Effects of renal receptor stimulation on neurons within the ventrolateral medulla of the cat

1993 ◽  
Vol 265 (2) ◽  
pp. R290-R301 ◽  
Author(s):  
M. A. Vizzard ◽  
A. Standish ◽  
W. S. Ammons
Keyword(s):  
Renal Artery ◽  
Renal Vein ◽  
Receptor Activation ◽  
Artery Occlusion ◽  
Ventrolateral Medulla ◽  
Receptor Stimulation ◽  
Renal Artery Occlusion ◽  
Renal Receptor ◽  
Excitatory Responses ◽  
Alpha Chloralose

Experiments were performed to determine if activation of renal receptors by occlusion of the renal artery, renal vein, or ureter would alter activity of cells within the ventrolateral medulla of the cat. Extracellular unit recordings were obtained from 195 cells located within the rostral ventrolateral medulla of 90 alpha-chloralose-anesthetized cats. Fifty-five of 195 cells (28.2%) tested for responses to renal receptor activation responded to at least one of the occlusions. Occlusion of the ureter increased the activity of 25 cells from 9.7 +/- 3.7 to 23.0 +/- 6.5 impulses/s and decreased the activity of 5 cells from 11.9 +/- 3.6 to 3.5 +/- 1.2 impulses/s. Occlusion of the renal vein increased the activity of seven cells from 7.5 +/- 3.3 to 22.3 +/- 7.3 impulses/s and decreased the activity of six cells from 13.8 +/- 3.8 to 4.1 +/- 2.0 impulses/s. Renal artery occlusion elicited solely excitatory responses from 43 cells. Thirty-one of the 43 cells increased their activity within 0-3 s of the onset of renal artery occlusion from 4.1 +/- 0.8 to 12.6 +/- 1.2 impulses/s. Renal artery occlusion increased the activity of 10 out of 43 cells with a mean latency of 26.1 +/- 6.5 s from 8.3 +/- 2.5 to 29.6 +/- 9.3 impulses/s. Twenty-four of the 55 (43.6%) responders were responsive to two or more forms of renal receptor activation. These results demonstrate that activation of renal mechanoreceptors and chemoreceptors affects cells within the ventrolateral medulla of the cat.(ABSTRACT TRUNCATED AT 250 WORDS)

Responses of thoracolumbar spinal neurons to renal artery occlusion

1989 ◽  
Vol 256 (6) ◽  
pp. H1515-H1523 ◽  
Author(s):  
W. S. Ammons ◽  
R. Sinha
Keyword(s):  
Electrical Stimulation ◽  
Renal Artery ◽  
Artery Occlusion ◽  
Renal Ischemia ◽  
Renal Nerves ◽  
Spinal Neurons ◽  
Renal Artery Occlusion ◽  
C Fiber ◽  
Alpha Chloralose ◽  
Stimulation Of

Experiments were performed to examine responses of spinal neurons to activation of renal chemoreceptors during renal artery occlusion (RAO). One hundred twenty-two spinal neurons were studied in 33 cats that were anesthetized with alpha-chloralose. Cells studied in the L2-T11 segments were excited by electrical stimulation of the renal nerves and responded to stimulation of somatic structures. RAO (90 s) excited 67 cells (55%). Twenty-eight cells were excited at the onset of occlusion (from 5 +/- 1 to 27 +/- 5 spikes/s) and then either completely or partially adapted (ON responses). Another 39 cells were excited at the onset of occlusion, adapted to varying degrees, and then exhibited a second increase in activity beginning 41 +/- 7 s into the occlusion period [onset-ischemic (ON/IS) responses]. The secondary increase reached a peak of 15 +/- 2 spikes/s 65 s after occlusion. Among the responding cells, ON responses were associated with cells receiving A delta only or with cells with A delta- and C-fiber renal inputs. In contrast, 100% of cells with ON/IS response received both A delta- and C-fiber inputs. Probability of finding responding cells was greatest in the most rostral segments. We conclude that ON responses to RAO are due to activation of mechanoreceptors in the renal artery. ON/IS responses must have resulted from activation of mechanoreceptors followed by activation of renal chemoreceptors in association with development of renal ischemia. These data provide evidence for activation of spinal neurons by RAO. These neurons may be important for renal reflexes of chemoreceptor origin.

