Endocrine system

2012 ◽  
Keyword(s):  
Nervous System ◽  
Autonomic Nervous System ◽  
Negative Feedback ◽  
Plasma Glucose ◽  
Hormone Secretion ◽  
Endocrine System ◽  
Pituitary Hormones ◽  
The Body ◽  
Autonomic Nervous ◽  
The Brain

Complex animals have evolved two separate systems for the control of body tissues. One is the nervous system, which makes direct connections with specific muscles and glands and regulates their activity by the focal release of neurotransmitters. The other system is the endocrine system, where hormones, secreted into the circulation, can exert effects on remote tissues in many different locations simultaneously. The classical distinction between the two systems is, however, blurred. Some hormones, such as antidiuretic hormone and oxytocin, are released into the bloodstream by neurones, rather than by typical endocrine cells. In other situations, hormones are released only to act locally, not all over the body, as with paracrine cells. Occasionally, the hormone feeds back on to the cell that secreted it, as in autocrine regulation. The interface between neural and endocrine control lies in the hypothalamus and related areas of the brain. This region also helps integrate the output of the autonomic nervous system, which controls visceral function. Hypothalamic areas also regulate appetite behaviours for food, water, sex, etc. Autonomic nervous system, appetites, and hormones all contribute to homeostasis — the regulation of the internal environment of the body. The hypothalamus and the pituitary gland form the ‘hypothalamic–pituitary endocrine axis’. This axis regulates much of the body’s endocrine activity through a system of hypothalamic factors. These factors, which are hormones in their own right, regulate the release of individual pituitary hormones. Each pituitary ‘trophic’ hormone then controls a part of the overall endocrine system. Thus, pituitary hormones control hormone production by thyroid, adrenal cortex, liver, and gonads. This complex cascade of hormonal control is regulated by various types of negative feedback based on plasma hormone concentrations. The hypothalamus and pituitary are also controlled by higher centres in the brain. Other endocrine tissues also use negative feedback control, but rather than the level of the hormone itself, it is the level of stimulus that regulates hormone secretion. Thus, rising plasma osmolarity (or decreasing blood volume) stimulates antidiuretic hormone secretion, and rising plasma glucose stimulates insulin secretion. Combinations of hormones are sometimes used to regulate an aspect of the internal environment. The control of plasma calcium by calcitonin, parathormone, and calcitriol (1,25-dihydroxycholecalciferol), and of plasma glucose by insulin and glucagon, are examples.

Principles of Neuroendocrinology and Hypothalamic Function

2021 ◽  
pp. 127-132
Author(s):  
Elizabeth A. Coon ◽  
Eduardo E. Benarroch
Keyword(s):  
Nervous System ◽  
Sexual Behavior ◽  
Autonomic Nervous System ◽  
Temperature Regulation ◽  
Emotional Responses ◽  
Endocrine System ◽  
Pituitary Hormones ◽  
Diurnal Rhythms ◽  
Autonomic Nervous ◽  
Hypothalamic Function

The hypothalamus is the neural center of the endocrine system, the regulator of the autonomic nervous system, and the circadian and seasonal clock for behavioral and sleep-wake functions. The hypothalamus maintains homeostasis by integrating cortical, limbic, and spinal inputs and by affecting hormone release, temperature regulation, intake of food and water, sexual behavior and reproduction, emotional responses, and diurnal rhythms. As the link from the nervous system to the endocrine system, the hypothalamus synthesizes and secretes neurohormones that stimulate or inhibit the secretion of pituitary hormones.

