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1
Content available remote

New insights into physiology and pathophysiology by resistance-volume recordings

100%
Ulmer W. T., Schafer T.
Journal of Physiology and Pharmacology. Supplement
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2004
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tom 55
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nr 3
149-153
This work deals with the assessment of airway resistance in the course of a single breath. The study showed the presence of an early increase in the resistance at the beginning of expiration, which intensifies during expiration and ends up with a sharp decline during expiring the last remaining volume of ca 350 ml. The dynamic changes in airway resistance over a breath depend on the disharmonic interplay between diaphragm function and bronchial wall tonus. Thus, airway resistance is not constant during breathing, as could be misleadingly judged from the total resistance averaged over a breath. The study underscores the importance of recording the resistance-volume curves alongside the standard flow-volume curves to be able to discern the peculiarities of airway resistance changes during a single breath. Knowing changes in the instantaneous airway resistance characteristic for a given lung pathology could appreciably improve the diagnostic and therapeutic powers.
2
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Hypoxic ventilatory profile in the anesthetized rat

100%
Marczak M., Kolesnikova E. E., Pokorski M.
Journal of Physiology and Pharmacology. Supplement
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2004
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tom 55
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nr 3
89-94
In the present study we investigated whether hypocapnia that accompanies hypoxic hyperventilation might affect the biphasic, stimulatory/depressant, ventilatory response to hypoxia. The experiments were carried out in anesthetized, vagotomized, spontaneously breathing, and poikilocapnic rats. The animals were subjected to acute steady-state hypoxia consisting of 12% O2 in N2 in inspiratory mixture. Ventilation and its frequency and volume components were assessed from the integrated electromyographic activity of the diaphragm. We found that despite the development of significant hypocapnia, the hypoxic ventilatory response consisted of rapid stimulation followed by a gradual decline. The frequency component contributed more to the ventilatory increase than that of volume. The results indicate that the hypoxic ventilatory profile in the anesthetized poikilocapnic rat resembles that known to be present during isocapnia. We conclude that hypocapnia neither hampers the hypoxic ventilatory reactivity nor alters the biphasic hypoxic ventilatory profile. These observations may aid planning experimental rat model studies.
3
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Respiratory responses to voluntary and reflexly-induced stepping movements in normal subjects and spinal patients

100%
Isaev G. G., Gerasimenko Y. P., Selionov V. A., Kartashova N. A.
Journal of Physiology and Pharmacology. Supplement
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2004
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tom 55
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nr 3
77-82
In the present study, the mechanisms of interaction between the breathing and stepping movements were investigated. The investigations were carried out in 8 normal subjects and 4 individuals with complete spinal cord lesion. Additionally, experimental studies were performed in 7 decerebrate and 4 spinal cats. Involuntary reflex stepping movements in the air were induced by vibrators attached above a tendon of m. rectus femoris and m. biceps femoris. In the spinal patients, epidural stimulation was carried out with electrodes located in the posterior epidural space at the vertebral level Th11. It was found that voluntary-induced stepping, which are accompanied by visceral reactions, were mediated by the central mechanisms. Changes in breathing pattern in response to vibration-induced involuntary stepping movements point up to the peripheral component being predominant in such interactions. In the spinal patients under epidural spinal cord stimulation delivered below the site of injury, the reaction in the cardio-respiratory system was abolished. Vibrations to the leg muscles also did not evoke respiratory responses. However, in the condition of forced breathing such vibrations evoked the rhythmic bursting EMG activity in m. rectus femoris, which was in harmony with the breathing rhythm. The results confirmed the presence of an interaction between breathing and stepping generators. This interaction is underlain both by central and peripheral components.
4
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Blockade of 5-HT1A receptors in the phrenic nucleus of the rat attenuated raphe induced activation of the phrenic nerve activity

