Showing papers on "Autonomic nervous system published in 1974"
TL;DR: The role of the sympathetic nervous system was delineated in the heart rate and pressor responses to sustained handgrip and it was concluded that the increase in resistance was the result of sympathetically induced vasoconstriction.
Abstract: Selective autonomic blockade with intravenous propranolol, practolol, atropine, and combined atropine-propranolol was utilized to elucidate the role of the autonomic nervous system in the hemodynamic responses in young adult male volunteers to handgrip sustained at 30% of maximal voluntary contraction for 3 min. The initial 30 s of the tachycardia response was found to be mediated by withdrawal of vagal dominance, as evidenced by blockade of this response by prior atropinization. The mid and late portion of the heart rate response curve was demonstrated to be sympathetic in origin, since it was unaffected by atropine, but was suppressed by combined atropine-propranolol blockade. Sympathetic stimulation appears to be a secondary mechanism for increasing the heart rate, however, as it becomes operative only after the first mechanism of vagal withdrawal has been utilized. This was confirmed by the finding that beta adrenergic receptor blockade alone had little effect on the heart rate response curve.
The pressor response to handgrip was accompanied by increased cardiac output and no change in calculated systemic vascular resistance. After propranolol, handgrip resulted in increased peripheral resistance and an equivalent rise in arterial pressure, but no increase in cardiac output. It was concluded that the increase in resistance was the result of sympathetically induced vasoconstriction. This response was shown to be independent of peripheral beta adrenergic receptor blockade by the use of practolol, a cardio-selective beta adrenergic receptor-blocking drug which caused identical hemodynamic responses to those observed after propranolol.
Left ventricular ejection time (corrected for heart rate) was prolonged by handgrip. The increased afterload imposed on the left ventricle by sustained handgrip may explain the prolongation of ejection time index. Preejection period was prolonged by SHG after propranolol and shortened after atropine. In addition to confirming the previously defined role of the parasympathetic nervous system, this study delineates the role of the sympathetic nervous system in the heart rate and pressor responses to sustained handgrip.
223 citations
TL;DR: The autonomic nervous system activity and mood ratings of 12 women were studied 6 days a week for a complete menstrual cycle and it was found that older women had higher basal body temperatures, less marked HR variability, and tended to have lower levels of SC, particularly in the luteal phase of the cycle.
Abstract: The autonomic nervous system activity and mood ratings of 12 women were studied 6 days a week for a complete menstrual cycle. The daily procedure consisted of a resting period, a series of 5 mild tones, time estimation (TE), and reaction time (RT) trials, and a final resting period. Significant increase in heart rate (HR), respiration rate, and body temperature, and a significant decrease in resting skin conductance (SC) were found during the luteal phase. During the ovulatory phase there were significant increases in autonomic responsivity, as shown by greater amplitude of SC response in the TE and RT situations as well as in faster SC drop-rate and greater HR variability. All of these autonomic variability measures coincided with a significant peak in feelings of elation and vigor.
Significant age effects were that older women had higher basal body temperatures, less marked HR variability, and tended to have lower levels of SC, particularly in the luteal phase of the cycle. The results are discussed in terms of the psychophysiological effects of estrogen and progesterone.
100 citations
TL;DR: The electron microscope observations indicated that neurons rather than glia are of major importance in facilitating virus spread within and from the nervous system.
Abstract: Summary
Three-week-old mice were inoculated with pseudorabies virus by means of the left hind foot pad. Infectious virus was isolated from tissues in the sequence: foot pad, sciatic nerve and dorsal root ganglion, lower, middle, upper spinal cord, and brain. Virus was recovered in one instance only from the liver, but could not be recovered from the spleen or heart blood. The involvement of the kidneys, adrenal glands, coeliac ganglion and skin in the spread of infection was also studied. The possible role of the autonomic nervous system in the pathogenesis is suggested. In this respect, immunosympathectomy prior to inoculation reduced the incidence of infection in the adrenal glands and kidneys. Interruption of the sciatic and femoral nerves led to reduced mortality and an altered pathogenesis. A new pattern of virus isolation from the tissues was observed in mice dying at later times following section or ligation of these nerves. The electron microscope observations indicated that neurons rather than glia are of major importance in facilitating virus spread within and from the nervous system.