Neural integration of the hormonal contribution to homeostasis

1990 ◽  
Vol 7 (2) ◽  
pp. 154-158 ◽  
Author(s):  
CS Breathnach
Keyword(s):  
Nervous System ◽  
Autonomic Nervous System ◽  
Neural Control ◽  
Endocrine System ◽  
Pituitary Hormones ◽  
Endocrine Glands ◽  
Psychological Disturbances ◽  
Neural Integration ◽  
The Brain ◽  
Vast Area

AbstractApart from well known areas of overlap between endocrinology and psychiatry (e.g. studies, in psychiatric disorders, of neurohormones and of the response to manipulations of hypothalamic-pituitary-target gland axis, and analysis of behavioural and psychological disturbances in endocrinological disorders) there is a more intimate intrinsic relationship between the brain and the endocrine system which is less well known or studied. Many of the extracranial endocrine glands have autonomic innervation. Like the pituitary gland which is under direct neural (as well as humoral) diencephalic control, the extracranial endocrine glands are under direct neural control, integrated by the hypothalamus and “head ganglion of the autonomic nervous system”. Yet it is only in the case of the pancreatic islets that this integration has been clearly defined. It is postulated that by this innervation the somatic endocrine glands can respond to homeostatic needs with a rapid initial secretion before the more sustained outpouring of humoral agents typically regulated by blood-borne constituents including pituitary hormones. This is a vast area awaiting further investigation.

Emotional processing and the autonomic nervous system: a comprehensive meta-analytic investigation

2018 ◽  
Author(s):  
Pedro Silva Moreira ◽  
Pedro Chaves ◽  
Nuno Dias ◽  
Patrício Costa ◽  
Pedro Rocha Almeida
Keyword(s):  
Nervous System ◽  
Autonomic Nervous System ◽  
Skin Conductance ◽  
Emotional Processing ◽  
Skin Conductance Level ◽  
The Body ◽  
Analytic Investigation ◽  
Physiological Basis ◽  
Autonomic Nervous ◽  
Conductance Level

Background: The search for autonomic correlates of emotional processing has been a matter of interest for the scientific community with the goal of identifying the physiological basis of emotion. Despite an extensive state-of-the-art exploring the correlates of emotion, there is no absolute consensus regarding how the body processes an affective state.Objectives: In this work, we aimed to aggregate the literature of psychophysiological studies in the context of emotional induction. Methods: For this purpose, we conducted a systematic review of the literature and a meta-analytic investigation, comparing different measures from the electrodermal, cardiovascular, respiratory and facial systems across emotional categories/dimensions. Two-hundred and ninety-one studies met the inclusion criteria and were quantitatively pooled in random-effects meta-analytic modelling. Results: Heart rate and skin conductance level were the most reported psychophysiological measures. Overall, there was a negligible differentiation between emotional categories with respect to the pooled estimates. Of note, considerable amount of between-studies’ heterogeneity was found in the meta-analytic aggregation. Self-reported ratings of emotional arousal were found to be associated with specific autonomic-nervous system (ANS) indices, particularly with the variation of the skin conductance level. Conclusions: Despite this clear association, there is still a considerable amount of unexplained variability that raises the need for more fine-grained analysis to be implemented in future research in this field.

Vital staining of cells of the brain vegetative centers

1926 ◽  
Vol 22 (5-6) ◽  
pp. 730-731
Author(s):  
G. P.
Keyword(s):  
Nervous System ◽  
Autonomic Nervous System ◽  
Vital Staining ◽  
Frozen Sections ◽  
Autonomic Nervous ◽  
The Brain ◽  
Dark Blue

V. Rakhmanov (Zhurn. Neurop. And Psych., 1925, No. 3-4) proposes to inject them with 1% Trypanblau solution in the amount of 1 cubic meter to study the vegetative centers in mice. with. weekly for 6-8 weeks. The brain is fixed in 10% formalin, frozen sections are stained with alum carmine or cochineal. In this case, dark blue dust-like grains appear in the plasma and nuclei of cells - selectively for the cells of the autonomic nervous system.

