Body Stimuli Research Articles

Neurotransmitters and second messenger systems in the carotid body.

It is well known that multiple cellular events are regulated by second messenger systems (Greengard and Costa, 1970; Sekar et al., 1986; Hockberger et al., 1987). Among second messengers, cAMP have been shown to modulate several ionic channels and neurotransmitter synthesis and release in different structures (Joh et al.,1978; Hockberger et al., 1987; Morita et al., 1987; Santiago et al., 1990). It has been reported that several stimuli of the carotid body (CB) like hypoxia, hypercapnic acidosis, high extracellular and cyanide, stimulate adenylate cyclase activity, and that hypoxia was the only one that induces cAMP increases in a calcium-free medium, this accumulation being proportional to the intensity of the hypoxic stimulation (Perez-Garcia et al., 1990). Therefore it was proposed a primary role for cAMP in CB chemotransduction (Perez-Garcia et al., 1990, 1991). It was further suggested that the specific activation of adenylate cyclase by hypoxia could reflect a direct effect of low pO2 on the cAMP biosynthetic machinery.

Arterial chemoreceptor influences on the laryngeal chemoreflex.

Prolonged apnea and cardiovascular changes have been elicited in infant animals by the application of water to the laryngeal mucosa. Previous reports have produced conflicting evidence in regard to the possible role of arterial chemoreceptors in modulating this reflex. The present study was designed to determine the effect of carotid body stimulation or suppression on the duration of apnea and severity of cardiovascular changes in response to water in the larynx of piglets. The role of swallowing in terminating the apnea was also investigated. Hypoxia and isoproterenol, both carotid body stimuli, caused decreased apnea duration. Hyperoxia was associated with prolonged apnea duration; however, dopamine, which inhibits carotid body chemoreceptors, produced no significant change. Hypotension and bradycardia were only observed after prolonged apnea or chemoreceptor stimulation, supporting the concept that the cardiovascular component of the laryngeal chemoreflex is a result of changes in blood gas concentration rather than a direct response to laryngeal chemostimulation. The interval between water application and initiation of swallowing was not significantly affected by hypoxia or carotid body stimulation and swallowing did not always occur before resumption of breathing.

Effects of doxapram on ionic currents recorded in isolated type I cells of the neonatal rat carotid body

Whole-cell patch-clamp recordings were used to investigate the effects of the respiratory stimulant doxapram on K + and Ca 2+ currents in isolated type I cells of the neonatal rat carotid body. Doxapram (1–100 μM) caused rapid, reversible and dose-dependent inhibitions of K + currents recorded in type I cells (IC 50 approximately 13 μM). Inhibition was voltage-dependent, in that the effects of doxapram were maximal at test potentials where a shoulder in the current-voltage relationship was maximal. These K + currents were composed of both Ca 2+-activated and Ca 2+-independent components. Using high [Mg 2+], low [Ca 2+] solutions to inhibit Ca 2+-activated K + currents, doxapram was also seen to directly inhibit Ca 2+-independent K + currents. This effect was voltage-independent and was less potent (IC 50 approximately 20 μM) than under control conditions. suggesting that doxapram was a more potent inhibitor of the Ca 2+-activated K + currents recorded under control conditions. Doxapram (10 μM) was without effect on L-type Ca 2+ channel currents recorded under conditions where K + channel activity was minimized and was also without significant effect on K + currents recorded in the neuronal cell line NG-108 15, suggesting a selective effect on carotid body type I cells. The effects of doxapram on type I cells show similarities to those of the physiological stimuli of the carotid body, suggesting that doxapram may share a similar mechanism of action in stimulating the intact organ.