84 citations
TL;DR: The purpose is to review the mechanism of this excessive irritability, focusing on autonomic nervous system control of the airways in patients with asthma of allergic origin as well as in patients in whom allergic causes cannot be found.
Abstract: Excessircb irritability of the airways is thr hallmark of asthma. It is conspicuous in patients with asthma of allergic origin as well as in patients in whom allergic causes cannot bc found. ?tI,v purpose is to review the mechanism of this excessive irritability, focusing cspc~c’ially up011 t,hc autonomic nervous system control of the airways. This paper is not int,cnclcd as an rxhaustivtl review of the sub.ject, but rathctr a summary oi’ present informut,ion and an indication of possible directions oE futurrb advances. Evidence has been accumulated that t.his mechanism could bc an ;~bnol*malit~ in each of thr major branches ot’ the autonomic nervous system, or, pcrhal)s more likclg, in the intcgratioii of 1111, control of bronchial smooth musc&lc, blood \-csscls, mu(aous glands, and othm target cells by cholinergic and adrcncqic neurons.
77 citations
TL;DR: It is suggested that the investigations presented are useful in the routine assessment of patients presenting with syncope and sinus bradycardia, and those patients with symptoms and poor autonomic responses may require pacing while those with physiological responses may need no treatment or may be helped by drugs.
Abstract: Twenty-four patients with sinus bradycardia and i6 control subjects were investigated using various autonomic reflex manoeuvres and drug response tests. Two groups ofpatients are suggested by the results: i) Bradycardia due to atrial disease (sinoatrial diseasel sick sinus) poor autonomic reponses, I6 patients. Of those with poor autonomic responses, 9 had additional AV conduction defects, and half had experienced Adams-Stokes syncope. 2) Bradycardia of physiological origin normal or supernormal autonomic responses. a) Those with normal autonomic function, 7 cases. The dominant atrial pacemaker in this group is possibly set at a lower rate than normal. Such patients were not found to be liable to Adams-Stokes syncope, but may have vasomotor syncope. b) Vagotonia, I case. On the basis of one patient it is suspected that sinus bradycardia may be due to 'vagotonia' or due to an unusual sensitivity of the atrium to vagal influence. All autonomic responses were supernormal. Such patients, though probably rare, may be especially liable to vasomotor syncope. It is suggested that the investigations presented are useful in the routine assessment of patients presenting with syncope and sinus bradycardia. Those patients with symptoms andpoor autonomic responses may require pacing while those with physiological responses may need no treatment or may be helped by drugs.
73 citations
TL;DR: Patients with mild hypertension thus show increased sympathetic drive to the heart and arterioles as well as decreased cardiac parasympathetic inhibition, and it is presumed that the increased plasma renin is also neurogenic.
Abstract: 1. Some of the haemodynamic abnormalities in mild (borderline) human hypertension appear to be neurogenic, since they can be completely abolished by pharmacological autonomic blockade. 2. The cardiac output is elevated in 30% of patients through increased sympathetic drive and decreased parasympathetic inhibition. 3. In the remainder, the higher blood pressure is maintained by increased total peripheral vascular resistance. 4. In approximately 30% of this latter group, the higher vascular resistance is maintained solely by increased alpha-adrenergic tone. 5. Elevated plasma renin activities in a proportion of cases are probably due to generalized increase in sympathetic nervous activity. 6. Patients with mild hypertension thus show increased sympathetic drive to the heart and arterioles as well as decreased cardiac parasympathetic inhibition. It is presumed that the increased plasma renin is also neurogenic. 7. Such a widespread distribution of altered autonomic tone suggests aberration of the function of the integrative centres of cardiovascular control. 8. Evidence is presented of a possible psychosomatic origin of these changes in some cases.