100%
Pecotic R., Dogas Z., Valic Z., Valic M.
Journal of Physiology and Pharmacology
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2009
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tom 60
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nr 3
167-172
Stimulation of the raphe pallidus nucleus produces facilitatory effects on respiratory activity. Numerous serotonergic projections from the raphe pallidus have been shown to terminate in the phrenic nucleus. This study was undertaken to examine the role of 5-hydroxytryptamine 1A (5-HT1A) receptors in the phrenic nucleus on the excitatory response of the phrenic nerve activity elicited from the raphe pallidus. We hypothesized that blockade of 5-HT1A receptors in the phrenic nucleus will attenuate raphe-induced facilitation of the phrenic nerve. Chemical stimulation of the raphe pallidus by synaptic excitant D,L-homocysteic acid produced increase in the amplitude of the phrenic nerve activity. After microinjection of the specific 5-HT1A receptor antagonist WAY, N-(2-(4,2-methoxyphenyl)-1-piperazinyl)ethyl)-N-2-pyridinyl-cyclohexane-carboxamide maleate into the phrenic nucleus, the raphe-induced facilitation of the phrenic nerve was attenuated. These data suggest that excitation of the phrenic nerve activity elicited by activation of the neurons in the raphe pallidus is mediated by 5-HT1A receptors in the phrenic nucleus.
5
Content available remote

The potential role of the nodose ganglion adenosine A1 receptor in regulation of breathing in anaesthetized rats

100%
Kaczynska K., Szereda-Przestaszewska M.
Journal of Physiology and Pharmacology
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2008
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tom 59
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nr 4
759-770
The respiratory effects of stimulation of adenosine A1 receptors were studied in spontaneously breathing rats that were either (1) neurally intact and subsequently bilaterally vagotomized in the neck, or (2) neurally intact and subjected to supranodosal vagotomy or (3) midcervically vagotomized before and after pharmacological blockade of A1 receptors. Before neural interventions an intravenous bolus of the A1 receptor agonist N6-cyclopentyladenosine (CPA, 5 µg kg-1) decreased breathing rate, tidal volume, mean arterial blood pressure (MAP) and heart rate. After section of the midcervical vagi, CPA still decreased respiratory rate and tidal volume. Supranodose vagotomy abolished the fall in respiratory rate but did not affect the depression of tidal volume. Blockade of A1 receptors with intravenous doses of DPCPX (100 µg kg-1) eliminated all respiratory effects of CPA challenge. In all the neural states, CPA caused significant falls in mean arterial blood pressure and heart rate. DPCPX pre-treatment prevented these cardiovascular effects. The present data suggest that: (1) CPA-evoked activation of A1 receptors decreases breathing rate and tidal volume and this occurs central to the cervical vagi; (2) supranodosal vagotomy prevents the decrease in breathing rate, which is presumably due to stimulation of nodosal A1 receptor; and (3) depression of tidal volume and the hypotensive response result from the excitation of central nervous A1 expressing neurones.
6
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Divergent effects of bicuculline and picrotoxin on ketamine-induced apneustic breathing

100%
Budzinska K.
Journal of Physiology and Pharmacology. Supplement
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2005
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tom 56
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nr 4
39-46
This study tested the potential role of inhibitory neurotransmission in the mechanism of apneustic respiration evoked by ketamine, an NMDA receptors antagonist. In the experiments performed in anesthetized, paralyzed, and ventilated cats, ketamine, in a dose of 0.5 mg/kg, was administered before and after GABAA receptor blockade with picrotoxin or bicuculline; all agents were given intravenously. Ketamine elicited a transient, hourlong apneustic respiration consisting of an increase in inspiratory duration and a decrease in inspiratory neural amplitude. After prior administration of picrotoxin, but not bicuculline, the maximum apneustic-like prolongation of inspiration evoked by ketamine was considerably reduced. The results suggest that the GABA receptor subunits specifically sensitive to picrotoxin play a role in shaping the ketamine-induced apneustic breathing.
7
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Daily pattern of breathing in healthy young men

84%
Adamczyk W., Tafil-Klawe M., Siekierka M., Zlomanczuk P., Weber P., Klawe J. J.
Journal of Physiology and Pharmacology. Supplement
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2008
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tom 59
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nr 6
115-122
8
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Superoxide dismutase mimetic modulates hyperoxic augmentation of the diaphragmatic response to poikilocapnic hypoxia in non-vagotomized rats

84%
Budzinska K., Ilasz R.
Journal of Physiology and Pharmacology. Supplement
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2008
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tom 59
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nr 6
163-172
9
Content available remote

Sleep disordered breathing in the elderly: a three year longitudinal cohort study