Bowditch Lecture. Renal afferent inputs to ascending spinal pathways

1992 ◽  
Vol 262 (2) ◽  
pp. R165-R176 ◽  
Author(s):  
W. S. Ammons
Keyword(s):  
Renal Vein ◽  
Splanchnic Nerve ◽  
Artery Occlusion ◽  
Ventrolateral Medulla ◽  
Cardiovascular Reflexes ◽  
Medullary Reticular Formation ◽  
Renal Nerve ◽  
C Fibers ◽  
Afferent Fibers ◽  
Excitatory Responses

Studies of renal afferent fibers and their functions have continued since the work of Pines in 1959 (Fiziol. Zh. SSSR Im. I M Sechenova 45: 1339-1347, 1959). The kidney contains mechanoreceptors and chemoreceptors that appear to have two major functions. First, renal mechano- and chemoreceptors evoke a variety of renorenal reflexes, while more global cardiovascular reflexes are primarily evoked by renal mechanoreceptors. A second function of renal afferent fibers is to cause the pain of renal disease. Recent studies suggest that renal afferent fibers may also regulate secretion of vasopressin from the pituitary gland. Substantial evidence indicates that, although most renal afferent fibers enter the spinal cord, their functions depend to a large extent on supraspinal circuitry. Thus our research has focused on defining characteristics of spinal neurons that relay renal information to the brain. In the cat, neurons in the L2-T11 segments with excitatory responses to renal A delta and C fiber input project to the medial medullary reticular formation and to the caudal and rostral ventrolateral medulla. Renal afferent information reaches these cells by way of the least splanchnic nerve and by way of more than one dorsal root. In the monkey spinothalamic neurons in the L3-T10 segments respond to renal nerve stimulation. Excitatory responses predominate, but inhibitory responses occur in L2 and L3. These cells also respond to renal A delta and C fibers. Stimulation of renal mechanoreceptors by occlusion of the ureteropelvic junction or renal vein excites feline spinoreticular neurons. Graded increases in renal vein pressure produce graded increases in cell responses. Activation of renal chemoreceptors increases activity of spinal interneurons. Within the L2-T11 segments, cells responding to ureteral occlusion are located caudally, cells with responses to renal artery occlusion are located rostrally, and cells responding to renal vein occlusion are located in between. The differential locations of cells with these inputs suggests the existence of a coding mechanism for different renal receptor populations. Distention of the renal pelvis is a potent stimulator of primate spinothalamic neurons. These neurons encode renal pelvic pressures in the noxious range and appear to be important in mechanisms of renal pain.

scholarly journals Osteogenesis imperfecta with right renal artery occlusion

2012 ◽  
Vol 2012 (sep05 2) ◽  
pp. bcr2012006536-bcr2012006536 ◽  
Author(s):  
A. K. Vaish ◽  
N. Kumar ◽  
N. Jain ◽  
A. Agarwal
Keyword(s):  
Osteogenesis Imperfecta ◽  
Renal Artery ◽  
Artery Occlusion ◽  
Renal Artery Occlusion

Renal Function Salvage After Delayed Endovascular Revascularization of Acute Renal Artery Occlusion in Patients With Fenestrated-Branched Endovascular Aneurysm Repair or Visceral Debranching

2018 ◽  
Vol 25 (4) ◽  
pp. 466-473 ◽  
Author(s):  
Franziska Heidemann ◽  
Tilo Kölbel ◽  
E. Sebastian Debus ◽  
Holger Diener ◽  
Sebastian W. Carpenter ◽  
...  
Keyword(s):  
Renal Function ◽  
Renal Artery ◽  
Stent Graft ◽  
Aortic Surgery ◽  
Artery Occlusion ◽  
Aspiration Thrombectomy ◽  
Endovascular Revascularization ◽  
Renal Artery Occlusion ◽  
Local Lysis

