-
Progress in Brain Research 1977
Topics: Blood Pressure; Humans; Pressoreceptors
PubMed: 928755
DOI: 10.1016/S0079-6123(08)62710-7 -
Investigative Urology May 1975The influence of pressoreceptor stimulation on the micturition reflex and urethral pressure profile was studied. Stimulation of pressoreceptors of the aortic arch and...
The influence of pressoreceptor stimulation on the micturition reflex and urethral pressure profile was studied. Stimulation of pressoreceptors of the aortic arch and carotid sinus causes an increase of parasympathetic tone and a decrease of sympathetic tone. Striated muscular tone was also decreased. Pressoreceptor stimulation was simulated by electrical stimulation of the depressor nerve in the rabbit. Our studies show that with pressoreceptor stimulation micturition occurred with 24 per cent less bladder filling and 32 per cent less intravesical pressure than before stimulation, and urethral pressure profile showed a 17 per cent decrease of the maximum and mean urethral pressure. The interpretation of the action of parasympathicomimetic and sympathicomimetic drugs on bladder and bladder neck must take into consideration the cardiovascular effects of these drugs and therefore the effect on the pressoreceptors.
Topics: Animals; Electric Stimulation; Male; Parasympathetic Nervous System; Pressoreceptors; Pressure; Rabbits; Reflex; Sympathetic Nervous System; Urethra; Urinary Bladder; Urination
PubMed: 1120638
DOI: No ID Found -
Basic Research in Cardiology 1979In 9 mongrel dogs, venous return was completely drained from the caval veins to an oxygenator and returned to the femoral arteries with a roller pump. Perfusion rate of...
In 9 mongrel dogs, venous return was completely drained from the caval veins to an oxygenator and returned to the femoral arteries with a roller pump. Perfusion rate of systemic circulation and blood pressures in both caval veins were kept constant. Changes in the oxygenator weight were recorded and reflected reciprocal changes in integrated systemic venous blood volume. The vagal nerves were dissected. The carotid sinuses were separately perfused with blood by means of a pump. In 25 experiments, increases in carotid sinus pressure of 15 to 74 mm Hg resulted in decreases in systemic arterial pressure of 10 to 57 mm Hg and increases in systemic venous blood volume of 1.1 to 4.7 ml/kg. On an average, systemic venous blood volume was changed by 1.25 +/- 0.08 ml/kg when the change in systemic arterial pressure was 10 mm Hg. It is concluded that the carotid sinus pressoreceptor reflex considerably alters the systemic venous capacity which in tern alters venous return and cardiac output. These changes in cardiac output are expected to be small, but sufficient to alter the arterial pressure considerably. Thus, they might contribute nearly as much as the reflex effect on total peripheral resistance to the reflex control of arterial pressure.
Topics: Animals; Blood Pressure; Blood Volume; Cardiac Output; Carotid Sinus; Dogs; Pressoreceptors; Reflex; Venae Cavae
PubMed: 526254
DOI: 10.1007/BF01907641 -
The Anatomical Record Mar 1947
Topics: Blood Pressure; Blood Pressure Determination; Celiac Artery; Humans; Mesenteric Arteries; Mesenteric Artery, Superior; Nerve Endings; Pressoreceptors; Sensory Receptor Cells; Vasomotor System
PubMed: 20341968
DOI: No ID Found -
Neuroscience Research Oct 1991The effects of electrical stimulation of the posterior cerebellar vermis in anaesthetized, decerebrate and conscious animals are described, and include marked changes in... (Review)
Review
The effects of electrical stimulation of the posterior cerebellar vermis in anaesthetized, decerebrate and conscious animals are described, and include marked changes in blood pressure and heart rate and an inhibition of the baroreceptor reflex. These effects appear to be restricted to lobule IX, and can be duplicated by chemical stimulation, indicating that they are a genuine cerebellar phenomenon. The results of both neuroanatomical and neurophysiological experiments to investigate the pathways responsible for the effects are described, and these show there to be a direct projection of Purkinje cell axons to the parabrachial nucleus. Experiments designed to test a possible involvement of lobule IX in the alerting response have proved negative, and while lobule IX itself appears to have no role in conditioned cardiovascular responses, lesions of lobules VI and VII do result in a significant impairment of the acquisition of conditioned bradycardia in the rabbit.