The role of cyclic AMP in chemoreception in the rabbit caroid body

The present study identified physiological factors which influence the generation (and degradation) of cyclic AMP (cAMP) in the arterial chemoreceptor tissue of the mammalian carotid body. Experiments established a 3-way correlation between cAMP generation, neurotransmitter release from chemoreceptor cells, and carotid sinus nerve (CNS) activity. Incubation of carotid bodies in vitro for 10 min in media equilibrated with different low O 2 (‘hypoxic’) gas mixtures (5% O 2 or 10% O 2, balance N 2) elevated basal cAMP levels (100% O 2 media) in proportion to the stimulus intesity. Similar experiments using nodose sensory ganglia showed that low O 2 stimulation did not alter cAMP levels in this non-chemosensory tissue. However, the adenylate cyclase (AC) activator, forskolin (10 μM), evoked large increases in the cyclic nucleotide content in both carotid bodies and nodose ganglia. After chronic (10 days) CSN denervation or synpathectomy, the basal levels of cAMP in the carotid body were elevated; the cAMP response to low O 2 media (stimulus minus control) was increased after CSN denervation but remained unaltered after sympathectomy. The effects of zero Ca 2+ media on cAMP generation was examined in order to assess whether feedback from released neurotransmitters acting on known (presynaptic) type I cell receptors could have contributed to the observed changes in cAMP. Basal levels of cAMP were increased 2.8-fold, and the response to hypoxic stimulation was elevated 5-fold, in the absence of extracellular Ca 2+. Forskolin (10 μM) did not alter basal release of [ 3H]-catecholamines ([ 3H]CA: synthesized from [ 3H]tyrosine, or resting CSN discharge; however, stimulus-evoked [ 3H]CA release and CSN discharge were potentiated in the presence of forskolin. This increased release was primarily due to enhanced efflux of dopamine (DA). At increasing stimulus strengths, however, the relative effect of forskolin on [ 3H]CA release was diminished. The data suggest that the chemoreceptor type I cells in the carotid body generate cAMP in their transductive response to hypoxia, but that the net levels of cAMP in the tissue are also regulated by both feedback actions of released neurotransmitters and by the sympathetic and sensory innervation to the organ. The effects of forskolin on [ 3H]CA release and CSN activity, combined with the finding that hypoxia increases the cAMP content of the carotid body, suggest the immediate invlovement of this classical second messenger in chemotransduction and chemotransmission of natural carotid body stimuli.

Loss of information concerning hair displacement and other somatic stimuli in the first somatic sensory cortex of unanesthetized Macaca mulatta monkeys following dorsal funiculus transections

Metal microelectrodes were used to record extracellular potentials from single cells in the four cytoarchitectural areas 3a, 3b, 1 and 2 of the representation of the lower body of the postcentral gyrus of Macaca mulatta monkeys. The animals were paralyzed and artificially respirated while remaining awake. Non-noxious natural stimuli were employed to determine response characteristics, like the submodality, of cells. After recording from a series of normal animals, spinal cord lesions of the dorsal funiculus, were surgically performed at cervical or high thoracic spinal levels. The animals were allowed to recover, and the above-mentioned cell characterization procedures were performed. After the recording, animals were humanely sacrificed and histological reconstructions of the penetrations and the spinal lesions were made. In the postcentral gyrus of normal animals, cells in cytoarchitectural areas 3b and 1 responded predominantly to cutaneous stimuli while cells in areas 3a and 2 responded predominantly to deep stimuli. Responses to displacement of hairs were only recorded in the predominantly cutaneous areas. In these areas in animals with dorsal funiculus transections at cervical or high thoracic spinal cord levels, many fewer cells responded to somatosensory stimulation than in the same areas in normal animals. There were no longer any responses to hair displacement stimuli. In this lower body region, responses to cutaneous stimuli and responses to some deep stimuli were reduced. Cortical areas 3b and 1, that normally showed responses predominantly to cutaneous stimuli, had an increased percentage of responses to deep stimuli. Cells that did not respond to our somatic stimuli but that had a spontaneous firing pattern were found in the first somatic sensory cortex (SI). We conclude that at rostral spinal levels, the dorsal funiculus contains all of the information about hair displacement stimuli of the lower body that projects to the first somatic sensory cortex as well as much information from cutaneous receptors and some from deep receptors on the body surface. Temporal information as well as precise receptive field demarkation is also supplied to SI cells by the dorsal funiculus.