84%
Hader C., Hinz M., Welz-Barth A., Rasche K.
Journal of Physiology and Pharmacology. Supplement
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2006
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tom 57
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nr 4
119-129
The objective of this investigation was to assess the association between the presence of sleep disordered breathing (SDB) and daytime sleepiness, body mass index, hospitalisation, and survival. To this end, a prospective longitudinal study was conducted in the elderly population consisting of 80 patients of either sex over the age of 65 years admitted to a city hospital in Germany without any history of SDB. All patients met the following exclusion criteria: age <65 yr, heart failure, and chronic obstructive lung disease. Baseline anthropometric and cardiorespiratory (one-night portable polygraphic recording) data, and a standardized sleep and sleepiness-questionnaires (Epworth Sleepiness Scale, ESS) were obtained in 1999. A second screening was conducted in 2003. Thirty one women and 34 men completed the follow-up after 3 years. These patients were divided into two subgroups: (i) no clinically relevant SDB and (ii) SDB (apnea-hypopnea index, AHI, 5 plus excessive day time sleepiness, ESS, >9). Six men and 3 women fulfilled the criteria of SDB. Thirty three percent of patients with SDB and 20% of patients without SDB died during the follow-up period. Duration of hospital stay was 35 days for the SDB patients and 20 days for patients without it. Body weight and sleepiness did not change significant over the 3-year period between the two cohorts. We conclude that the presence of SDB was associated with a 1.5-fold higher mortality and longer hospital stay in elderly patients over a period of 3 years even in persons without previous history of SDB. Daytime sleepiness was a better predictor than AHI or BMI for death.
10
Content available remote

Sleep and breathing in idiopathic pulmonary fibrosis

84%
Rasche K., Orth M.
Journal of Physiology and Pharmacology. Supplement
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2009
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tom 60
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nr 5
11
Content available remote

Effects of hypovolemia on hypercapnic ventilatory response in experimental hyperthermia

84%
Zila I., Brozmanova A., Javorka M., Calkovska A., Javorka K.
Journal of Physiology and Pharmacology. Supplement
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2007
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tom 58
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nr 5
12
Content available remote

Influence of the stimulation of carotid body chemoreceptors on the gastric mucosal blood flow in artificially ventilated and spontaneously breathing rats

84%
Sinski M., Kowalczyk P., Stolarczyk A., Sawionek L., Przybylski J.
Journal of Physiology and Pharmacology
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2002
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tom 53
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nr 3
The cardiovascular effects of the stimulation of arterial chemoreceptors are different in spontaneously breathing and artificially ventilated animals. Respiratory failure and long term sojourn at high altitude coincide frequently with the occurrence of gastric ulceration. In both these situations a profound stimulation of arterial chemoreceptors is present. The purpose of the paper was to investigate the reflex effect of stimulation carotid chemoreceptors on gastric mucosal blood flow in the rat. Arterial chemoreceptors were stimulated by two methods (I) substitution gas mixture of 10% oxygen in nitrogen for room air and (II) direct injection of acid saline ( 0.05 ml, pH=6.8) into the distal part of left common carotid artery. In artificially ventilated rats stimulation of arterial chemoreceptors caused significant increase in gastric mucosal vascular resistance, accompanied by marked decline in blood flow. This effect was mediated by adrenergic mechanism. On the contrary to artificially ventilated rats, decline of gastric mucosal vascular resistance with concomitant increase in blood flow was found in spontaneously breathing animals. This effect was not abolished either by phentolamine or atropine. As vasodilatatory effect of arterial chemoreceptors stimulation was abolished by bilateral vagotomy, we postulate that non adrenergic and non cholinergic vagal fibers mediate observed vascular changes in gastric mucosa in spontaneously breathing rats. We hypothesize that in artificially ventilated patients with respiratory failure stimulation of arterial chemoreceptors by hypoxemia and or acidosis may contribute to the development of gastric mucosal lesions.
13
Content available remote