73 citations
TL;DR: As is well known, medical science remained stationary at best from Galen to the Renaissance, and even Vesalius, who in many points improved Galen's anatomical notions, left them unchanged as far as the so-called 'sixth nerve' was concerned.
Abstract: PREHISTORYt THE sTRucuREs which are known today as the peripheral vegetative nervous system were morphologically rather well known to Galen (A.D. 130-200), the greatest anatomist and physiologist of antiquity.\" His descriptions suggest that he gained his knowledge mostly from dissecting pigs. His so-called 'sixth cranial nerve' comprises what we call today the ninth (glossopharyngeal), tenth (vagus), eleventh (accessory) nerves and the sympathetic chain. He described the superior cervical ganglion, the inferior cervical ganglion, the semilunar ganglion and the rami communicantes. These anatomical notions are still to be found in the basic Traite des nerfs of Tissot in 1778.' Unfortunately Galen's physiological ideas are marred by his teleological zeal. He feels that these nerves are 'soft', because they come from the brain. Being soft they have to be purely sensory. He 'proves' then that they are there for this purpose anyhow. If by accident one of the nerves shows motor functions, it has in Galen's opinion dried up, and has become hard, and therefore motor. These nerves are hollow and make the so-called animal spirits go from one organ to the other, producing thus the phenomenon of 'sympathy'. Sympathy is an old and vague notion. In this case it accounts for the co-operation or co-ordination of organs, like irritation of the stomach producing syncope or convulsions by being transmitted via brain and nerves to the heart. Galen knew also a humoral kind of sympathy via bloodvessels, like for instance the relations of the pregnant uterus with the mammary glands.' As is well known, medical science remained stationary at best from Galen to the Renaissance. Even Vesalius, who in many points improved Galen's anatomical notions, left them unchanged as far as the so-called 'sixth nerve' was concerned. It is only his younger contemporary, the great Eustachius (1524-74), who in 1563 regarded the vagus and sympathetic as two different nerves. He described the sympathetic as the continuation of the abducens, our sixth cranial nerve.8 An important event in the
62 citations
TL;DR: Results obtained indicated there was a cardiac hyperfunction associated with increased NE metabolism in the incipient stage of hypertension of SHR, but relative ineffectiveness of β-blocker showed that cardiac hyper function was not the sole mechanism for the development of hypertension but rather an index of increased outflow of autonomic nervous system to the cardiovascular system as a whole.
Abstract: Results obtained in (1) and (2) indicated there was a cardiac hyperfunction associated with increased NE metabolism in the incipient stage of hypertension of SHR. However, relative ineffectiveness of β-blocker in arresting the development of hypertension (3) showed that cardiac hyperfunction was not the sole mechanism for the development of hypertension but rather an index of increased outflow of autonomic nervous system to the cardiovascular system as a whole. Enhancement of mesenchymal metabolism of vasculature, probably in response to the increased load to the vascular wall, was detectable even in the incipient stage of hypertension (4), and such a rapid mesenchymal response of vasculature, closely cooperating with the increased autonomic nervous outflow, seems to be important for the development and maintenance of hypertension in SHR.
61 citations
TL;DR: It appears that while a general autonomic nervous system arousal occurs during a spider phobic reaction, the demand characteristics of the phobic situation may greatly influence which physiological responses are most affected.
Abstract: Autonomic nervous system arousal should theoretically increase during a phobic reaction. Eleven spider phobics and 11 nonspider phobics viewed spider, seascape, and surgical slides while several physiological responses were continuously recorded. Results indicated that spider phobics showed significantly faster heart rate, greater heart rate variability, and vasoconstriction during spider slide presentations as compared to nonspider phobics. Spider phobics also showed more frequent phasic skin responses but not larger skin response amplitudes to spider slides. Respiration rate and respiration amplitude were not significantly different for the two groups. It appears that while a general autonomic nervous system arousal occurs during a spider phobic reaction, the demand characteristics of the phobic situation may greatly influence which physiological responses are most affected.
