Nejvíce citovaný článek - PubMed ID 20926760
In order to clear airways and lungs defensive reflexes are provoked rather by the dynamic phase of mechanical stimulus. It is speculated that provocation of defensive response depends not only on stimulus duration but also on stimulus velocity. Fourteen adult rabbits were anaesthetized and tracheotomized. Mechanical stimulus was provoked by a mechanical probe introduced through the tracheotomy and rotated by a small electrical motor using a rotational velocity of 40 rpm/s and 20 rpm/s. Threshold, incidence and intensity of cough reflex (CR) were analyzed for each animal. Statistical comparisons between two velocities were performed using Friedman nonparametric test for repeated measurements. Results are median (25-75 %). The threshold of CR was significantly increased (p=0.005) from 350 ms (300-500 ms) to 550 ms (350-1150 ms) and the incidence of cough reflex was significantly reduced (p=0.002) from 50 % (19 50 %) to 0 % (0-25 %) when the rotational velocity of the mechanical probe was reduced by half. The findings of this study are of interest as they show that protective reflex cough, an important mechanism that allows clearing airways even during sleep or anesthesia, is tuned by mechanical stimulus velocity.
- MeSH
- dechový objem fyziologie MeSH
- fyzikální stimulace škodlivé účinky MeSH
- kašel etiologie patofyziologie MeSH
- králíci MeSH
- plíce patofyziologie MeSH
- reflex fyziologie MeSH
- trachea patofyziologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Cough is one of the most important defensive reflexes. However, extensive non- productive cough is a harmful mechanism leading to the damage of human airways. Cough is initiated by activation of vagal afferents in the airways. The site of their convergence is particularly the nucleus of the solitary tract (nTS). The second-order neurons terminate in the pons, medulla and spinal cord and there is also the cortical and subcortical control of coughing.Upper airway cough syndrome (UACS) - previously postnasal drip syndrome - is one of the most common causes of chronic cough together with asthma and gastroesophageal reflux. The main mechanisms leading to cough in patients with nasal and sinus diseases are postnasal drip, direct irritation of nasal mucosa, inflammation in the lower airways, upper airway inflammation and the cough reflex sensitization. The cough demonstrated by UACS patients is probably due to hypersensitivity of the upper airways sensory nerve or lower airways sensory nerve, or a combination of both. Further studies are needed to clarify this mechanism.
- MeSH
- chronická nemoc MeSH
- kapsaicin škodlivé účinky MeSH
- kašel chemicky indukované patofyziologie MeSH
- kationtové kanály TRPV agonisté fyziologie MeSH
- kationtový kanál TRPA1 agonisté fyziologie MeSH
- lidé MeSH
- nervové receptory účinky léků fyziologie MeSH
- nervus vagus účinky léků patofyziologie MeSH
- nosní sliznice účinky léků patofyziologie MeSH
- syndrom MeSH
- trachea účinky léků patofyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- kapsaicin MeSH
- kationtové kanály TRPV MeSH
- kationtový kanál TRPA1 MeSH
- TRPA1 protein, human MeSH Prohlížeč
- TRPV1 protein, human MeSH Prohlížeč
Laboratory research of cough reflex utilizes almost exclusively male guinea pigs - a practice that represents a significant obstacle in the successful translation of results into clinical practice. Chronic hypersensitivity cough syndrome affects mostly postmenopausal women and it represents significant decrease in patient's quality of life. No cause for such exaggerated cough can be found, therefore this condition cannot be treated appropriately. One of the reasons leading to the lack of relevant data about mechanisms responsible for hypersensitivity of cough related pathways is nowadays widely discussed gender bias, which is present in nearly all branches of biomedical research. Since gender differences in cough reflex physiology do exist in humans, it would be reasonable to study cough-related phenomena on both sexes of laboratory animals. In this study, we focused on detailed characterization of cough response of female guinea pigs to aerosols of commonly used tussive agents (capsaicin, distilled water, allyl isothiocyanate, cinnamaldehyde, citric acid). In pooled data from multiple challenges we found no statistical difference in number of cough and cough latency between sexes. Based on our results we conclude that the utilization of female guinea pigs model does not lead to messy data and can be used in basic cough research.
- MeSH
- akrolein analogy a deriváty toxicita MeSH
- kapsaicin toxicita MeSH
- kašel chemicky indukované patofyziologie MeSH
- kyselina citronová toxicita MeSH
- modely nemocí na zvířatech * MeSH
- morčata MeSH
- pohlavní dimorfismus * MeSH
- zvířata MeSH
- Check Tag
- morčata MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- akrolein MeSH
- cinnamaldehyde MeSH Prohlížeč
- kapsaicin MeSH
- kyselina citronová MeSH