Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep
Abstract Both adrenomedullin 2 (AM2) and sympathetic nerve activity (SNA) have been shown to be involved in regulating cardiovascular activity, but whether any interaction between these two systems exists remains to be determined. In this study, we examine the effects of intravenous AM2 infusions on...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2019-05-01
|
| Series: | Physiological Reports |
| Subjects: | |
| Online Access: | https://doi.org/10.14814/phy2.14096 |
| _version_ | 1811331609381568512 |
|---|---|
| author | Christopher J. Charles David L. Jardine Miriam T. Rademaker A. Mark Richards |
| author_facet | Christopher J. Charles David L. Jardine Miriam T. Rademaker A. Mark Richards |
| author_sort | Christopher J. Charles |
| collection | DOAJ |
| description | Abstract Both adrenomedullin 2 (AM2) and sympathetic nerve activity (SNA) have been shown to be involved in regulating cardiovascular activity, but whether any interaction between these two systems exists remains to be determined. In this study, we examine the effects of intravenous AM2 infusions on SNA directed toward the heart (cardiac SNA (CSNA)) in healthy sheep studied in the conscious state. In response to AM2, arterial pressure was reduced (P = 0.005) with both heart rate (P < 0.001) and cardiac output (P < 0.001) increased compared with vehicle control response. CSNA burst frequency (bursts/min) and burst area/min both increased during infusion of AM2 (both P < 0.001). However, correcting CSNA indices for concurrent heart rate changes resulted in CSNA burst incidence (bursts/100 beats) and burst area incidence (area/100 beats) being not significantly different between AM2 and control treatments. There were no significant differences demonstrated in plasma epinephrine or norepinephrine levels between the two study days. In conclusion, AM2 administered systemically to normal conscious sheep increases both CSNA and heart rate. However, correction for heart rate responses abrogates the rise in CSNA. It remains unclear whether AM2's primary effect is to act via the central nervous system to directly stimulate CSNA with resultant increase in heart rate, or to induce a rise in heart rate by other mechanisms. |
| first_indexed | 2024-04-13T16:23:18Z |
| format | Article |
| id | doaj.art-af90cab264904654bda15fa003fc5909 |
| institution | Directory Open Access Journal |
| issn | 2051-817X |
| language | English |
| last_indexed | 2024-04-13T16:23:18Z |
| publishDate | 2019-05-01 |
| publisher | Wiley |
| record_format | Article |
| series | Physiological Reports |
| spelling | doaj.art-af90cab264904654bda15fa003fc59092022-12-22T02:39:51ZengWileyPhysiological Reports2051-817X2019-05-01710n/an/a10.14814/phy2.14096Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheepChristopher J. Charles0David L. Jardine1Miriam T. Rademaker2A. Mark Richards3Department of Medicine Christchurch Heart Institute University of Otago Christchurch Christchurch New ZealandDepartment of Medicine Christchurch Heart Institute University of Otago Christchurch Christchurch New ZealandDepartment of Medicine Christchurch Heart Institute University of Otago Christchurch Christchurch New ZealandDepartment of Medicine Christchurch Heart Institute University of Otago Christchurch Christchurch New ZealandAbstract Both adrenomedullin 2 (AM2) and sympathetic nerve activity (SNA) have been shown to be involved in regulating cardiovascular activity, but whether any interaction between these two systems exists remains to be determined. In this study, we examine the effects of intravenous AM2 infusions on SNA directed toward the heart (cardiac SNA (CSNA)) in healthy sheep studied in the conscious state. In response to AM2, arterial pressure was reduced (P = 0.005) with both heart rate (P < 0.001) and cardiac output (P < 0.001) increased compared with vehicle control response. CSNA burst frequency (bursts/min) and burst area/min both increased during infusion of AM2 (both P < 0.001). However, correcting CSNA indices for concurrent heart rate changes resulted in CSNA burst incidence (bursts/100 beats) and burst area incidence (area/100 beats) being not significantly different between AM2 and control treatments. There were no significant differences demonstrated in plasma epinephrine or norepinephrine levels between the two study days. In conclusion, AM2 administered systemically to normal conscious sheep increases both CSNA and heart rate. However, correction for heart rate responses abrogates the rise in CSNA. It remains unclear whether AM2's primary effect is to act via the central nervous system to directly stimulate CSNA with resultant increase in heart rate, or to induce a rise in heart rate by other mechanisms.https://doi.org/10.14814/phy2.14096Arterial pressurecardiac outputsympathetic nervous system |
| spellingShingle | Christopher J. Charles David L. Jardine Miriam T. Rademaker A. Mark Richards Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep Physiological Reports Arterial pressure cardiac output sympathetic nervous system |
| title | Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep |
| title_full | Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep |
| title_fullStr | Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep |
| title_full_unstemmed | Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep |
| title_short | Adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep |
| title_sort | adrenomedullin 2 increases cardiac sympathetic nerve activity in parallel to heart rate in normal conscious sheep |
| topic | Arterial pressure cardiac output sympathetic nervous system |
| url | https://doi.org/10.14814/phy2.14096 |
| work_keys_str_mv | AT christopherjcharles adrenomedullin2increasescardiacsympatheticnerveactivityinparalleltoheartrateinnormalconscioussheep AT davidljardine adrenomedullin2increasescardiacsympatheticnerveactivityinparalleltoheartrateinnormalconscioussheep AT miriamtrademaker adrenomedullin2increasescardiacsympatheticnerveactivityinparalleltoheartrateinnormalconscioussheep AT amarkrichards adrenomedullin2increasescardiacsympatheticnerveactivityinparalleltoheartrateinnormalconscioussheep |