scholarly journals THE RESUSCITATION OF THE CENTRAL NERVOUS SYSTEM OF MAMMALS

1906 ◽  
Vol 8 (2) ◽  
pp. 289-321 ◽  
Author(s):  
G. N. Stewart ◽  
C. C. Guthrie ◽  
R. L. Burns ◽  
F. H. Pike

The cerebral circulation was interrupted for periods of three to eighty-one minutes by ligation of the innominate and left subclavian arteries proximal to the origin of the vertebral, in ninety-three cats. Eleven dogs were used in the earlier experiments. The eye reflexes disappear very quickly and a period of high blood pressure follows the occlusion immediately; vagus inhibition causes cardiac slowing and a fall in blood pressure, followed by a second rise after the vagus center succumbs to anaemia. Respiration stops temporarily (twenty to sixty seconds) after the beginning of occlusion, and then follows a series of strong gasps of the Cheyne-Stokes type, after which it stops until some time after the restoration of the cerebral circulation. The respiratory and vagus centers lose their power of functioning at approximately the same time. Asphyxial slowing of the heart may occur without the agency of the vagus center. The blood pressure slowly falls to a level which is maintained throughout the remainder of the period of occlusion. The anterior part of the cord and the encephalon lose all function; no reflexes are obtainable. The reflexes of the posterior part of the cord persist; the intravenous injection of strychnine does not affect the anterior part of the cord during the period of occlusion; but does affect the posterior portion of the cord. There is no secretion of tears or saliva, and the intra-ocular pressure is reduced. The blood pressure falls still more after release of the cerebra arteries, but soon begins to rise. The respiration returns suddenly, two to sixty minutes after restoration of the cerebral circulation, the first gasp being a strong one. The rate gradually increases until rapid enough for natural respiration. The eye reflexes and intra-ocular tension return more gradually, ten minutes to three hours after restoration of the cerebral circulation. The anterior part of the cord recovers its functions gradually. The first reflexes occur only on the same side as the stimulus, crossing of reflexes, to involve the other side, not occurring till later. As a rule, all reflexes return, and a short period of quiet follows. The anterior part of the cord again becomes irritable to strychnine, but succumbs to its action before the normal part. Spasms, of tonic, clonic, or mixed type, then appear, terminating in (a) death, (b) partial or (c) complete recovery. In partial recovery, disturbances of locomotion, such as walking in a circle, paralysis, dementia, loss of sight, hearing, and general intelligence, characterize the post-convulsive period. After complete recovery, there is a return to normal deportment. No gross lesions of the nervous system, other than a congested appearance of the previously anæmic area, were observed. Transection of the spinal cord stops the spasms below the level of section. Hemisection of the cord stops the spasms on the same side, below the level of section. Death, without any return of the reflexes after release of the cerebral arteries, has followed an occlusion of seven and one-half minutes. Respiration has returned after an occlusion of one hour. Five animals have recovered completely after an occlusion of seven minutes or more. Only one animal has recovered completely after an occlusion of fifteen minutes. No animal has recovered completely after an occlusion of twenty minutes. In Herzen's 26 resuscitation of an animal after several hours of cerebral anæmia, there must have been some anastomotic channels to the brain. Mayer's 27 limit of ten to fifteen minutes of cerebral anæmia, beyond which resuscitation is not practicable, is close to the correct one. It appears to us that, in cases of resuscitation two hours after cessation of the heart-beat, (Prus., loc.cit.) the auricles must have kept up a slow but, in some degree, an efficient movement of the blood through the brain. The truth of this suggestion might be tested by introducing some easily recognized, non-diffusible substance into a vein after the heart-beat ceases to affect a manometer, and later searching for it in the brain and other parts of the body. But, whatever the reason, cerebral anaemia in these cases must have been less complete than in our experiments. The histological alterations of the cord and brain are now being studied. The results will be published later.