TL;DR: The behavior of the denervated heart in different stressful situations is considered and the presentation is limited to studies in which dogs have been chronically deprived of both sympathetic and parasympathetic nerves.
Abstract: • The performance of the heart in the intact subject is determined by the complex interplay of cardiac and extracardiac factors; the initial length of the myocardial fibers and the state of activity of the cardiac autonomic nerves are most important. The profound changes in cardiac behavior that attend excitation of the cardiac autonomic nerves have led to the concept of neurogenic dominance in the control of cardiac output, particularly in situations that strongly constrain the cardiovascular system. This concept is basic to an evaluation of the mechanisms by which the heart responds to changes in the peripheral circulation and has important implications in clinical cardiac transplantation. In this review, the behavior of the denervated heart in different stressful situations is considered; the presentation is limited to studies in which dogs have been chronically deprived of both sympathetic and parasympathetic nerves. The role of cardiac receptors and their afferent innervation has recently been reviewed and is not discussed in this paper (1, 2). TECHNIQUES OF CARDIAC DENERVATION
TL;DR: The neurobiological basis of psychopathology is surveyed with emphasis upon reciprocal balances between opposing ergotropic and trophotropic systems with their central nervous system, autonomic nervous system and neuroendocrine components.
Abstract: The neurobiological basis of psychopathology is surveyed with emphasis upon reciprocal balances between opposing ergotropic and trophotropic systems with their central nervous system (CNS), autonomic nervous system (ANS) and neuroendocrine components. The anatomical sites, neurophysiological interconnections, and neurochemical transmitters which subserve functions of arousal, attention, perception, motion, emotion, memory, and learning are outlined. Mechanisms whereby disorders of psychophysiologic, somatopsychic and classically organic type may be triggered through such neurobiological pathways are suggested.
TL;DR: It is shown that the autonomic transmitters can be released in the fetal heart and high doses of nicotine have an excitatory effect, probably due to the release of noradrenaline from either the sympathetic nerve or chromaffin tissue.
Abstract: Electrical stimulation of isolated fetal atria produced changes in the strength of contractions of the myocardium, attributable to the release of the autonomic transmitters, acetylcholine and noradrenaline. These contractile responses are blocked by tetrodotoxin, suggesting that the stimulation releases neurotransmitters from the developing autonomic nerve plexus within the heart. Atria from fetuses less than 13 weeks of gestation frequently did not respond to stimulation, and it is suggested that this is due to the immaturity of the autonomic nervous system at this stage. Nicotine did not have an inhibitory effect at any age, indicating that ganglionic receptors are not present in the fetal myocardium. High doses of nicotine have an excitatory effect, probably due to the release of noradrenaline from either the sympathetic nerve or chromaffin tissue. This study has shown that the autonomic transmitters can be released in the fetal heart. Other pharmacologic and histochemical evidence is discussed to determine whether autonomic transmission occurs in early gestation.
TL;DR: It is concluded that both divisions of the autonomic nervous system evoke motor responses and that the sympathetic motor effect is mediated via α-receptors.
Abstract: The effect of autonomic nerves and drugs on duct pressure and salivary flow was investigated in rat submaxillary gland. The results showed that it is possible to separate motor responses, probably exerted by activation of myoepithelial cells, from secretion. It is concluded that both divisions of the autonomic nervous system evoke motor responses and that the sympathetic motor effect is mediated via α-receptors.
TL;DR: A highly significant correlation between the excretion of sodium and potassium in the recumbent position and the retention of both ions in the upright position is found.
