A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption
Discontinuous respiration in diapausing pupae of Cecropia silkworms was monitored by means of several electronic methods, including recording changes in haemocoelic pressure, monitoring respiratory movements by strain-gauge sensors and nanorespirographic recording of O2 consumption and CO2 output. I...
Published in: | European Journal of Entomology |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Institute of Entomology, Biology Centre, Czech Academy of Science
2010
|
Subjects: | |
Online Access: | https://doi.org/10.14411/eje.2010.057 https://doaj.org/article/75ad336a4b844f8aab2a8016685ed1af |
id |
ftdoajarticles:oai:doaj.org/article:75ad336a4b844f8aab2a8016685ed1af |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:75ad336a4b844f8aab2a8016685ed1af 2023-05-15T15:52:56+02:00 A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption Karel SLÁMA 2010-10-01T00:00:00Z https://doi.org/10.14411/eje.2010.057 https://doaj.org/article/75ad336a4b844f8aab2a8016685ed1af EN eng Institute of Entomology, Biology Centre, Czech Academy of Science https://www.eje.cz/artkey/eje-201004-0003_A_new_look_at_discontinuous_respiration_in_pupae_of_Hyalophora_cecropia_Lepidoptera_Saturniidae_Haemocoelic.php https://doaj.org/toc/1210-5759 https://doaj.org/toc/1802-8829 1210-5759 1802-8829 doi:10.14411/eje.2010.057 https://doaj.org/article/75ad336a4b844f8aab2a8016685ed1af European Journal of Entomology, Vol 107, Iss 4, Pp 487-507 (2010) saturniidae hyalophora cecropia respiratory acidaemia haemocoelic pulsations respiratory movements o2 consumption spiracular pulsations co2 bursts chemically produced co2 carbonic anhydrase Zoology QL1-991 article 2010 ftdoajarticles https://doi.org/10.14411/eje.2010.057 2022-12-31T10:45:54Z Discontinuous respiration in diapausing pupae of Cecropia silkworms was monitored by means of several electronic methods, including recording changes in haemocoelic pressure, monitoring respiratory movements by strain-gauge sensors and nanorespirographic recording of O2 consumption and CO2 output. It appears that, in contrast to previous concepts of stereotypic discontinuous respiration cycles (DGC) driven by accumulation of gaseous CO2 in the body, the new results indicate that CO2 remains dissolved in liquid carbonate buffers during interburst periods. In other words, there is no accumulation of gaseous CO2 within the air filled tracheal space between the bursts. The bursts of CO2 are caused by homeostatically regulated enzymatic hydration by carbonic anhydrase of metabolically produced carbonic acid. The chemically produced gaseous CO2 was exhaled mainly by a bulk outflow through selectively opened or pulsating spiracles. The output of CO2 was enhanced by actively regulated, unidirectional ventilation. The deep depressions in haemocoelic pressure, caused by permanent closure of all spiracular valves for long periods, appeared to be a specific feature of diapausing saturniid pupae. Physiologically, it has circulatory, not respiratory functions. The original definition of spiracular "fluttering" resulted from a misinterpretation of previously unknown extracardiac pulsations in haemocoelic pressure. The coordinated pulsation of the spiracular valves with extracardiac pulsations produce a very efficient, unidirectional ventilation of the whole tracheal system. According to the new results, the discontinuous respiration cycles of diapausing Cecropia pupae can be briefly described as follows: (1) Spiracular valves are kept permanently closed during the periods of deep depressions, they remain closed for some 99% of the time with occasional snap opening (passive inspirations) during prolonged interburst periods and more than 50% closed during the bursts; (2) During the long interburst periods, CO2 is retained in ... Article in Journal/Newspaper Carbonic acid Directory of Open Access Journals: DOAJ Articles European Journal of Entomology 107 4 487 507 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
saturniidae hyalophora cecropia respiratory acidaemia haemocoelic pulsations respiratory movements o2 consumption spiracular pulsations co2 bursts chemically produced co2 carbonic anhydrase Zoology QL1-991 |