1951 ◽  
Vol 97 (409) ◽  
pp. 792-800 ◽  
Author(s):  
L. Crome

The problems of the interdependence and unity of the brain and body have been put on a scientific basis by Pavlov and his successors. Bykov (1947) has, for example, been able to demonstrate that the cortex plays a leading part in the regulation of somatic processes, such as secretion of urine, blood pressure, peristalsis and metabolism. It is therefore reasonable to argue that lesions of the central nervous system will be reflected in the pathogenesis and course of morbid processes in the body. It does not follow, however, that this influence will necessarily be in the direction of greater lability, more rapid pathogenesis or more extensive destruction. The outstanding feature of the central nervous system is its plasticity and power of compensation. It is therefore possible and probable that those parts of the nervous system which remain intact will take over and compensate for the function of the lost ones. Emotion may, for example, lead to polyuria, but it does not follow that urinary secretion will be impaired in a leucotomized patient. The brain may well play an important part in the infective processes of a normal person, but the defence against infection in a microcephalic idiot may remain perfectly adequate, and may even be more effective than in a normal person, provided that the mechanism of the immunity and phagocytosis had been more fully mobilized in the course of his previous life.


2018 ◽  
Vol 25 (28) ◽  
pp. 3333-3352 ◽  
Author(s):  
Natalia Pessoa Rocha ◽  
Ana Cristina Simoes e Silva ◽  
Thiago Ruiz Rodrigues Prestes ◽  
Victor Feracin ◽  
Caroline Amaral Machado ◽  
...  

Background: The Renin-Angiotensin System (RAS) is a key regulator of cardiovascular and renal homeostasis, but also plays important roles in mediating physiological functions in the central nervous system (CNS). The effects of the RAS were classically described as mediated by angiotensin (Ang) II via angiotensin type 1 (AT1) receptors. However, another arm of the RAS formed by the angiotensin converting enzyme 2 (ACE2), Ang-(1-7) and the Mas receptor has been a matter of investigation due to its important physiological roles, usually counterbalancing the classical effects exerted by Ang II. Objective: We aim to provide an overview of effects elicited by the RAS, especially Ang-(1-7), in the brain. We also aim to discuss the therapeutic potential for neuropsychiatric disorders for the modulation of RAS. Method: We carried out an extensive literature search in PubMed central. Results: Within the brain, Ang-(1-7) contributes to the regulation of blood pressure by acting at regions that control cardiovascular functions. In contrast with Ang II, Ang-(1-7) improves baroreflex sensitivity and plays an inhibitory role in hypothalamic noradrenergic neurotransmission. Ang-(1-7) not only exerts effects related to blood pressure regulation, but also acts as a neuroprotective component of the RAS, for instance, by reducing cerebral infarct size, inflammation, oxidative stress and neuronal apoptosis. Conclusion: Pre-clinical evidence supports a relevant role for ACE2/Ang-(1-7)/Mas receptor axis in several neuropsychiatric conditions, including stress-related and mood disorders, cerebrovascular ischemic and hemorrhagic lesions and neurodegenerative diseases. However, very few data are available regarding the ACE2/Ang-(1-7)/Mas receptor axis in human CNS.


Parasitology ◽  
1941 ◽  
Vol 33 (4) ◽  
pp. 373-389 ◽  
Author(s):  
Gwendolen Rees

1. The structure of the proboscides of the larva of Dibothriorhynchus grossum (Rud.) is described. Each proboscis is provided with four sets of extrinsic muscles, and there is an anterior dorso-ventral muscle mass connected to all four proboscides.2. The musculature of the body and scolex is described.3. The nervous system consists of a brain, two lateral nerve cords, two outer and inner anterior nerves on each side, twenty-five pairs of bothridial nerves to each bothridium, four longitudinal bothridial nerves connecting these latter before their entry into the bothridia, four proboscis nerves arising from the brain, and a series of lateral nerves supplying the lateral regions of the body.4. The so-called ganglia contain no nerve cells, these are present only in the posterior median commissure which is therefore the nerve centre.