Apnoeic responses to intracarotid nicotine challenge in anaesthetized cats

84%
Szereda-Przestaszewska M., Kopczynska B.
Journal of Physiology and Pharmacology
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2003
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tom 54
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nr 2
To determine the effects of an intraarterial administration of nicotine on the occurrence of apnoea and the activity of rib cage respiratory muscles, we studied 31 anaesthetized, spontaneously breathing cats. Phrenic activity was used as an index of neural inspiratory drive. Activity of parasternal intercostal (PIM) and triangularis sterni (TS) muscles was recorded. Nicotine in a dose of 65 µg/kg was injected into the left common carotid artery prior to and after midcervical vagotomy, preceded by section of the superior laryngeal nerves (SLNs). In eight additional cats, initially neurotomized as mentioned, nicotine was injected after bilateral disruption of the carotid sinus nerves (CSNs). Nicotine induced prompt expiratory apnoea of mean duration of 5.4±0.3 s in 19 non-vagotomized and of 5.92±0.51 s (mean±S.E.M.) in 13 vagotomized cats. The occurrence and duration of the temporary arrest of breathing were reduced by midcervical vagotomy but not by subsequent CSNs neurotomy, which abolished post-apnoeic acceleration of breathing.In post-nicotine breathing of increased tidal volume and respiratory rate, peak activity of the parasternal intercostal muscles increased from baseline of 3.2±1.2 to 9.5±2.0 arbitrary units (p<0.001). The peak height of the phrenic nerve elevated from 7.9±0.9 to 14.5±1.7 arbitrary units (p<0.001). That of the triangularis sterni showed no change.The response of the respiratory effectors elicited by nicotine was independent of the vagal integrity and may be attributed to activation of nicotine receptors within the brainstem respiratory neurones.
14

Superior laryngeal nerve section abolishes capsaicin evoked chemoreflex in anaesthetized rats

84%
Kaczynska K., Szereda-Przestaszewska M.
Acta Neurobiologiae Experimentalis
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2002
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tom 62
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nr 1
15
Content available remote

Effects of oxygen breathing on inspiratory muscle fatigue during resistive load in cycling men

67%
Segizbaeva M. O., Aleksandrova N. P.
Journal of Physiology and Pharmacology. Supplement
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2009
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tom 60
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nr 5
16

Wplyw treningu na wybrane parametry hematologiczne u koni sportowych

67%
Neuberg K., Geringer de Oedenberg H.
Acta Scientiarum Polonorum. Zootechnica
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2007
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tom 06
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nr 4
59-68
17
Content available remote

The incidence of sleep apnea in patients with stroke or transient ischemic attack

67%
Wierzbicka A., Rola R., Wichniak A., Richter P., Ryglewicz D., Jernajczyk W.
Journal of Physiology and Pharmacology. Supplement
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2006
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tom 57
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nr 4
385-390
Disorders of breathing during sleep are defined as cessation or reduction of air flow thorough the upper airway, accompanied by a decrease of oxygen saturation. The results of many studies underline the association between sleep-disordered breathing (SDB) and cerebrovascular disorders. SDB, mostly obstructive sleep apnea syndrome (OSAS), is believed to be an independent risk factor of stroke and is related to poor outcome and increased long-term stroke mortality. The present study evaluated the frequency of SDB in patients with stroke or transient ischemic attack transient ischemic attack. We studied 43 patients (mean age 68.5 ±11.0), which included 35 males and 8 females, with acute stroke (n=37) and transient ischemic attack (n=6). The assessment included body mass index (BMI), age, cardiovascular risk factors, and localization of stroke. All patients underwent all-night screening for SDB with a portable 8-channel recorder. The apnea/hypopnea index (AHI) for the whole group was 13.3 ±15.2. AHI <5 was found in 16 patients. Overall, SDB was present in 27 (62.8%) patients with stroke and transient ischemic attack, stratified into those with AHI 5-10, (10 patients), 10-20 (8 patients), and AHI>20 (9 patients). In 15 patients, there was an increase in AHI 5 on assuming the supine position. The patients’ mean BMI was 27.8 ±4.7. The analysis of BMI, age, and localization of stroke was not sufficient to identify patients with high risk for SDB. We submit that overnight screening for SDB should be routinely performed in every patient after stroke and transient ischemic attack and it should become a diagnostic tool in neurological departments.
18

Horseradish peroxidase localization of the mylohyoid motoneurones in the rabbit

59%
Gromysz H., Karczewski W. A., Kosmal A., Kukwa A.
Acta Neurobiologiae Experimentalis
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1993
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tom 53
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nr 2
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