult/provider/anatomy/MicroscopicAnatomy/Section08/Plate08154.html
(204 words)
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| | stticpee |
| | , note that there are two arterioles feeding into and out of the glomerulus: Arteriole 1 (the afferent arteriole) and Arteriole 2 (the efferent arteriole). | | | This takes into account two pressures: the Blood Hydrostatic Pressure (BHP) and the Blood Osmotic Pressure (BOP). | | | The tables, below, summarize the effects of constricting or dilating these arterioles on the BHP: |
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http://tooldoc.wncc.nevada.edu/hydro.htm
(759 words)
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| | REGULATION OF GLOMERULAR FILTRATION BY THE KIDNEY |
| | There is also some myogenic control and over-expansion of the afferent arterioles will lead to their constriction; this local myogenic response help protect afferent arterioles, and the glomeruli downstream, from overstretch or rupture in the face of elevated blood pressure. | | | Using this juxtaglomerular apparatus, individual nephrons have the ability to maintain relatively constant perfusion pressures such that consistency of overall renal function is normally well maintained. | | | This prevents increased perfusion so that GFR will not be increased in the face of routine increases in b.p. |
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http://faculty.etsu.edu/currie/renalpressure.htm
(755 words)
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| | arterioles |
| | This is another example of a smaller arteriole and vein. | | | The reason we can call this an arteriole is because of the very few layers of smooth muscle in the tunica media pointed out by the blue arrow. | | | The yellow arrows are pointing out the smooth muscle cells, that are located in the tunica media, and because there is only one layer of them, we can classify it as an arteriole. |
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http://www3.umdnj.edu/histsweb/lab7/lab7arterioles.html
(254 words)
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| | Arteriole |
| | In Lab 2, I told you that structure A is an arteriole. | | | You now know that because there are only one or two layers of smooth muscle in the tunica media. | | | Although one cannot identify veins by the layers of muscle in the wall, you can be confident that a small vein will generally accompany a small artery, and a venule will accompany an arteriole, and so on (although with the muscular and elastic arteries, they are called medium and large veins, respectively). |
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http://www.vetmed.wsu.edu/Van308/arteriol.htm
(83 words)
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| | Efferent Arteriole |
| | Because of its smaller diameter than the afferent arteriole, it creates some resistance to blood flow, producing the back-up of blood in the glomerulus which creates higher pressure in the glomerular cavity. | | | The efferent arteriole carries blood away from the glomerulus. |
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http://www.innerbody.com/text/card80.html
(41 words)
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| | Histology IJS (1) |
| | It is possible that these are passing to supply the arteriolar muscle. | | | The tunica media is represented by a single layer of smooth muscle cells (M). | | | The arteriole is lined by an epithelium (E) forming the tunica intima of the arteriole. |
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http://www.abdn.ac.uk/~bms027/TH1.H1.4D1.html
(101 words)
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