2021 ◽  
Vol 8 (29) ◽  
pp. 2639-2643
Author(s):  
Sruthy Unni ◽  
Ranju Sebastian ◽  
Elizabeth Joseph ◽  
Remani Kelan Kamalakshi ◽  
Jamsheena Muthira Parambath

BACKGROUND Anaesthesia for neurosurgery requires special considerations. The brain is enclosed in a rigid cranium, so the rise in intracranial pressure (ICP) which impairs cerebral perfusion pressure (CPP), results in irrepairable damage to various vital areas in the brain. Stable head position is required in long neurosurgical procedures. This is obtained with the use of clamps which fix the head rigidly. This is done usually under general anaesthesia because it produces intense painful stimuli leading to stimulation of sympathetic nervous system which in turn causes release of vasoconstrictive agents. This can impair perfusion in all organ systems. The increase in blood pressure due to sympathetic nervous system causes increase in blood flow. This causes increases in intracranial pressure which result in reduction in cerebral perfusion pressure once the auto regulatory limits are exceeded. We compared the effects of dexmedetomidine 1 µgm/kg and propofol 100 µgm/kg given as infusion over a period of 10 minutes before the induction of anaesthesia and continued till 5 minutes after pinning to attenuate the stress response while cranial pinning. In this study, we wanted to compare the effects of dexmedetomidine and propofol as infusion to attenuate the stress response while cranial pinning in patients undergoing neurosurgical procedures. METHODS This is a randomized interventional trial. Patients were divided into 2 groups of 20 each. Group 1 receiving dexmedetomidine and group 2 receiving propofol, both drugs given as infusion. Haemodynamic variables were monitored before and after cranial pinning. Data was analysed using IBM statistical package for social sciences (SPSS) statistics. The parameters recorded were analysed with the help of a statistician. RESULTS The two groups were comparable in demographic data. Incidence of tachycardia between group 1 and 2 showed that tachycardia to pinning was better controlled with propofol than dexmedetomidine (P < 0.05) which is statistically significant. There is no statistically significant difference in blood pressure values between group 1 and 2 after pinning. CONCLUSIONS From our study, we came to a conclusion that propofol was superior to dexmedetomidine in attenuating the heart rate response to cranial pinning. The effect of propofol and dexmedetomidine was comparable in attenuating the blood pressure response to cranial pinning. KEYWORDS Cranial Pinning, Dexmedetomidine, Propofol


2000 ◽  
Vol 279 (6) ◽  
pp. H2786-H2796 ◽  
Author(s):  
Shaohua Ye ◽  
Pantea Mozayeni ◽  
Michael Gamburd ◽  
Huiqin Zhong ◽  
Vito M. Campese

Increased sympathetic nervous system (SNS) activity plays a role in the genesis of hypertension in rats with chronic renal failure (CRF). The rise in central SNS activity is mitigated by increased local expression of neuronal nitric oxide synthase (NOS) mRNA and NO2/NO3 production. Because interleukin (IL)-1β may activate nitric oxide in the brain, we have tested the hypothesis that IL-1β may modulate the activity of the SNS via regulation of the local expression of neuronal NOS (nNOS) in the brain of CRF and control rats. To this end, we first found that administration of IL-1β in the lateral ventricle of control and CRF rats decreased blood pressure and norepinephrine (NE) secretion from the posterior hypothalamus (PH) and increased NOS mRNA expression. Second, we observed that an acute or chronic injection of an IL-1β-specific antibody in the lateral ventricle raised blood pressure and NE secretion from the PH and decreased NOS mRNA abundance in the PH of control and CRF rats. Finally, we measured the IL-1β mRNA abundance in the PH, locus coeruleus, and paraventricular nuclei of CRF and control rats by RT-PCR and found it to be greater in CRF rats than in control rats. In conclusion, these studies have shown that IL-1β modulates the activity of the SNS in the central nervous system and that this modulation is mediated by increased local expression of nNOS mRNA.


Author(s):  
Georgia E. Hodes

In the late 20th century, the discovery that the immune system and central nervous system were not autonomous revolutionized exploration of the mechanisms by which stress contributes to immune disorders and immune regulation contributes to mental illness. There is increasing evidence of stress as integrated across the brain and body. The immune system acts in concert with the peripheral nervous system to shape the brain’s perception of the environment. The brain in turn communicates with the endocrine and immune systems to guide their responses to that environment. Examining the groundwork of mechanisms governing communication between the body and brain will hopefully provide a better understanding of the ontogeny and symptomology of some mood disorders.


2021 ◽  
Vol 10 (2) ◽  
pp. 29-43
Author(s):  
Rohit Rastogi ◽  
Mamta Saxena ◽  
Devendra K. Chaturvedi ◽  
Mayank Gupta ◽  
Akshit Rajan Rastogi ◽  
...  