Past Running Experience as a Mediator of the Attentional Focus of Male and Female Recreational Runners

In 1988 research under our controlled laboratory conditions suggested that, when subjects are instructed to focus on bodily cues while running on a treadmill, females perceive the activity to be more strenuous than do males. It was reasoned that this difference might be due to differences in either self-monitoring style or past exercise experience of males and females. The purpose of the present study was to survey recreational runners to ascertain the types of cues/thoughts to which they attended during exercise. 115 male and 72 female undergraduate and graduate students at a major university completed an attentional focus questionnaire after a routine jogging session. Demographic information was also obtained regarding each subject's experience with running activities (e.g., frequency, intensity, past history, etc.). Analysis suggested that attentional focus during running was related more to running experience than to sex differences in self-monitoring style. Inexperienced subjects focused attention more on bodily stimuli associated with the activity while experienced subjects focused more on cues/thoughts unrelated to running (e.g., music, surrounding scenery, etc.). It was concluded that experienced recreational runners are more adept at diverting attention away from unpleasant bodily cues associated with exercise than are inexperienced runners.

Carotid bodies and expiratory muscle recruitment

\ e have reported previously (FASEB J 1989; 3:A401) that specific carotid body stimulation/inhibition tended to recruit/derecruit expiratory muscles in the same direction, and with similar time course, as the diaphragm in unanesthetized dogs (N = 5). One limitation of that study was the presence of pulmonary vagal afferent traffic that could have had an effect on expiratory muscle recruitment independent of the direct carotid body effects. To address this question, we blocked the pulmonary stretch receptor afferent traffic by bilateral cooling ofexteriorized (skin loops) cervical vagi in 3 awake, tracheotomized dogs. Excitatory (NaCN, 3-5 breaths N2) and inhibitory (dopamine, 3-5 breaths O ) stimuli of the carotid bodies during vagal blockade produced effects similar to those seen in nonblocked dogs; recruitment/derecruitment ofexpiratory musdes (triarigularis sterni, transversus abdominis) was in the same direction and had the same time course as changes in the crural diaphragm. We conclude that pulmonary stretch receptor afferents are not required for inspiratory or expiratory muscle recruitment/derecruitment in response to carotid body stimuli.

Carotid Bodies and Expiratory Muscle Recruitment

e have reported previously (FASEB J 1989; 3:A401) that specific carotid body stimulation/inhibition tended to recruit/derecruit expiratory muscles in the same direction, and with similar time course, as the diaphragm in unanesthetized dogs (N = 5). One limitation of that study was the presence of pulmonary vagal afferent traffic that could have had an effect on expiratory muscle recruitment independent of the direct carotid body effects. To address this question, we blocked the pulmonary stretch receptor afferent traffic by bilateral cooling ofexteriorized (skin loops) cervical vagi in 3 awake, tracheotomized dogs. Excitatory (NaCN, 3-5 breaths N2) and inhibitory (dopamine, 3-5 breaths O ) stimuli of the carotid bodies during vagal blockade produced effects similar to those seen in nonblocked dogs; recruitment/derecruitment ofexpiratory musdes (triarigularis sterni, transversus abdominis) was in the same direction and had the same time course as changes in the crural diaphragm. We conclude that pulmonary stretch receptor afferents are not required for inspiratory or expiratory muscle recruitment/derecruitment in response to carotid body stimuli.

Cognition and agoraphobia: Bias in the interpretation of threat

Foa and Kozak (1985, 1986) have proposed that agoraphobics are characterized by a fear structure in which information about physiological arousal is associated in memory with information about danger. Accordingly, agoraphobics should be more likely than normals to interpret ambiguous bodily stimuli as threatening. They are also expected to exaggerate the probability and cost of unpleasant events related to arousal more than of events unrelated to arousal. Three groups — untreated and treated agoraphobics, and normals — were administered three questionnaires designed to test these conjectures. Agoraphobics, but not normals, manifested the hypothesized cognitive biases. Moreover, these biases were greatly diminished in agoraphobics who had undergone cognitive-behavior therapy.

