Effect of stimulating right atrial receptors on renal blood flow

1982 ◽  
Vol 60 (12) ◽  
pp. 1672-1679 ◽  
Author(s):  
F. Karim ◽  
S. Kaufman ◽  
C. T. Kappagoda
Keyword(s):  
Blood Flow ◽  
Renal Mass ◽  
Carotid Sinus ◽  
Superior Vena ◽  
Renal Perfusion ◽  
Right Atrial ◽  
Myelinated Fibres ◽  
Right Atrial Appendage ◽  
The Right ◽  
Atrial Receptors

This investigation was undertaken to determine the effect of stretching the superior vena caval – right atrial (SVC–RA) junction and the right atrial appendage on blood flow to the kidney (RBF) and to establish whether any changes observed were influenced by the input from the baroreceptors in the carotid sinus. The experiments were performed on seven dogs, anaesthetized with α-chloralose. The systemic arterial (i.e., renal perfusion) pressure was held constant. At a carotid sinus pressure (CSP) of 59.0 ± 1.2 mmHg (1 mmHg = 133.322 Pa), the RBF increased from 218 ± 16.1 to 231.7 ± 18.4 mL/min per 100 g renal mass (p < 0.025). At a CSP of 88.0 ± 3.5 mmHg, the RBF increased from 230.1 ± 19.2 to 237.1 ± 19.2 mL/min per 100 g renal mass (p < 0.05). At a CSP of 137 ± 3.7 mmHg there were no significant changes in RBF. These responses were abolished by cutting (four dogs) or cooling the vagi (one dog only). In a subsidiary investigation it was shown that stretching the SVC–RA junction activated receptors in the endocardial surface of the right atrium which discharged into myelinated fibres in the vagi, having an average conduction velocity of 8.1 m/s (range 3.8–15). It is concluded that stimulation of right atrial receptors increases the RBF and that this response is influenced by the input from the barorceptors in the carotid sinus.

"Summation" of the increase in heart rate from stimulation of atrial receptors

1980 ◽  
Vol 58 (6) ◽  
pp. 666-672
Author(s):  
P. V. Greenwood ◽  
C. T. Kappagoda
Keyword(s):  
Heart Rate ◽  
Left Atrial ◽  
Superior Vena ◽  
Right Atrial ◽  
Propranolol Hydrochloride ◽  
Superior Vena Caval ◽  
The Right ◽  
Atrial Receptors ◽  
Stimulation Of ◽  
Wire Cage

In dogs anaesthetized with chloralose, application of stimuli which are likely to activate left atrial (L.A.) and right atrial (R.A.) receptors (complex unencapsulated endings) has been shown to result in an increase in heart rate. The present investigation was undertaken to determine whether the response elicited by the application of one stimulus (i.e., to the left atrium) could be enhanced by the application of a second stimulus (i.e., to the right atrium) in the same animal.The L.A. receptors were stimulated by distending a small balloon at the right upper pulmonary vein-L.A. junction and the R.A. receptors by "expanding" a spherical wire cage positioned at the superior vena caval (S.V.C.)-R.A. junction. Pressures in the S.V.C., R.A., L.A., and femoral artery were measured and the electrocardiogram monitored.In eight dogs stimulation of L.A. receptors resulted in an increase in heart rate (H.R.) of 18.5 beats/min (SEM 6.0; N = 23). In the same animals stimulation of R.A. receptors resulted in an increase in H.R. of 14.6 beats/min (SEM 2.0; N = 25). Application of both stimuli simultaneously resulted in an increase of 32.2 beats/min (SEM 8.0; N = 13). In four dogs propranolol hydrochloride (0.5 mg/kg) markedly diminished the response. In three dogs the response was abolished by bretylium tosylate (10 mg/kg).It is concluded that the increase in H.R. resulting from the application of these two stimuli could be "summated" and these findings support the proposition that the receptors in the two atria act as a functional entity.

