scholarly journals Role of carotid chemoreceptors in control of breathing at rest and in exercise: Studies on human subjects with bilateral carotid body resection.

1985 ◽  
Vol 35 (4) ◽  
pp. 535-544 ◽  
Author(s):  
Yoshiyuki HONDA
Keyword(s):  
Carotid Body ◽  
Human Subjects ◽  
Control Of Breathing ◽  
Carotid Chemoreceptors ◽  
Bilateral Carotid

Important role of carotid afferents in control of breathing

1998 ◽  
Vol 85 (4) ◽  
pp. 1299-1306 ◽  
Author(s):  
L. G. Pan ◽  
H. V. Forster ◽  
P. Martino ◽  
P. J. Strecker ◽  
J. Beales ◽  
...  
Keyword(s):  
Control System ◽  
Carotid Artery ◽  
Carotid Body ◽  
Elevated Level ◽  
Treadmill Exercise ◽  
Important Determinant ◽  
Control Of Breathing ◽  
Ventilatory Control ◽  
Rest And Exercise

The purpose of the present study was to determine the effect on breathing in the awake state of carotid body denervation (CBD) over 1–2 wk after denervation. Studies were completed on adult goats repeatedly before and 1) for 15 days after bilateral CBD ( n = 8), 2) for 7 days after unilateral CBD ( n = 5), and 3) for 15 days after sham CBD ( n = 3). Absence of ventilatory stimulation when NaCN was injected directly into a common carotid artery confirmed CBD. There was a significant ( P < 0.01) hypoventilation during the breathing of room air after unilateral and bilateral CBD. The maximum [Formula: see text] increase (8 Torr for unilateral and 11 Torr for bilateral) occurred ∼4 days after CBD. This maximum was transient because by 7 (unilateral) to 15 (bilateral) days after CBD, [Formula: see text]was only 3–4 Torr above control. CO2 sensitivity was attenuated from control by 60% on day 4 after bilateral CBD and by 35% on day 4after unilateral CBD. This attenuation was transient, because CO2 sensitivity returned to control temporally similar to the return of[Formula: see text] during the breathing of room air. During mild and moderate treadmill exercise 1–8 days after bilateral CBD, [Formula: see text] was unchanged from its elevated level at rest, but, 10–15 days after CBD,[Formula: see text] decreased slightly from rest during exercise. These data indicate that 1) carotid afferents are an important determinant of rest and exercise breathing and ventilatory CO2 sensitivity, and 2) apparent plasticity within the ventilatory control system eventually provides compensation for chronic loss of these afferents.

Do Carotid Chemoreceptors Inhibit the Hyperventilatory Response to Heavy Exercise?

1994 ◽  
Vol 19 (3) ◽  
pp. 350-359 ◽  
Author(s):  
Jerome A. Dempsey ◽  
Curtis A. Smith
Keyword(s):  
Tidal Volume ◽  
Key Words ◽  
Carotid Body ◽  
Motor Output ◽  
Heavy Exercise ◽  
Feed Forward ◽  
Carotid Chemoreceptors ◽  
Carotid Body Denervation

In this paper two types of evidence are presented which question the commonly presumed role of carotid chemoreceptor stimulation as the primary mediator of the hyperventilatory response to heavy exercise. First, carotid-body denervation in ponies increases their hyperventilatory response to heavy exercise. Second, the awake dog and the goat at rest show an immediate and substantial depression of tidal volume and of ventilation when their isolated carotid chemoreceptors are made hypocapnic. Accordingly, it is proposed that during heavy exercise the carotid chemoreceptors are inhibitory to respiratory motor output and that the cause of the hyperventilatory response originates from extrachemoreceptor, locomotor-linked, feed-forward stimuli. Key words: hypocapnic inhibition, medullary chemoreceptors, locomotor-linked stimuli, feed-forward

Dynamic ventilatory responses to CO2 in the awake lamb: role of the carotid chemoreceptors

1991 ◽  
Vol 71 (6) ◽  
pp. 2198-2205 ◽  
Author(s):  
J. L. Carroll ◽  
E. Canet ◽  
M. A. Bureau
Keyword(s):  
Time Delay ◽  
Carotid Body ◽  
Time Course ◽  
Step Change ◽  
Co2 Response ◽  
Carotid Chemoreceptors ◽  
Ventilatory Responses ◽  
Central Chemoreceptors ◽  
Volume Response

In awake lambs we investigated the role of the peripheral chemoreceptors in producing dynamic ventilatory (VE) responses to CO2. The immediate VE response, within 15 s, to transient CO2 inhalation was studied in two groups: 1) five lambs before carotid denervation and 2) the same lambs after carotid denervation. The time course of VE responses during the first 60 s after a step change to 8% inspired CO2 was also studied in lambs after carotid denervation and in a group of six carotid body-intact lambs 10–11 days of age. Acute CO2 responses were assessed using step changes to various concentrations of CO2 + air and CO2 + O2, while VE was recorded breath by breath. Intact lambs exhibited a brisk VE response to step changes in CO2, beginning after 3–5 s. Hyperoxia altered but did not suppress the dynamic VE CO2 response when the carotid chemoreceptors were intact. Carotid denervation markedly reduced the VE response during the first 25 s after a CO2 step change, revealing the time delay required for the central chemoreceptors to produce an effective VE response. The residual VE response remaining after CD was thought to be mediated by the remaining aortic body chemoreceptors and was eliminated by adding O2 to the CO2 challenges. However, after carotid denervation, even with CO2 + hyperoxia, the onset of a small tidal volume response was apparent by 10–12 s.(ABSTRACT TRUNCATED AT 250 WORDS)