Body Image and the Process of Reconstructive Surgery

Newer craniofacial operative techniques produce rapid changes in objective appearance and permit the study of body-image change. In 21 patients with either Crouzon's disease or Alpert's syndrome, a four-factor model of body-image development was applied that emphasizes cognitive growth, perception of body stimuli, stimuli from the environment in the form of comparison, and the response from others. Before a child is of school age, he has substantially defined his body image, therefore corrective surgery must be considered earlier. Although surgical intervention may produce significant objective physical change, there is not a correspondingly rapid change in body image. Four phases in the modification of body image are (1) the decision to undergo surgery, (2) the operative experience, (3) the immediate postoperative period, and (4) the reintegration stage. Recognition of this phasic process will help integrate care of these patients.

Animal in Vivo Studies and In Vitro Experiments with Human Tubes for End-To-End Anastomotic Operation by a CO2-Laser Technique

A CO2-laser technique for reanastomosis was carried out in 4 groups of 10 rabbits testing different laser performances between 5 and 14 watts and different exposure times from .1-.5 seconds. Optimal energy density was found in Group 3 which was exposed to 64 watts/sq. cm. In this group 70% achieved successful reanastomosis i.e. an uncomplicated pregnancy with live-born young at term. With the laser technique only the serosa and subserosa are coagulated allowing the deeper tissue layers (muscularis and mucosa) to adapt without tension. Because there is no foreign body stimulus as there is with sutures tissue reaction is minimized. Not only is the laser microsurgery successful in reversing sterilization without additional techniques the complete operation in the animal experiments including the initial laparotomy required no more than 20 minutes lessening the danger of secondary infections and anesthetic risk.

Identical twins concordant for anorexia nervosa. A preliminary case report.

This case described the symptoms of anorexia nervosa occurring in identical twins. The problems of twinship, especially the failure to establish separate identities, complicated the more general psychological issues facing these adolescents in a disturbed family. In therapy the core issues of the anorexic patient persist--disturbance of body image, misinterpretation of body stimuli and a sense of ineffectiveness. Up to now therapy seems to have improved family function, making it easier for them to coexist and decreasing the feelings of hostility and negativism felt between the parents and the twins. Eating behaviour presently focuses on the twins' need to have equal amounts of food but less emphasis is placed on the food as an area of conflict for the family.

Frequency response of carotid body chemoreceptors in the cat to changes of PaCO2, PaO2, and pHa.