Purpose: To analyze the renal function and outcome after delayed (>6 hours) endovascular revascularization of acute renal artery occlusion (RAO) in patients with fenestrated-branched endovascular aneurysm repairs (EVARs) or open visceral debranching. Methods: A single-center retrospective analysis was conducted involving 7 patients (mean age 61 years, range 49–72; 5 women) with 9 RAOs treated with endovascular revascularization between December 2014 and March 2017. Three patients had a solitary kidney with chronic renal insufficiency; 1 patient had bilateral occlusions as the acute event. Initial aortic surgery included 5 branched and 1 fenestrated EVAR as well as 1 open visceral debranching operation. Revascularization of the RAO was performed using aspiration thrombectomy, local lysis therapy, and stent-graft relining. The median time between initial aortic surgery and RAO was 10 months (range 0.5–17). Results: Median renal ischemic time to revascularization was 24 hours (range 7–168). Technical success was 100%, with 1 procedure-related access complication. Temporary dialysis dependency occurred in 4 patients. Mean in-hospital stay was 17 days (range 7–32) with 1 postoperative death at day 10 due to cardiac arrest of unknown cause. Mean follow-up was 10.3 months (range 1.5–27) in 5 of 6 discharged patients. During follow-up, 1 reintervention for recurrent occlusion was performed. At follow-up imaging, all renal arteries were patent. No permanent dialysis dependency occurred. Conclusion: Renal function can be salvaged by delayed revascularization for RAO with prolonged renal ischemia. The endovascular approach with aspiration thrombectomy, local lysis, and stent-graft relining is a feasible technique for revascularization after RAO in patients with fenestrated-branched EVAR or open visceral debranching.

A Large Animal Model for Acute Kidney Injury by Temporary Bilateral Renal Artery Occlusion

10.3791/62230 ◽  
2021 ◽  
Author(s):  
Ilias P. Doulamis ◽  
Alvise Guariento ◽  
Mossab Y. Saeed ◽  
Rio S. Nomoto ◽  
Thomas Duignan ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Animal Model ◽  
Renal Artery ◽  
Kidney Injury ◽  
Artery Occlusion ◽  
Large Animal Model ◽  
Large Animal ◽  
Renal Artery Occlusion ◽  
Bilateral Renal Artery

Characterization of the postocclusive response of renal blood flow in the cat

1978 ◽  
Vol 235 (4) ◽  
pp. F286-F290 ◽  
Author(s):  
W. S. Spielman ◽  
H. Osswald
Keyword(s):  
Blood Flow ◽  
Angiotensin Ii ◽  
Renal Artery ◽  
Renal Blood Flow ◽  
Artery Occlusion ◽  
Renal Nerves ◽  
Vasoconstrictor Response ◽  
Renal Artery Occlusion ◽  
Chronic Denervation

In contrast to the postocclusive hyperemia of brain, heart, and skeletal muscle, the hemodynamic response of the kidney following renal artery occlusion is highly variable in that both hyperemia and ischemia have been reported. The present study evaluates the factors influencing the renal response to complete renal artery occlusion (5-60 s) in the anesthetized cat. Marked postocclusive vasoconstriction could only be domonstrated in meclofenamate-treated (10 mg/kg) cats. The delta% renal blood flow (RBF) (30-s occlusion) was 16 +/- 4 in controls and 54 +/- 4 after meclofenamate (n= 10; P less than 0.001). Chronic denervation of the kidney, alpha-adrenergic receptor blockade, or infusion of [Sar1, Ile8]angiotensin II(2 microgram/min per kg) did not affect the postocclusive reduction of RBF, indicating that the vasoconstriction was independent of renal nerves, catecholamines, and circulating angiotesin II. Adenosine injected into the renal artery of five cats caused a dose-dependent transient fall of RBF. A dose of 100 nmol adenosine reduced RBF by 44 +/- 6% whereas after meclofenamate only 1 nmol produced the same degree of vasoconstriction. In summary, this study demonstrates a marked potentiation of the postocclusive vasoconstrictor response and the vasoconstrictive action of adenosine by meclofenamate in the anesthetized animal. No evidence was obtained to support a role for the sympathetic nervous system or circulating angiotensin II in mediating the postocclusive vasoconstriction.

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