- Email: [email protected]
Results from recent spaceflight experiments (1)
Respiratory Physiology & Neurobiology 169S (2009) S4–S5
Contents lists available at ScienceDirect
Respiratory Physiology & Neurobiology journal homepage: www.elsevier.com/locate/resphysiol
Results from recent spaceflight experiments (1)夽 Uwe Hoffmann ∗ Department of Physiology and Anatomy, German Sport University Cologne, 50927 Cologne, Germany
a r t i c l e
i n f o
Article history: Accepted 5 May 2009
a b s t r a c t Since the flight of Sputnik 2 in 1957 the effects of weightlessness on the cardiovascular regulation are subject of physiological research. This introduction gives a short summary of the further development of cardiovascular research related to weightlessness which was subject of the contributions to the first part of this workshop. © 2009 Elsevier B.V. All rights reserved.
1. The cardiovascular system in space Since the first orbital flight of mammals with Sputnik 2 in 1957 cardiovascular research is the subject of space experiments (Grigori’ev and Il’in, 2007). Acute changes of gravity down to 0 Gz+ and back to 1 Gz+ are related to the changes of hydrostatic pressure. The magnitude of these pressure changes is comparable to position changes from upright to supine and therefore within the normal range of demands for the cardiovascular regulation. In this sense, the cardiovascular research in the context of spaceflight does not mean research of extraordinary stress for the organism. However, this is the perspective for a 1 Gz+adapted organism. After adaptation to a 0 Gz+ environment any increase in gravity might become a challenge for the cardiovascular regulation. The focus of research is related to prolongation of space exposure implying chronic multi-factorial stress and its consequences for the return to Earth: • • • • • • •
reduction of blood volume; changes in baroreflex; changes in chemical parameters of blood; reduction of metabolic demands of the whole body; changes in proprio-receptions; less demanding acute regulations; psychogenic factors.
2. Inflight monitoring of cardiovascular parameters This scenario on one hand requires monitoring of cardiovascular parameters as indicators for vital functions for the operational
夽 This paper is part of a supplement entitled “Cardio-Respiratory Physiology in Space”, guest-edited by P. Norsk and D. Linnarsson. ∗ Tel.: +49 221 49822910; fax: +49 221 49826790. E-mail address: [email protected]. 1569-9048/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.resp.2009.05.001
medicine. On the other hand spaceflight developed as a test bed for manifold scientific questions and demands. Both aspects raised methodological requirements: • the development of adequate space qualified instrumentation; • the development and adaptation of methods to investigate adaptation processes in details; • a distinction of the singular effects in the list above; • the development of countermeasures to preserve cardiovascular functions. Extensive cardiovascular research is associated with the space stations launched by Russians (Salyut/MIR) and NASA (Skylab) since the 1970s. The scenario of controlled measurements was further improved with the start-up of the first ESA spacelab onboard the NASA Shuttle mission STS-9 (1983) and the succeeding developments. One important milestone was the ESA-Anthrorack concept of a multi-purpose and multi-user facility for human physiology including several instruments for cardiovascular research (Oser, 1984). An echo-doppler device and the respiratory monitoring system allowing the determination of cardiac output by rebreathing techniques were elements from the early phases of development. Due to the Challenger accident in 1986 the launch of Anthrorack was delayed until 1993. In the meantime after 1986 several MIR missions were performed where cardiovascular research in space was expedited. A typical example is the MIR-Antares (1992) mission (Arbeille et al., 1995). Other MIR missions arranged by France, Germany, ESA, and the Russians themselves generated valuable contributions in the area of cardiovascular research. For the development of specific instruments the experience of the Anthrorack project gave important inputs although the multi-purpose concept was reduced to a more modular and therefore more flexible concept. Most instruments and methods used in space were tested during parabolic flights. This test bed gives the only opportunity for a real 0 Gz+ environment but these experiments also give valid results
U. Hoffmann / Respiratory Physiology & Neurobiology 169S (2009) S4–S5