ArticleFrequency response of carotid body chemoreceptors in the cat to changes of PaCO2, PaO2, and pHa.J Ponte, and M J PurvesJ Ponte, and M J PurvesPublished Online:01 Nov 1974https://doi.org/10.1152/jappl.1974.37.5.635MoreSectionsPDF (3 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Back to Top Next Download PDF FiguresReferencesRelatedInformationCited ByO2 and CO2 Detection by the Carotid and Aortic BodiesTasting arterial blood: what do the carotid chemoreceptors sense?14 January 2015 | Frontiers in Physiology, Vol. 5Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body1 January 2012Sleep-induced breathing instability28 February 2013Sleep-induced breathing instability27 October 2011Control of breathing: Two types of delays studied in an integrated model of the respiratory systemRespiratory Physiology & Neurobiology, Vol. 170, No. 1Adequate stimuli of the carotid body: More than an oxygen sensor?Respiratory Physiology & Neurobiology, Vol. 157, No. 1The spatial relationship between type I glomus cells and arteriolar myocytes in the mouse carotid bodyAnnals of Anatomy - Anatomischer Anzeiger, Vol. 185, No. 6Neurocirculatory consequences of intermittent asphyxia in humansAiliang Xie, James B. Skatrud, David C. Crabtree, Dominic S. Puleo, Brian M. Goodman, and Barbara J. Morgan1 October 2000 | Journal of Applied Physiology, Vol. 89, No. 4Hebbian Covariance LearningEstimation of hypoxic ventilatory dynamics using pseudorandom inputsRespiration Physiology, Vol. 101, No. 3References and further readingElectrophysiological evidence for the reconstitution of chemosensory units in co-cultures of carotid body and nodose ganglion neuronsBrain Research, Vol. 534, No. 1-2Flow Detection by the Carotid BodyFlow-dependent chemosensory activity in the carotid body superfused in vitroBrain Research, Vol. 455, No. 1Origin of Respiratory Oscillations in Chemoreceptor DischargeNon-invasive technique for examining the respiratory proprioceptor system in manJournal of Biomedical Engineering, Vol. 9, No. 1References and further readingNeurophysiology of Breathing in Mammals1 January 2011Oscillation, Gating, and Memory in the Respiratory Control System1 January 2011Initiation and Control of Chemoreceptor Activity in the Carotid Body1 January 2011Reflex Responses to Chemoreceptor Stimulation1 January 2011Abnormalities in Respiratory Rhythm1 January 2011Effects of CO2 and H+ on the ventilatory response to peripheral chemoreceptors stimulationRespiration Physiology, Vol. 64, No. 1Arterial Chemoreceptors1 January 2011The Response Characteristic of Peripheral Chemoreceptors and Their Physiological RelevanceCarbon dioxide versus H ion as a chemoreceptor stimulusBrain Research, Vol. 245, No. 1The chemical control of respirationAnnals of Biomedical Engineering, Vol. 9, No. 5-6ASPECTS OF THE REGULATION OF RESPIRATION IN MUSCULAR EXERCISECHEMICAL BREATHING CONTROLS: SLOW, INTERMEDIATE AND FASTClinics in Chest Medicine, Vol. 1, No. 1Inspiratory-expiratory responses to alternate-breath oscillators of PACO2 and PAO2Respiration Physiology, Vol. 36, No. 3Pattern of the Ventilatory Response to Transient Hypoxia in Man: Differences from Transient Hypercapnic Test26 September 2008 | Archives Internationales de Physiologie et de Biochimie, Vol. 87, No. 2Further Studies on the Fluctuation of Chemoreceptor Discharge in the CatArterial Chemoreceptors More from this issue > Volume 37Issue 5November 1974Pages 635-47 https://doi.org/10.1152/jappl.1974.37.5.635PubMed4436187History Published online 1 November 1974 Published in print 1 November 1974 Metrics

Effect of body-image stimuli on verbal errors of dysphasic subjects.

given 20 sec. to name them. A Z score representing the difference between the proportion of neutral and bodystimuli errors for all Ss was 1.28 which was less than the critical value of 1.96 for significance, indicating there were no significant differences between proportion of neutral and body-stimuli errors. A Z score of 1.33 was calculated for the proportion of total errors for neutral and body stimuli for dysarthric and nondysarthric Ss and this was below the critical value of 1.96 indicating no significant differences. A Z score of 2.1 was calculated for the proportion of errors for neutral and body stimuli for Ss with mild and severe right-sided paralysis. The Z score was higher than the critical value of 1.96, indicating that body stimuli produced significantly more errors than neutral stimuli. The results suggest the naming of body parts is not necessarily affected by disturbed speech or language components but rather is affected by the physical impairment of the patient.

Body boundary and stimulus enhancement.

The relationship between body boundary and stimulus intensity was investigated by means of lifted weights. Ss with high Barrier scores were hypothesized to judge weights as heavier than those with lower scores. A disrupting variable was introduced into the task to test the second hypothesis that attention contributed to the heightened intensity of stimuli. The first hypothesis was supported. The second hypothesis was not supported as both groups were equally affected by the disrupting variable.

Effects of active movement on body-part size estimates.

