Activation of spinal cord serotonergic neurons accompanies cold-induced sympathoexcitation

1994 ◽  
Vol 72 (8) ◽  
pp. 884-892 ◽  
Author(s):  
Alicia M. Passerin ◽  
William N. Henley
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Synthesis Inhibitor ◽  
Serotonergic Neurons ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
Hydroxyindoleacetic Acid ◽  
Dopa Accumulation ◽  
Sympathetic Nervous

These studies examined the hypothesis that serotonergic neurons located in central sites known to be involved with autonomic regulation are activated by cold exposure, a potent stimulator of the sympathetic nervous system. In all experiments, rats were exposed to either 3 °C or 22 °C for 24 h. Significant increases (p < 0.05) in urinary norepinephrine excretion, depletions of myocardial norepinephrine, and enhanced myocardial L-DOPA accumulation following decarboxylase inhibition provided evidence of sympathoexcitation at 3 °C. Accumulations of the serotonin metabolite 5-hydroxyindoleacetic acid, in saline-injected rats, and 5-hydroxytryptophan in decarboxylase-inhibited rats were increased in spinal cord and brainstem regions of cold-exposed rats. Two hours after injection of the serotonin synthesis inhibitor p-chlorophenylalanine, significantly greater depletions of serotonin in spinal cord and 5-hydroxyindoleacetic acid in spinal cord and brainstem of cold-exposed rats were noted; synthesis inhibition also caused a larger drop in body temperature in cold-exposed rats. Microdissections of raphe nuclei and thoracic spinal cord sites indicated that the principal sites of serotonergic activation were the dorsal and intermediate spinal regions, and the raphe magnus. Thus, cold-induced sympathoexcitation was accompanied by activation of serotonergic neurons in spinal cord and brainstem regions known to be involved in autonomic regulation.Key words: serotonin, cold, stress, sympathetic nervous system, spinal cord.

Activation of bulbospinal serotonergic neurons during cold exposure

1999 ◽  
Vol 77 (4) ◽  
pp. 250-258 ◽  
Author(s):  
Alicia M Passerin ◽  
Linda L Bellush ◽  
William N Henley
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Cold Exposure ◽  
Metabolic Response ◽  
Dark Cycle ◽  
Temporal Aspects ◽  
Hydroxyindoleacetic Acid ◽  
Sympathetic Nervous ◽  
Induced Changes

In a four-part study, we expand on our previous report that bulbospinal serotonin (5HT) neuronal activation occurs with 24 h of cold exposure. To characterize temporal aspects, rats were exposed to 3°C or were maintained at 22°C for 2, 8, 48, or 96 h (experiment 1) or for 15, 30, or 60 min (experiment 2). To ensure that cold-induced changes in 5HT activity were not due to disturbances in diurnal pattern, rats in experiment 3 were exposed to cold (8 h) during the dark cycle. To explore the hypothesis that cold-induced 5HT activation is part of a broad metabolic response that includes activation of the sympathetic nervous system, metabolically impaired (hypothyroid) rats were exposed to 8°C in experiment 4. Significant increments in 5-hydroxyindoleacetic acid (5HIAA) concentration were evident by 60 min of cold exposure and existed at all later time points measured. These findings were most robust in spinal cord and rostral brainstem. Activation in spinal cord was also found when rats were exposed to 8 h of cold during the dark cycle, the active period for rats. In experiment 4, hypothyroid rats exhibited significantly greater norepinephrine excretion compared with control rats exposed to the same cold stimulus; this finding was accompanied by significantly greater increments in 5HIAA concentration in rostral brainstem and spinal cord of hypothyroid rats. In addition, significant elevations in tryptophan concentration were noted throughout the brainstem and spinal cord of cold-exposed, hypothyroid rats relative to room temperature, hypothyroid rats. This finding suggested that elevations in 5HIAA concentration in these rats were due to increases in precursor availability. The implications of these findings relative to autonomic and metabolic control are discussed.Key words: serotonin, spinal cord, raphe, cold, sympathetic nervous system.