for responses to acute changes of gravity. In this sense, the first contribution to this section (Caiani et al., this issue) combines both, the proof of applicability of the method in the 0 Gz+ environment and the scientific questions related to acute changes in gravity. The experimental results from several shuttle flights improve the knowledge about short duration (<16 d) adaptations and the effect of potential countermeasures (e.g. Di Rienzo et al., 2008). With the launch of the International Space Station (ISS) the adaptations to prolonged 0 Gz+ exposures can be studied extensively. The Columbia tragedy in 2003 delayed the completion of the station but already the first years in operation produced some interesting results. The ensemble of space qualified instruments like ESA’s Pulmonary Function System (PFS), its portable version (PPFS) and the approved Continuous Blood Pressure Device (CBPD) give a high flexibility for a wide range of experiment with different types of stress devices. 3. Contributions to the workshop The adaptation of the autonomic nervous system to sustained 0 Gz+ and the consequences for cardiovascular control are in the focus of the investigations in this section. The understanding of changes in heart rate control and blood pressure control are important to develop devices and methods for efficient countermeasures. The papers from Coupé et al. (2009) and Verheyden et al. (in press) demonstrate that modern instrumentation and new concepts of data analysis allow a deeper insight to the consequences induced by long-term exposure to 0 Gz+. The presentation by P.-F. Migeotte
S5
(contribution not included in this supplement) tackled one important aspect of cardiovascular research especially in space: the reactions of cardiovascular parameters are significantly influenced by other physiological parameters. The control and recognition of those related parameter are of importance. Due to the changes in hydrostatic pressure even pressure changes by respiration will affect the cardiovascular control (Migeotte et al., 2003). References Arbeille, Ph., Fominat, G., Achaibou, F., Pottier, J., Kotovskayaf, A., 1995. Cardiac and vascular adaptation to 0 g with and without thigh cuffs (Antares 14 and Altair 21 day Mir spaceflights). Acta Astronaut. 36, 753–762. Caiani, E.G., Lang, R.M., Weinert, L., Vaïda, P., this issue. The role of echocardiography in the assessment of cardiac function in weightlessness—our experience during parabolic flights. Respir. Physiol. Coupé, M., Fortrat, J.O., Larina, I., Gauquelin-Koch, G., Gharib, C., Custaud, M.A., 2009. Cardiovascular deconditioning: from autonomic nervous system to microvascular dysfunctions. Respir. Physiol. 169 (Suppl.), S10–S12. Di Rienzo, M., Castiglioni, P., Iellamo, F., Volterrani, M., Pagani, M., Mancia, G., Karemaker, J.M., Parati, G., 2008. Dynamic adaptation of cardiac baroreflex sensitivity to prolonged exposure to microgravity: data from a 16-day spaceflight. J. Appl. Physiol. 105, 1569–1575. Grigori’ev, A.I., Il’in, E.A., 2007. Animals in space—on the 50th anniversary of space biology. Herald Russ. Acad. Sci. 77, 541–549. Migeotte, P.-F., Prisk, G.K., Paiva, M., 2003. Microgravity alters respiratory sinus arrhythmia and short-term heart rate variability in humans. Am. J. Physiol. Heart Circ. Physiol. 284, H1995–H2006. Oser, H., 1984. Life sciences within ESA’s microgravity research programme. ESA: Life Sciences Research in Space. ESA-SP 212, 285–286. Verheyden, B., Liu, J., Beckers, F., Aubert, A.E., 2009. Evolution of heart rate and blood pressure in short and long duration space missions. Respir. Physiol. 169 (Suppl.), S13–S16.
Contents lists available at ScienceDirect
Respiratory Physiology & Neurobiology journal homepage: www.elsevier.com/locate/resphysiol
Results from recent spaceflight experiments (1)夽 Uwe Hoffmann ∗ Department of Physiology and Anatomy, German Sport University Cologne, 50927 Cologne, Germany
a r t i c l e
i n f o
Article history: Accepted 5 May 2009
a b s t r a c t Since the flight of Sputnik 2 in 1957 the effects of weightlessness on the cardiovascular regulation are subject of physiological research. This introduction gives a short summary of the further development of cardiovascular research related to weightlessness which was subject of the contributions to the first part of this workshop. © 2009 Elsevier B.V. All rights reserved.
1. The cardiovascular system in space Since the first orbital flight of mammals with Sputnik 2 in 1957 cardiovascular research is the subject of space experiments (Grigori’ev and Il’in, 2007). Acute changes of gravity down to 0 Gz+ and back to 1 Gz+ are related to the changes of hydrostatic pressure. The magnitude of these pressure changes is comparable to position changes from upright to supine and therefore within the normal range of demands for the cardiovascular regulation. In this sense, the cardiovascular research in the context of spaceflight does not mean research of extraordinary stress for the organism. However, this is the perspective for a 1 Gz+adapted organism. After adaptation to a 0 Gz+ environment any increase in gravity might become a challenge for the cardiovascular regulation. The focus of research is related to prolongation of space exposure implying chronic multi-factorial stress and its consequences for the return to Earth: • • • • • • •
reduction of blood volume; changes in baroreflex; changes in chemical parameters of blood; reduction of metabolic demands of the whole body; changes in proprio-receptions; less demanding acute regulations; psychogenic factors.