Topics: Animals; Cardiovascular Physiological Phenomena; Cerebellum; Homeostasis; Pressoreceptors; Rabbits
PubMed: 1660994
DOI: 10.1016/0168-0102(91)90099-k -
Verhandlungen Der Deutschen... 1957
Topics: Action Potentials; Blood Physiological Phenomena; Blood Pressure; Blood Pressure Determination; Carotid Sinus; Pressoreceptors; Pressure
PubMed: 13530478
DOI: No ID Found -
Annals of the New York Academy of... Jun 2001Baroreceptors sense and signal the central nervous system of changes in arterial pressure through a series of sensory processes. An increase in arterial pressure causes... (Review)
Review
Baroreceptors sense and signal the central nervous system of changes in arterial pressure through a series of sensory processes. An increase in arterial pressure causes vascular distension and baroreceptor deformation, the magnitude of which depends on the mechanical viscoelastic properties of the vessel wall. Classic methods (e.g., isolated carotid sinus preparation) and new approaches, including studies of isolated baroreceptor neurons in culture, gene transfer using viral vectors, and genetically modified mice have been used to define the cellular and molecular mechanisms that determine baroreceptor sensitivity. Deformation depolarizes the nerve endings by opening a new class of mechanosensitive Ion channel. This depolarization triggers action potential discharge through opening of voltage-dependent sodium (Na+) and potassium (K+) channels at the "spike initiating zone" (SIZ) near the sensory terminals. The resulting baroreceptor activity and its sensitivity to changes in pressure are modulated through a variety of mechanisms that influence these sensory processes. Modulation of voltage-dependent Na+ and K+ channels and the Na+ pump at the SIZ by membrance potential, action potential discharge, and chemical autocrine and paracrine factors are important mechanisms contributing to changes in baroreceptor sensitivity during sustained increases in arterial pressure and in pathological states associated with endothelial dysfunction, oxidative stress, and platelet activation.
Topics: Animals; Blood Pressure; Cardiovascular Diseases; Neurons, Afferent; Pressoreceptors; Reference Values
PubMed: 11458669
DOI: 10.1111/j.1749-6632.2001.tb03662.x -
Clinical and Experimental Pharmacology... 19891. The arterial baroreceptors are reset to operate at higher pressure levels in hypertension. Rapid (acute) resetting occurs within the first few minutes after elevation... (Review)
Review
1. The arterial baroreceptors are reset to operate at higher pressure levels in hypertension. Rapid (acute) resetting occurs within the first few minutes after elevation of arterial pressure, but is only partial because the increased threshold for baroreceptor activation represents only 25-50% of the arterial pressure increase. 2. Complete resetting occurs when the increase in pressure threshold equals the increase in arterial pressure; in the rat this is present after 48 h hypertension. 3. The aortic calibre was studied in freely moving rats; the time taken for the diastolic calibre to reach maximum dilation correlated with the time taken for complete resetting of the threshold of the aortic baroreceptors. During transient pressure increases the displacement of the diastolic calibre was much greater than the increase in pulsation, indicating that, under physiological conditions, sustained distension of the diastolic calibre is an important factor in aortic baroreceptor distortion. 4. The relative change of the diastolic calibre, in relation to control calibre, remains relatively constant during transient pressure changes in aortae of increased calibre produced by chronic hypertension or growth. 5. It is concluded that complete resetting of the baroreceptors in hypertension occurs when the increased stress on the arterial wall is matched by a proportional increase in diastolic calibre.
Topics: Animals; Arteries; Humans; Hypertension; Pressoreceptors
PubMed: 2680187
DOI: 10.1111/j.1440-1681.1989.tb02992.x -
Urologia Internationalis 1979In a previous study, pressoreceptor stimulation was found to augment parasympathetic activity in the bladder. This investigation is a continuum to determine any...
In a previous study, pressoreceptor stimulation was found to augment parasympathetic activity in the bladder. This investigation is a continuum to determine any influence of similar effects on the ureter. With equal urine flow, stimulation of pressoreceptors caused an increase in ureteral peristaltic activity. The exact mechanism of action was not determined.
Topics: Animals; Electrophysiology; Male; Pressoreceptors; Rabbits; Ureter; Urodynamics
PubMed: 442285
DOI: 10.1159/000280260 -
Investigative Urology May 1977In a previous study (Bödeker, J., Vogt, W., Kölln, C.-P., and Nagel, R.: Invest. Urol., 12: 461, 1975.) pressoreceptor stimulation induced micturition at less than...
In a previous study (Bödeker, J., Vogt, W., Kölln, C.-P., and Nagel, R.: Invest. Urol., 12: 461, 1975.) pressoreceptor stimulation induced micturition at less than normal bladder filling. Furthermore, urethral pressure profile decreased in both maximal and mean values. In the present investigation the effects of pressoreceptor stimulation on bladder configuration, intravesical pressure, and vesicoureteral reflux were studied. With pressoreceptor stimulation, the bladder outlet became more funnel-shaped; the change in bladder configuration occurred without alteration in intravesical pressure; and vesicoureteral reflux could not be demonstrated.
Topics: Animals; Electric Stimulation; Male; Pressoreceptors; Pressure; Rabbits; Urethra; Urinary Bladder; Urination; Vesico-Ureteral Reflux
PubMed: 858661
DOI: No ID Found