Role of the sympathetic nervous system in CCl4 hepatotoxicity

1960 ◽  
Vol 198 (3) ◽  
pp. 669-676 ◽  
Author(s):  
Deane N. Calvert ◽  
Theodore M. Brody
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Liver Mitochondria ◽  
Central Vein ◽  
Fat Depots ◽  
Sympathetic Nervous ◽  
Adrenergic Blocking ◽  
Stimulation Of

An hypothesis is proposed which states that the characteristic hepatic changes seen after the administration of carbon tetrachloride are the result of stimulation of central sympathetic areas which produce a massive discharge of the peripheral sympathetic nervous system. Stimulation of the sympathetic supply to the blood vessels of the liver results in restriction of blood flow in the liver, leading to anoxia and the characteristic necrosis around the central vein of the hepatic lobule. Similarly the discharge causes the release of unesterified fatty acids from the peripheral fat depots and the consequent deposition of lipid in the liver. This hypothesis is based upon experimental evidence using the following physiologic and pharmacologic maneuvers: adrenergic blocking agents, pretreatment with reserpine, adrenalectomy and section of the spinal cord—all are effective to a greater or lesser extent in preventing the changes characteristically seen in oxidative phosphorylation of the liver mitochondria, activation of a Mg-dependent ATPase and deposition of lipid in the liver. Transection of the spinal cord is the most effective treatment and prevents entirely the characteristic changes seen in the above-mentioned functions.

scholarly journals Age-Dependent Aggregation of α-Synuclein in the Nervous System of Gut-Brain Axis is Associated with Caspase-1 Activation

2021 ◽  
Author(s):  
Qi Hu ◽  
Mei Hong ◽  
Mengyang Huang ◽  
Quan Gong ◽  
Xiaofan Zhang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Dopamine Synthesis ◽  
Thoracic Spinal Cord ◽  
Caspase 1 ◽  
Thoracic Spinal ◽  
Age Dependent ◽  
Rate Limiting ◽  
Old Mice

Abstract α-Synuclein (α-Syn) plays a key role in the development of Parkinson’ desease (PD). As aging is acknowledged to be the greatest risk factor for PD, here we investigated α-Syn expression in the ileum, thoracic spinal cord, and midbrain of young (1-month-old), middle-aged (6-, 12-month-old) to old (18-month-old) mice. We demonstrated that both the levels of α-Syn monomers, oligomers and ratios of oligomers to monomers were increased with aging in the ileum, thoracic spinal cord, and midbrain. Whereas, the expression of tyrosine hydroxylase (TH), the rate-limiting enzyme for dopamine synthesis, was decreased with aging in the midbrain. We failed to find corresponding α-Syn mRNA increase with aging. However, we found an increased expression of caspase-1 in the ileum, thoracic spinal cord, and midbrain. A specific caspase-1 inhibitor VX765 significantly reduced levels of both the α-Syn monomers and oligomers triggered by the rotenone in vitro. Taken together, the increase in α-Syn aggregation with aging might not occur first in the gut, but simultaneously in the nervous system of gut-brain axis.. The mechanism of the age-dependent aggregation of α-Syn in nervous system is likely triggered by the aging-related caspase-1 activation.

scholarly journals Syringomyelia in demyelinating disease of the central nervous system: Report of two cases

2011 ◽  
Vol 139 (9-10) ◽  
pp. 657-660 ◽  
Author(s):  
Dejan Savic ◽  
Slobodan Vojinovic ◽  
Mirjana Spasic ◽  
Zoran Peric ◽  
Stevo Lukic
Keyword(s):  
Multiple Sclerosis ◽  
Spinal Cord ◽  
Central Nervous System ◽  
Nervous System ◽  
Magnetic Resonance ◽  
Demyelinating Disease ◽  
Clinical Signs ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
The Central Nervous System

Introduction. Syringomyelia is a cavitary extension inside the spinal cord which can be either symptomatic or congenitally-idiopathic. Syringomyelia during the course of the disease in patients presenting with clinically definite multiple sclerosis was described earlier. Syringomyelia in patients presenting with a clinically isolated syndrome suggestive of multiple sclerosis is unusual. Case Outline. We present two patients presenting with demy-elinating disease of the central nervous system with syringomyelia in the cervical and thoracic spinal cord. We did not find classical clinical signs of syringomyelia in our patients, but we disclosed syringomyelia incidentally during magnetic resonance exploration. Magnetic resonance exploration using the gadolinium contrast revealed the signs of active demyelinating lesions in the spinal cord in one patient but not in the other. Conclusion. Syringomyelia in demyelinating disease of the central nervous system opens the question whether it is a coincidental finding or a part of clinical features of the disease. Differentiation of the significance of syringomyelia finding in these patients plays a role in the choice of treatment concept in such patients.

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