Our entire body, including the brain and nervous system, works with the help of various kinds of biological stuff which includes positively charged ions of elements like sodium, potassium, and calcium. The different body parts have different energy levels, and by measuring the energy level, we can also measure the fitness of an individual. Moreover, this energy and fitness are directly related to mental health and the signals being transmitted between the brain and other parts of the body. Various activities like walking, talking, eating, and thinking are performed with the help of these transmission signals. Another critical role played by them is that it helps in examining the mechanisms of cells present at various places in the human body and signaling the nervous system and brain if they are properly functioning or not. This manuscript is divided into two parts where, in the first part, it provides the introduction, background, and extensive literature survey on Kirlian experiments to measure the human's organ energy.


Author(s):  
J. Eric Ahlskog

Case example: Mrs. H. feels lightheaded intermittently during the day. This happens exclusively when she is up and about. Sometimes she notes graying of vision with these episodes. The feeling is not spinning (i.e., not vertigo). She has fainted twice when standing in line at the grocery store. If she sits, she feels much better. It is worse in the morning but may recur any time of the day. She feels fine while lying in bed at night. Older adults often worry about high blood pressure (BP), yet the opposite problem, low BP, is common among those with DLB or PDD. This is because the Lewy neurodegenerative process impairs the autonomic nervous system. The specific condition that may afflict those with DLB or PDD is orthostatic hypotension. The term orthostatic implies the upright position (i.e., standing); hypotension translates into low BP. Thus, the low BP occurring in these Lewy disorders develops in the upright position; conversely, it is normal or even high when lying down. When standing or walking, the BP may drop so low that fainting occurs. Among people with orthostatic hypotension, the BP is normal when sitting, although in severe cases, even the sitting BP is low. Whereas most people with DLB or PDD do not experience symptoms of orthostatic hypotension, it is sufficiently frequent to deserve attention. It often goes undiagnosed, even when fainting occurs. Unrecognized orthostatic hypotension may limit activities and impair the person’s quality of life. The first half of this chapter provides further background, with focus on BP measurement and recognition of orthostatic hypotension. The last half addresses treatment. The normal autonomic nervous system senses the position of our body with respect to the pull of gravity. It is able to reflexively counter gravity’s downward pull on the blood volume when standing (gravity tends to draw blood toward our feet when standing). An important mechanism for countering gravity’s pull is the constriction of blood vessel diameter in the lower half of the body. These vessels reflexively constrict during standing, in effect forcing blood up to the brain. The autonomic nervous system mediates these and other reflexive changes to stabilize BP.


Author(s):  
Michael Trimble

This chapter discusses the clinical necessity from which the intersection of neurology and psychiatry arose, exploring different eras and their associated intellectual milestones in order to understand the historical framework of contemporary neuropsychiatry. Identifying Hippocrates’ original acknowledgement of the relation of the human brain to epilepsy as a start point, the historical development of the field is traced. This encompasses Thomas Willis and his nascent descriptions of the limbic system, the philosophical and alchemical strides of the Enlightenment, and the motivations behind the Romantic era attempts to understand the brain. It then follows the growth of the field through the turn of the twentieth century, in spite of the prominence of psychoanalysis and the idea of the brainless mind, and finally the understanding of the ‘integrated action’ of the body and nervous system, which led to the integration of psychiatry and neurology, allowing for the first neuropsychiatric examinations of epilepsy.


2011 ◽  
pp. 141-148
Author(s):  
James R. Munis

Physiologist Claude Bernard lived in a time when very little was known about the mechanisms underlying physiologic findings, and he had ample access to clues garnered from observing machines. Let's consider homeostasis (a concept championed by Bernard), an example for which an engineered machine shed light on a fundamental principle of physiology. Homeostasis is simply the tendency of the body to maintain important physiologic variables (eg, heart rate, blood pressure, PACO2) at constant, preset values. An example is a simplified mechanical governor that could be used to regulate the rotational speed of a steam engine shaft. ‘Autoregulate’ might be a more apt word because the governor performs without external help or guidance, provided it is designed and built properly. It doesn't take much imagination to see an analogy between the mechanical governor and the autonomic nervous system. Both maintain specific variables at a constant set point through a process of feedback loops.


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