DYNAMICS OF SERUM PROTEIN CONTENT AND PRODUCTIVITY OF CHICKENS WITH DIFFERENT TONUS OF THE AUTONOMIC NERVOUS SYSTEM

2021 ◽  
Vol 12 (4) ◽  
Author(s):  
A. A. Studenok ◽  
◽  
E .O. Shnurenko ◽  
V. O. Trokoz ◽  
V. I. Karposkyi ◽  
...  
Keyword(s):  
Nervous System ◽  
Body Weight ◽  
Autonomic Nervous System ◽  
Total Protein ◽  
Protein Metabolism ◽  
High Reliability ◽  
Negative Relationship ◽  
The Body ◽  
Main Role ◽  
Autonomic Nervous

The main role in maintaining the functioning of the body, its growth, and development belongs to protein. It is involved in the formation of the muscular skeleton and is s part of enzymes, neurotransmitters, hormones. The effect of the autonomic nervous system on total protein metabolism has not been sufficiently studied. It is known that the autonomic nervous system is a structure that is responsible for the homeostasis and stability of the whole organism. It participates in the regulation of the heart, endocrine and external secretion glands, gastrointestinal tract, excretory organs, and more. In our studies, it was found that in chickens of Cobb 500 strain with different tones of the autonomic nervous system during the growing period from the 35th to the 60th day, different contents of total protein, albumin, and globulins were observed and different body weights were recorded. Vagotonic chickens showed the lowest protein metabolism at the age of 35 and 45 days (P ˂ 0.05–0.001) compared with sympathicotonics and normotonics, which tended to increase between 35 and 60 days of rearing compared with other groups of birds, where the studied protein fractions on the contrary decreased. Correlations between total protein, albumin, and bird body weight had a high linear relationship in all groups of chickens (P ˂ 0.05–0.001) and a negative relationship between the 45th and 60th days of rearing in sympathicotonics and normotonics. In birds with a predominance of parasympathetic tone of the autonomic nervous system, this correlation maintained its direction with high reliability (P ˂ 0.05) between body weight and total protein on the 60th day of rearing.

Control of noradrenergic differentiation and Phox2a expression by MASH1 in the central and peripheral nervous system

Development ◽  
1998 ◽  
Vol 125 (4) ◽  
pp. 599-608 ◽  
Author(s):  
M.R. Hirsch ◽  
M.C. Tiveron ◽  
F. Guillemot ◽  
J.F. Brunet ◽  
C. Goridis
Keyword(s):  
Nervous System ◽  
Autonomic Nervous System ◽  
Peripheral Nervous System ◽  
Genetic Circuits ◽  
Autonomic Nervous ◽  
Peripheral Neurons ◽  
Dopamine Beta Hydroxylase ◽  
Targeted Mutation ◽  
The Brain ◽  
Noradrenergic Differentiation

Mash1, a mammalian homologue of the Drosophila proneural genes of the achaete-scute complex, is transiently expressed throughout the developing peripheral autonomic nervous system and in subsets of cells in the neural tube. In the mouse, targeted mutation of Mash1 has revealed a role in the development of parts of the autonomic nervous system and of olfactory neurons, but no discernible phenotype in the brain has been reported. Here, we show that the adrenergic and noradrenergic centres of the brain are missing in Mash1 mutant embryos, whereas most other brainstem nuclei are preserved. Indeed, the present data together with the previous results show that, except in cranial sensory ganglia, Mash1 function is essential for the development of all central and peripheral neurons that express noradrenergic traits transiently or permanently. In particular, we show that, in the absence of MASH1, these neurons fail to initiate expression of the noradrenaline biosynthetic enzyme dopamine beta-hydroxylase. We had previously shown that all these neurons normally express the homeodomain transcription factor Phox2a, a positive regulator of the dopamine beta-hydroxylase gene and that a subset of them depend on it for their survival. We now report that expression of Phox2a is abolished or massively altered in the Mash1−/− mutants, both in the noradrenergic centres of the brain and in peripheral autonomic ganglia. These results suggest that MASH1 controls noradrenergic differentiation at least in part by controlling expression of Phox2a and point to fundamental homologies in the genetic circuits that determine the noradrenergic phenotype in the central and peripheral nervous system.

Blood Pressure and Orthostatic Hypotension: Faints, Near-Faints, and Lightheadedness

2013 ◽  
Author(s):  
J. Eric Ahlskog
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Orthostatic Hypotension ◽  
Vessel Diameter ◽  
Upright Position ◽  
Grocery Store ◽  
The Body ◽  
Autonomic Nervous ◽  
Neurodegenerative Process

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.

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