spellingShingle |
saturniidae hyalophora cecropia respiratory acidaemia haemocoelic pulsations respiratory movements o2 consumption spiracular pulsations co2 bursts chemically produced co2 carbonic anhydrase Zoology QL1-991 Karel SLÁMA A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption |
topic_facet |
saturniidae hyalophora cecropia respiratory acidaemia haemocoelic pulsations respiratory movements o2 consumption spiracular pulsations co2 bursts chemically produced co2 carbonic anhydrase Zoology QL1-991 |
description |
Discontinuous respiration in diapausing pupae of Cecropia silkworms was monitored by means of several electronic methods, including recording changes in haemocoelic pressure, monitoring respiratory movements by strain-gauge sensors and nanorespirographic recording of O2 consumption and CO2 output. It appears that, in contrast to previous concepts of stereotypic discontinuous respiration cycles (DGC) driven by accumulation of gaseous CO2 in the body, the new results indicate that CO2 remains dissolved in liquid carbonate buffers during interburst periods. In other words, there is no accumulation of gaseous CO2 within the air filled tracheal space between the bursts. The bursts of CO2 are caused by homeostatically regulated enzymatic hydration by carbonic anhydrase of metabolically produced carbonic acid. The chemically produced gaseous CO2 was exhaled mainly by a bulk outflow through selectively opened or pulsating spiracles. The output of CO2 was enhanced by actively regulated, unidirectional ventilation. The deep depressions in haemocoelic pressure, caused by permanent closure of all spiracular valves for long periods, appeared to be a specific feature of diapausing saturniid pupae. Physiologically, it has circulatory, not respiratory functions. The original definition of spiracular "fluttering" resulted from a misinterpretation of previously unknown extracardiac pulsations in haemocoelic pressure. The coordinated pulsation of the spiracular valves with extracardiac pulsations produce a very efficient, unidirectional ventilation of the whole tracheal system. According to the new results, the discontinuous respiration cycles of diapausing Cecropia pupae can be briefly described as follows: (1) Spiracular valves are kept permanently closed during the periods of deep depressions, they remain closed for some 99% of the time with occasional snap opening (passive inspirations) during prolonged interburst periods and more than 50% closed during the bursts; (2) During the long interburst periods, CO2 is retained in ... |
format |
Article in Journal/Newspaper |
author |
Karel SLÁMA |
author_facet |
Karel SLÁMA |
author_sort |
Karel SLÁMA |
title |
A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption |
title_short |
A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption |
title_full |
A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption |
title_fullStr |
A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption |
title_full_unstemmed |
A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption |
title_sort |
new look at discontinuous respiration in pupae of hyalophora cecropia (lepidoptera: saturniidae): haemocoelic pressure, extracardiac pulsations and o2 consumption |
publisher |
Institute of Entomology, Biology Centre, Czech Academy of Science |
publishDate |
2010 |
url |
https://doi.org/10.14411/eje.2010.057 https://doaj.org/article/75ad336a4b844f8aab2a8016685ed1af |
genre |
Carbonic acid |
genre_facet |
Carbonic acid |
op_source |
European Journal of Entomology, Vol 107, Iss 4, Pp 487-507 (2010) |
op_relation |
https://www.eje.cz/artkey/eje-201004-0003_A_new_look_at_discontinuous_respiration_in_pupae_of_Hyalophora_cecropia_Lepidoptera_Saturniidae_Haemocoelic.php https://doaj.org/toc/1210-5759 https://doaj.org/toc/1802-8829 1210-5759 1802-8829 doi:10.14411/eje.2010.057 https://doaj.org/article/75ad336a4b844f8aab2a8016685ed1af |
op_doi |
https://doi.org/10.14411/eje.2010.057 |
container_title |
European Journal of Entomology |
container_volume |
107 |
container_issue |
4 |
container_start_page |
487 |
op_container_end_page |
507 |
_version_ |
1766388032041123840 |