Refractoriness of the Sheep Superior Vena Cava Myocardial Sleeve

2008 ◽  
Vol 233 (11) ◽  
pp. 1441-1447 ◽  
Author(s):  
Cuimei Zhao ◽  
Jie Qi ◽  
Xingyuan Liu ◽  
Huaizhi Chen ◽  
Jun Li ◽  
...  
Keyword(s):  
Superior Vena Cava ◽  
Superior Vena ◽  
Vena Cava ◽  
Ionic Current ◽  
Right Atrial ◽  
Parasympathetic Nerve ◽  
Right Atrial Appendage ◽  
The Right ◽  
Type 3

The cardiomyocytes in the superior vena cava (SVC) myocardial sleeve have distinct action potentials and ionic current profiles, but the refractoriness of these cells has not been reported. Using standard intracellular microelectrode techniques, we demonstrated in sheep that the effective refractory period (ERP) of the cardiomyocytes in the SVC (114.7 ± 6.5 ms) is shorter than that in the inferior vena cava (IVC) (166.7 ± 6.2 ms), right atrial free wall (RAFW) (201.0 ± 6.0 ms) and right atrial appendage (RAA) (203.1 ± 5.8 ms) ( P < 0.05). The right atrial cardiomyocyte ERP was heterogeneously shortened by acetylcholine, a muscarinic type 2 receptor (M2R) agonist. After perfusion with 15 μM acetylcholine, the shortest ERP occurred in the SVC (the ERP in the SVC, IVC, RAFW and RAA was 53.6 ± 2.7, 98.9 ± 2.2, 121.8 ± 6.0 and 109.7 ± 5.1 ms, respectively; P < 0.05). Carbachol (1 μM), another M2R agonist, produced a similar effect as acetylcholine. Furthermore, we used methoctramine, a M2R blocker, 4-DAMP, a muscarinic type 3 receptor (M3R) blocker, and tropicamide, a muscarinic type 4 receptor (M4R) blocker to inhibit the acetylcholine-induced ERP shortening of SVC cardiomyocytes, and found that the 50% inhibitory concentration for methoctramine, 4-DAMP and tropicamide was 5.91, 45.72 and 80.34 nM, respectively. Therefore, we conclude that the sheep SVC myocardial sleeve is a unique electrophysiological region of the right atrium with the shortest ERP both under physiological condition and under cholinergic agonist stimulation. M2R might play a major role in the response of the SVC myocardial sleeve to parasympathetic nerve tone. The association between the distinct refractoriness in SVC and atrial fibrillation originating from the region deserves further investigation.

Right atrial stretch decreases supraoptic neurosecretory activity and plasma vasopressin

1981 ◽  
Vol 241 (1) ◽  
pp. R44-R49
Author(s):  
R. P. Menninger
Keyword(s):  
Left Atrial ◽  
Supraoptic Nucleus ◽  
Right Atrial ◽  
Vasopressin Release ◽  
Plasma Vasopressin ◽  
Neurosecretory Neurons ◽  
Plasma Arginine ◽  
Right Atrial Appendage ◽  
The Right ◽  
Atrial Receptors

It is generally held that left atrial stretch (LAS) but not right atrial stretch (RAS) reflexly inhibits vasopressin release and results in a diuresis. To reexamine the influence of RAS on the release of vasopressin and on the behavior of antidromically identified supraoptic neurosecretory neurons, RAS and LAS were applied in pentobarbital-anesthetized cats. Weighted 20 or 30 g sutures were placed in the left atrium pulmonary vein junction and at the base of the right atrial appendage. Antidromically identified supraoptic nucleus neurons were inhibited by both RAS and LAS applied independently and together, although fewer neurons were responsive to RAS alone. Simultaneous stretch of both atria resulted in greater inhibition of these neurons than did stretch of either atrium alone. Stretch of the right atrium alone also resulted in a significant decrease in plasma arginine vasopressin measured by radioimmunoassay. Differences between these results and other reports may stem from differences in the method of RAS or the specific right atrial receptors affected.

Early Results of the Modified Right Atrial Lesion Set for the Cox-Cryomaze Procedure

2016 ◽  
Vol 11 (5) ◽  
pp. 342-348 ◽  
Author(s):  
Faisal Habib Cheema ◽  
Muhammad Amir Younus ◽  
Osama T. Siddiqui ◽  
Muhammad Jabran Younus ◽  
Muhammad Arif Mahmood ◽  
...  
Keyword(s):  
Superior Vena ◽  
Vena Cava ◽  
Right Atrial ◽  
Tricuspid Annulus ◽  
Lesion Pattern ◽  
Early Results ◽  
Right Atrial Appendage ◽  
The Right ◽  
Alternative Set