Carotid chemoreceptors influence arterial pressure in intact and aortic-denervated rats

1992 ◽  
Vol 262 (4) ◽  
pp. R677-R683 ◽  
Author(s):  
K. G. Franchini ◽  
E. M. Krieger
Keyword(s):  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Carotid Body ◽  
Hypotensive Effect ◽  
Carotid Chemoreceptors ◽  
Arterial Pressure Variability ◽  
Before And After ◽  
The Mean

The objective of the present study was to analyze the role of the arterial chemoreceptors in arterial pressure alterations produced by sinoaortic denervation (SAD) in rats. The mean arterial pressure during 2 h of continuous computerized beat-to-beat recordings was higher after aortic denervation (AD; 130 +/- 2 and 124 +/- 3 mmHg, respectively), lower after sinus denervation (SD; 101 +/- 1 and 101 +/- 3 mmHg), and remained unaltered after SAD (121 +/- 3 and 108 +/- 2 mmHg) 1 and 20 days after denervation compared with control rats (114 +/- 1 mmHg). Hypotensive effect of SD was confirmed when arterial pressure was recorded in the same animal before and after SD (from 112 +/- 2 to 103 +/- 2 mmHg). A similar effect was observed after isolated carotid body artery (CBA) ligation (from 114 +/- 3 to 104 +/- 3 mmHg). Furthermore, CBA ligation attenuated by 13% the hypertension after AD (from 136 +/- 2 to 118 +/- 3 mmHg). Bradycardic response to phenylephrine and arterial pressure variability were markedly altered by SAD and AD but remained normal after SD. In contrast, the chemoreflex (intravenous KCN) was abolished after SAD, SD, and CBA ligation but was preserved after AD. These data suggest that the arterial pressure alteration produced by SAD in rats represents the net effect of the abolition of inhibitory (baroreceptor deafferentation) and excitatory (chemoreceptor deafferentation) influences on the arterial pressure.

The Role of Saline Aerosols in the Prevention and Therapy of Cardio-respiratory and Osteo-muscular Afflictions

2018 ◽  
Vol 69 (10) ◽  
pp. 2826-2832
Author(s):  
Ioan Gabriel Sandu ◽  
Viorica Vasilache ◽  
Andrei Victor Sandu ◽  
Marin Chirazi ◽  
Cezar Honceriu ◽  
...  
Keyword(s):  
Athletic Performance ◽  
Gaseous Medium ◽  
Human Subjects ◽  
Active Surface ◽  
Positive Influence ◽  
Climatic Parameters ◽  
Gaussian Distributions ◽  
Gaseous Media ◽  
Source Number

The saline aerosols generated in gaseous media, as nanodispersions, behave, with respect to the concentration levels and the lifespan, as trimodal distributions (the three domains with Gaussian distributions: fine or Aitken under 50 �m, medium between 50 and 500 mm and, respectively, coarse or large between 500 and 1000 mm). The generation in latent state is dependent on the active surface of the source (number of generator centres, the size and position of the fluorescences, the porosity, size and shape of the source, etc.), the climatic parameters, but also on a series of other characteristics of the gaseous medium. Our team has demonstrated experimentally that saline aerosols, NaCl type, besides the ability to prevent and treat broncho-respiratory and cardiac conditions, through coassistance of saline aerosols of other cations than sodium, and of the iodine anion, have for certain levels of concentrations propitious effects over the immune, bone and muscular systems. Similarly proved has been the positive influence on the development of children, as well the determinant role in increasing athletic performance and of other human subjects performing intense activities.

Monosodium Glutamate Toxicity and the Possible Protective Role of L–Carnitine

2018 ◽  
Vol 6 (1) ◽  
pp. 45-56
Author(s):  
Lalrinzuali Sailo ◽  
◽  
Meesala Krishna Murthy ◽  
Khandayataray Pratima ◽  
Vikas Kumar Roy ◽  
...  
Keyword(s):  
Human Subjects ◽  
Monosodium Glutamate ◽  
Essential Amino Acids ◽  
Protective Role ◽  
Glutamate Toxicity ◽  
Common Salt ◽  
Genotoxic Effects ◽  
Naturally Occurring ◽  
Flavour Enhancer

Monosodium glutamate is naturally available non-essential amino acids, which found in naturally occurring foods and used as flavour enhancer worldwide. Monosodium glutamate is believed to be linked with diverse health problems. The aim of the study was toxic effects of monosodium glutamate (MSG) and the protective role of L-carnitine, light on the available literature from last 25 years about diverse toxicity studies which had been carried out on animal and human models. Google scholar, NCBI, PUBMED, EMBASE, Wangfang databases, and Web of Science databases were used to retrieve the available studies. MSG was linked with deleterious effects particularly in animals including induction of obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects showed in Literature. Few reports revealed increased hunger, food intake, and obesity in human subjects due to MSG consumption. Hepatotoxic, neurotoxic, and genotoxic effects of monosodium glutamate on humans carried out very limitedly. High consumption of monosodium glutamate may be linked with harmful health effects showed in available literatures. So, it is recommended to use common salt instead of MSG. Furthermore, intensive research is required to explore monosodium glutamate–related molecular and metabolic mechanisms. L-carnitine can protect from Hepatotoxic, neurotoxic, renal impairment and genotoxic effects functionally, biochemically and histopathologically with a corresponding reduction of oxidative stress.

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