Abstract: The effect of upright posture as a physiological stimulus of the adrenergic nervous system was studied in 56 subjects with benign essential hypertension. The subjects received a controlled-sodium diet. Blood pressure, heart rate, catecholamines, plasma renin activity, and urinary creatinine, sodium, and potassium excretion were measured in the recumbent and upright positions. We found an alteration in the blood pressure response in subjects with benign essential hypertension; the postural increase in the mean blood pressure in normotensive subjects (3.18 ± 1.35 mm Hg) progressively disappeared and was replaced by a postural decrease in subjects with more severe stable hypertension (-6.71 ± 2.42 mm Hg). The hypertensive subjects also lacked the usual increase in urinary excretion of norepinephrine. A significant increase in plasma renin activity associated with a significant decrease in plasma norepinephrine occurred in subjects with labile hypertension with postural tachycardia. Finally, we found a highly significant correlation between the excretion of sodium and potassium in the recumbent position and the retention of both ions in the upright position.
TL;DR: This chapter highlights the norepinephrine (NE) synthesis and turnover in the brain and acceleration by physostigmine and shows that an active interrelationship exists between the two parts of the autonomic nervous system in the head.
01 Jan 1974
TL;DR: An important link between neurogenic and renal factors in the genesis of renal hypertension is probably to be found in the multiple actions of angiotensin on the peripheral autonomic nervous system.
Abstract: An important link between neurogenic and renal factors in the genesis of renal hypertension is probably to be found in the multiple actions of angiotensin on the peripheral autonomic nervous system. It is remarkable that discovery of these actions commenced only after 20 years of study of the well-known direct vasoconstrictor action of angiotensin. There was one exception, and this was the first clear demonstration that angiotensin has a direct action on the peripheral autonomic nervous system. In 1940, Braun-Menendez et al. provided convincing evidence in cross-transfusion experiments that angiotensin can cause adrenal medullary discharge. Release of adrenal catecholamines by angiotensin receives thorough treatment in Chapter 20. The subject was then to lie dormant until recent years when the action of angiotensin on the autonomic nervous system attracted the interest of many investigators and new information is now accruing rapidly. Unfortunately, it is still too early to assess whether or not these newly discovered actions of angiotensin play an important physiologic role in cardiovascular regulation.
TL;DR: In all patients with ALS the migration of macrophages into the inflammatory field was retarded, and in three patients the total number of cells was decreased, which could be due to a latent disorder of the autonomic nervous system.
Abstract: In ten patients with amyotrophic lateral sclerosis (ALS) and 146 control subjects, the cellular inflammatory response was studied by the "skin window" technique and 24 hours after inflicting the lesion. In all patients with ALS the migration of macrophages into the inflammatory field was retarded, and in three patients the total number of cells was decreased. This alteration could be due to a latent disorder of the autonomic nervous system.
TL;DR: It can be seen that the output and resistance are influenced by numerous factors and that many of these fatcors are regulated by two main homeostatic systems; the kidneys and the autonomic nervous systems.
Abstract: Blood pressure is a product of cardiac output and vascular resistance. In turn the cardiac output depends on the stroke volume and the heart rate. The vascular resistance, for all practical purposes, depends only on the diameter of the resistance vessels, whereas such factors as blood viscosity and length of the vascular system do not play a determinant role in human physiology. A simplified scheme of the very complex situation is given in Fig. 1. It can be seen that the output and resistance are influenced by numerous factors and that many of these fatcors are regulated by two main homeostatic systems; the kidneys and the autonomic nervous systems. These two systems are interrelated. Sympathetic innervation changes the renal blood flow and consequently the renal excretory function. The release of renin from kidneys is under strong sympathetic influence[1] and a specific blood flow independent β-receptor may be responsible for this [2] ? The renin-angiotensine system in turn controls the aldosterone secretion from adrenals so that both the kidneys and the autonomic nervous system relate to a hormone which is crucial for the sodium and water balance.
TL;DR: It is suggested that changes of gastrointestinal motility induced by stimulation of specific thermoreceptive substrates might contribute to the close relationship between temperature regulation and food intake.