Objective The standard right atrial lesion (RAL) set, as originally outlined in the Cox-Maze III procedure, can be technically challenging when using a cryoprobe to create the lesions. We report our initial experience with an alternative set of RALs for the surgical treatment of atrial fibrillation (AF). Methods Between September 2011 and January 2015, a total of 112 patients underwent a CryoMaze procedure with biatrial lesions using argon-based cryoablation (cryoprobe temperature, −160°C). Although the standard left atrial lesion set was used, the RAL pattern was modified in this cohort of patients. The intracaval superior vena cava-inferior vena cava lesion was performed as in the pattern described for the standard Cox-Maze III procedure. In addition, a horizontal atriotomy incision (the “T” lesion) in the mid free wall of the right atrium was based roughly in the midintercaval line and extended medially as a linear cryolesion to the lateral tricuspid annulus at the so-called 2-o'clock position as in the Cox-Maze III lesion pattern. Ordinarily, a linear cryolesion would be placed from the tip of the right atrial appendage (RAA) to the anterior tricuspid annulus at the so-called 10-o'clock position to prevent macro re-entry around the base of the RA appendage. Our modification consisted of, instead, a linear cryolesion directed perpendicularly from the mid portion of the atriotomy (T lesion) to the tip of the RA appendage, which simply interrupted RAA re-entry at another point. Results The mean ± standard deviation age was 72.7 ± 10.6 years, 56.3% were males, and 63.1% had long-standing persistent AF. There were three operative deaths (2.6% with an observed over expected of 0.58), all in the concomitant procedures with associated cardiac disease. Overall follow-up was 91.3%. Freedom from AF at discharge, 1-, 3-, 6-, 12-, 24-month, and last follow-up [16.1 ±11.3 months (range, 0.4–43 months)], was 100%, 76.3%, 84.2%, 98.3%, 89.5%, 89.2%, and 90.5%, respectively. Similarly, freedom from antiarrhythmic drugs was 74% and 81%, whereas freedom from anticoagulants was 72% and 78% at 12 and 24 months, respectively. Conclusions These results suggest the modified RAL set to be an effective alternative to the traditional RALs of Cox-Maze III. By substituting this lateral RAA lesion for the more technically difficult medial lesion, the procedure becomes easier to perform and favorably impacts operative time while achieving comparable results in reducing AF burden.

scholarly journals Extremely late asymptomatic atrial lead dislodgement from the right atrial appendage to superior vena cava with autopsy findings

2020 ◽  
Vol 6 (10) ◽  
pp. 741-744
Author(s):  
Rena Nakamura ◽  
Yasuteru Yamauchi ◽  
Kaoru Okishige ◽  
Jiro Kumagai ◽  
Masahiko Goya ◽  
...  
Keyword(s):  
Superior Vena Cava ◽  
Superior Vena ◽  
Vena Cava ◽  
Atrial Appendage ◽  
Right Atrial ◽  
Autopsy Findings ◽  
Right Atrial Appendage ◽  
The Right ◽  
Lead Dislodgement

Influence of carotid sinus pressure on atrial receptors and renal blood flow

1982 ◽  
Vol 242 (2) ◽  
pp. H220-H226
Author(s):  
F. Karim ◽  
D. U. Mackay ◽  
C. T. Kappagoda
Keyword(s):  
Blood Flow ◽  
Renal Blood Flow ◽  
Left Atrial ◽  
Renal Mass ◽  
Carotid Sinus ◽  
Systemic Arterial Pressure ◽  
Left Pulmonary Vein ◽  
Atrial Receptors ◽  
Sinus Pressure ◽  
Stimulation Of

Stimulation of the atrial receptors results in an increase in renal blood flow. The present investigation was undertaken to determine whether this response was modulated by the input from the baroceptors in the carotid sinus. The experiments were performed on dogs anesthetized with chloralose. The systemic arterial pressure was held constant. The carotid sinuses were perfused at 62 +/- 1.3, 95 +/- 2.7, and 145 +/- 8.3 mmHg. The atrial receptors were stimulated by distension of small balloons positioned at the left pulmonary vein-atrial junctions and the left atrial appendage. At a carotid sinus pressure of 62 +/- 1.3 mmHg, the blood flow increased from 182 +/- 8.5 to 199 +/- 8.9 ml . min-1 . 100 g-1 renal mass. At a carotid sinus pressure of 95 +/- 2.7 mmHg, the blood flow increased from 202 +/- 9.6 to 209 +/- 10.4 ml . min-1 . 100 g-1 renal mass. At a carotid sinus pressure of 145 +/- 8.3 mmHg, the blood flow increased from 237 +/- 13.0 to 239 +/- 12.5 ml . min-1 . 100 g-1 renal mass. The first two responses alone were statistically significant. The response at a carotid sinus pressure of 62 +/- 1.3 mmHg was abolished by cutting or cooling the cervical vagi to 8--10 degrees C. It is concluded that stimulation of the left atrial receptors produces a reflex increase in blood flow to the kidney, and this response is modulated by the input from the carotid sinus baroceptors.

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