Body-part size estimates of 20 male Ss were obtained under normal room illumination and under three basic conditions: active movement of a joint-bounded body part prior to making an estimate of that part, active movement of a different body part prior to making an estimate of joint-bounded and non-joint-bounded body parts as well as familiar non-body objects, and no movement prior to making an estimate of joint-bounded and non-joint-bounded body parts as well as non-body objects. The results did not support the hypotheses that induced muscular tension or increased attention to the estimating task creates an enhancing effect upon size judgments from pictorial memory of body or non-body stimuli. Other findings, such as overestimation of the head width and variability in estimation of the waist, were consistent with previous studies.

Oxygen consumption of the carotid body.

ARTICLESOxygen consumption of the carotid bodyFS FayFS FayPublished Online:01 Feb 1970https://doi.org/10.1152/ajplegacy.1970.218.2.518MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByPeripheral Chemoreceptors: Function and Plasticity of the Carotid Body1 January 2012Adequate stimuli of the carotid body: More than an oxygen sensor?Respiratory Physiology & Neurobiology, Vol. 157, No. 1Strain-associated differences in hypoxic chemosensitivity of the carotid body in ratsJ. V. Weil, T. Stevens, C. K. Pickett, K. Tatsumi, M. G. Dickinson, C. R. Jacoby, and D. M. Rodman1 May 1998 | American Journal of Physiology-Lung Cellular and Molecular Physiology, Vol. 274, No. 5Initiation and Control of Chemoreceptor Activity in the Carotid Body1 January 2011Mathematical analysis of tissue $$P_{O_2 }$$ distribution in the cat carotid bodyPfl�gers Archiv European Journal of Physiology, Vol. 407, No. 3Extracellular pH changes in the superfused cat carotid body during hypoxia and hypercapniaBrain Research, Vol. 342, No. 2Mathematical Analysis of PO2 and Local Flow Distribution in the Carotid BodyArterial Chemoreceptors1 January 2011THE PHYSIOLOGY OF CHEMORECEPTION IN THE CAROTID BODYRelationship between tissue pO2 and chemoreceptor activity of the carotid body in vitroBrain Research, Vol. 195, No. 1Oxygen usage of the cat carotid body perfused with cell-free solutionsIrish Journal of Medical Science, Vol. 148, No. 1Responses of the chemoreceptors of the cat carotid body perfused with cell-free solutionsIrish Journal of Medical Science, Vol. 148, No. 1Tissue PO2 in the Cat Carotid Body and Related FunctionsFactors Affecting O2 Consumption of the Cat Carotid BodyThe kinetics of local tissue $$P_{{\text{O}}_{\text{2}} } $$ decrease after perfusion stop within the carotid body of the cat in vivo and in vitroPfl�gers Archiv European Journal of Physiology, Vol. 369, No. 2Oxygen consumption of the isolated carotid body tissue (cat)Pflügers Archiv European Journal of Physiology, Vol. 366, No. 1Stimulus interaction in the responses of carotid body chemoreceptor single afferent fibersRespiration Physiology, Vol. 24, No. 3Stagnant asphyxia in the carotid body of the catRespiration Physiology, Vol. 12, No. 3Carotid body oxygen consumption of the catin vitroPfl�gers Archiv European Journal of Physiology, Vol. 323, No. 4 More from this issue > Volume 218Issue 2February 1970Pages 518-523 Copyright & PermissionsCopyright © 1970 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1970.218.2.518PubMed5412468History Published online 1 February 1970 Published in print 1 February 1970 Metrics

Estimation of distances on the body.

24 men and 24 women college students estimated the sizes of 13 body stimuli and 13 nonbody objects by adjusting markers on a horizontal rod and by drawing 1:4 scale pictures of their own bodies. Data were scores expressing response size as a percentage of stimulus size. In both response modes, percentage scores for body stimuli assumed a pattern that was not evident in estimates of nonbody-object sizes. Combinations of body parts, judged as a unit, were underestimated relative to estimates of component body parts judged separately. Ss' free drawings of the human figure, rated for disturbance in body image, were not significantly related to size-estimations of body or nonbody stimuli.