Abstract: In dogs anaesthetized with sodium pentobarbital, gastric and duodenal motility were recorded with the balloon method, while the spinal cord was thermally stimulated during periods of 3–4 min duration. Arterial blood pressure, respiratory rate, and the temperatures of the rectum, spinal peridural space and foot pads were recorded simultaneously. Spinal cord cooling resulted in an increase in amplitudes and tonic level of the contraction waves, both in the stomach and in the duodenum, while spinal cord heating decreased amplitudes and tonic level. The changes of gastrointestinal motility evoked by spinal cord thermal stimulation are supposed to be mediated by the autonomic nervous system with an at least significant contribution of the sympathetic innervation of the alimentary canal. These findings suggest that changes of gastrointestinal motility induced by stimulation of specific thermoreceptive substrates might contribute to the close relationship between temperature regulation and food intake.
TL;DR: The results suggest that the decarboxylation products of l‐DOPA do not impair parasympathetic nerve activity but depress sympathetic nerve function predominantly by inhibiting both muscarinic and nicotinic sites of sympathetic ganglia.
Abstract: 1 The ability of intravenous L-DOPA to block sympathetic and parsympathetic nerves has been studied in cats and dogs pretreated with a monoamine oxidase inhibitor.2 L-DOPA inhibited positive chronotropic and pressor responses to dimethylphenylpiperazinium (DMPP) and McN-A-343 in dogs, and contractions of the nictitating membrane produced by these ganglion stimulants in cats.3 Responses of the cat nictitating membrane to preganglionic stimulation were inhibited by L-DOPA to a greater extent than those to postganglionic stimulation of the cervical sympathetic chain.4 In dogs, L-DOPA had no vagolytic action, but depressed vasoconstrictor responses elicited in the perfused hind-limb by electrical stimulation of the lumbar sympathetic chain.5 The degree of lumbar sympathetic chain inhibition correlated with the pressor response following L-DOPA, and both effects were prevented by prior decarboxylase inhibition.6 These results suggest that the decarboxylation products of L-DOPA do not impair parasympathetic nerve activity but depress sympathetic nerve function predominantly by inhibiting both muscarinic and nicotinic sites of sympathetic ganglia.
TL;DR: The blood flow of m.
Abstract: The blood flow of m. vastus lateralis, measured by the 133Xenon-clearance technique, was studied during exercise in healthy young males. Autonomic blockade of the heart caused a significant reduction of the blood flow of the working muscles compared with a control study.
TL;DR: It is suggested that in chronic complete heart block the sinoatrial node is under dominant sympathetic control and high resting idioventricular rates may be partly dependent on sympathetic drivd, but this does not appreciably influence resting id Gioventricular rate in the majority of cases.
Abstract: Autonomic blockade was produced in 9 patients with chronic complete heart block by the intravenous administration of atropine and propranolol. Atrial and ventricular rates after injection were compared with those before. In general, the atrial rate slowed and there was no significant change in ventricular rate. However, 2 patients with an initial ventricular rate of over 40 a minute showed significant slowing. It is suggested that in chronic complete heart block the sinoatrial node is under dominant sympathetic control. High resting idioventricular rates may be partly dependent on sympathetic drivd, but this does not appreciably influence resting idioventricular rate in the majority of cases.
TL;DR: An electronic model of a cardiac pacemaker cell is developed from a study of the Hodgkin—Huxley equations describing the dynamic behaviour of excitable tissue membranes, based on the functional hypothesis that the controlling factor is the leakage conductance of the membrane to sodium ions.
Abstract: An electronic model of a cardiac pacemaker cell is developed from a study of the Hodgkin—.Huxley equations describing the dynamic behaviour of excitable tissue membranes. The model is based on the functional hypothesis that the controlling factor is the leakage conductance of the membrane to sodium ions and that this is increased by stimulation of the sympathetic nerves and decreased by stimulation of the parasympathetic nerves. The resulting model shows close agreement with experimental results obtained by Levy and Ziesko on the heart of the anaesthetised dog. The model forms part of an circulatory-parameter analogue of the human circulatory system currently being constructed as an aid to studying the manner in which the parameters and control loops of this system adapt to prolonged periods of heavy exercise.