2. Inflight monitoring of cardiovascular parameters This scenario on one hand requires monitoring of cardiovascular parameters as indicators for vital functions for the operational
夽 This paper is part of a supplement entitled “Cardio-Respiratory Physiology in Space”, guest-edited by P. Norsk and D. Linnarsson. ∗ Tel.: +49 221 49822910; fax: +49 221 49826790. E-mail address: [email protected]. 1569-9048/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.resp.2009.05.001
medicine. On the other hand spaceflight developed as a test bed for manifold scientific questions and demands. Both aspects raised methodological requirements: • the development of adequate space qualified instrumentation; • the development and adaptation of methods to investigate adaptation processes in details; • a distinction of the singular effects in the list above; • the development of countermeasures to preserve cardiovascular functions. Extensive cardiovascular research is associated with the space stations launched by Russians (Salyut/MIR) and NASA (Skylab) since the 1970s. The scenario of controlled measurements was further improved with the start-up of the first ESA spacelab onboard the NASA Shuttle mission STS-9 (1983) and the succeeding developments. One important milestone was the ESA-Anthrorack concept of a multi-purpose and multi-user facility for human physiology including several instruments for cardiovascular research (Oser, 1984). An echo-doppler device and the respiratory monitoring system allowing the determination of cardiac output by rebreathing techniques were elements from the early phases of development. Due to the Challenger accident in 1986 the launch of Anthrorack was delayed until 1993. In the meantime after 1986 several MIR missions were performed where cardiovascular research in space was expedited. A typical example is the MIR-Antares (1992) mission (Arbeille et al., 1995). Other MIR missions arranged by France, Germany, ESA, and the Russians themselves generated valuable contributions in the area of cardiovascular research. For the development of specific instruments the experience of the Anthrorack project gave important inputs although the multi-purpose concept was reduced to a more modular and therefore more flexible concept. Most instruments and methods used in space were tested during parabolic flights. This test bed gives the only opportunity for a real 0 Gz+ environment but these experiments also give valid results
U. Hoffmann / Respiratory Physiology & Neurobiology 169S (2009) S4–S5
for responses to acute changes of gravity. In this sense, the first contribution to this section (Caiani et al., this issue) combines both, the proof of applicability of the method in the 0 Gz+ environment and the scientific questions related to acute changes in gravity. The experimental results from several shuttle flights improve the knowledge about short duration (<16 d) adaptations and the effect of potential countermeasures (e.g. Di Rienzo et al., 2008). With the launch of the International Space Station (ISS) the adaptations to prolonged 0 Gz+ exposures can be studied extensively. The Columbia tragedy in 2003 delayed the completion of the station but already the first years in operation produced some interesting results. The ensemble of space qualified instruments like ESA’s Pulmonary Function System (PFS), its portable version (PPFS) and the approved Continuous Blood Pressure Device (CBPD) give a high flexibility for a wide range of experiment with different types of stress devices. 3. Contributions to the workshop The adaptation of the autonomic nervous system to sustained 0 Gz+ and the consequences for cardiovascular control are in the focus of the investigations in this section. The understanding of changes in heart rate control and blood pressure control are important to develop devices and methods for efficient countermeasures. The papers from Coupé et al. (2009) and Verheyden et al. (in press) demonstrate that modern instrumentation and new concepts of data analysis allow a deeper insight to the consequences induced by long-term exposure to 0 Gz+. The presentation by P.-F. Migeotte
S5
(contribution not included in this supplement) tackled one important aspect of cardiovascular research especially in space: the reactions of cardiovascular parameters are significantly influenced by other physiological parameters. The control and recognition of those related parameter are of importance. Due to the changes in hydrostatic pressure even pressure changes by respiration will affect the cardiovascular control (Migeotte et al., 2003). References Arbeille, Ph., Fominat, G., Achaibou, F., Pottier, J., Kotovskayaf, A., 1995. Cardiac and vascular adaptation to 0 g with and without thigh cuffs (Antares 14 and Altair 21 day Mir spaceflights). Acta Astronaut. 36, 753–762. Caiani, E.G., Lang, R.M., Weinert, L., Vaïda, P., this issue. The role of echocardiography in the assessment of cardiac function in weightlessness—our experience during parabolic flights. Respir. Physiol. Coupé, M., Fortrat, J.O., Larina, I., Gauquelin-Koch, G., Gharib, C., Custaud, M.A., 2009. Cardiovascular deconditioning: from autonomic nervous system to microvascular dysfunctions. Respir. Physiol. 169 (Suppl.), S10–S12. Di Rienzo, M., Castiglioni, P., Iellamo, F., Volterrani, M., Pagani, M., Mancia, G., Karemaker, J.M., Parati, G., 2008. Dynamic adaptation of cardiac baroreflex sensitivity to prolonged exposure to microgravity: data from a 16-day spaceflight. J. Appl. Physiol. 105, 1569–1575. Grigori’ev, A.I., Il’in, E.A., 2007. Animals in space—on the 50th anniversary of space biology. Herald Russ. Acad. Sci. 77, 541–549. Migeotte, P.-F., Prisk, G.K., Paiva, M., 2003. Microgravity alters respiratory sinus arrhythmia and short-term heart rate variability in humans. Am. J. Physiol. Heart Circ. Physiol. 284, H1995–H2006. Oser, H., 1984. Life sciences within ESA’s microgravity research programme. ESA: Life Sciences Research in Space. ESA-SP 212, 285–286. Verheyden, B., Liu, J., Beckers, F., Aubert, A.E., 2009. Evolution of heart rate and blood pressure in short and long duration space missions. Respir. Physiol. 169 (Suppl.), S13–S16.