Advertisement

The Journal of Physiological Sciences

, Volume 67, Issue 5, pp 629–635 | Cite as

An in vitro experimental model for analysis of central control of sympathetic nerve activity

  • Yuji Oyama
  • Kamon Iigaya
  • Yoshino Minoura
  • Toshitaka Okabe
  • Masahiko Izumizaki
  • Hiroshi OnimaruEmail author
Technical Note

Abstract

Newborn rat brainstem-spinal cord preparations are useful for in vitro analysis of various brainstem functions including respiratory activity. When studying the central control of sympathetic nerve activity (SNA), it is important to record peripheral outputs of the SNA. We developed an in vitro preparation in which neuronal connections between the cardiovascular center in the medulla and SNA peripheral outputs are preserved. Zero- to 1-day-old rats were deeply anesthetized with isoflurane, and the brainstem and spinal cord were isolated with a partial right thoracic cage to record sympathetic nerve discharge from the right thoracic sympathetic nerve trunk (T9–T11). SNA in this preparation was strongly modulated by inspiratory activity. Single-shot electrical stimulation of the ipsilateral rostral ventrolateral medulla (RVLM) induced a transient increase of SNA. Bath application of angiotensin II induced an increase of SNA, and local ipsilateral microinjection of angiotensin II to the RVLM induced a transient increase of SNA. This preparation allows analysis of the central control of the SNA in vitro.

Keywords

Sympathetic nerve activity Respiratory activity In vitro Angiotensin II Newborn rat 

Notes

Author contributions

YO, KI, and HO designed and performed the electrophysiological recordings, analyzed the data, and wrote the manuscript. YM, TO and MI helped to draft the manuscript. All authors approved the final version of the manuscript.

Complaince with ethical standards

Funding

This work was supported by Grants-in Aid for Scientific Research (KAKENHI: 15K01835, 25461070).

Conflict of interest

The authors declare that they have no conflict of interest.

References

  1. 1.
    Suzue T (1984) Respiratory rhythm generation in the in vitro brain stem-spinal cord preparation of the neonatal rat. J Physiol 354:173–183CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Ballanyi K, Onimaru H, Homma I (1999) Respiratory network function in the isolated brainstem-spinal cord of newborn rats. Prog Neurobiol 59:583–634CrossRefPubMedGoogle Scholar
  3. 3.
    Su CK (1999) Rhythmic sympathetic nerve discharges in an in vitro neonatal rat brain stem-spinal cord preparation. J Appl Physiol (1985) 87:1066–1074Google Scholar
  4. 4.
    Deuchars SA, Spyer KM, Brooks PA, Gilbey MP (1995) A study of sympathetic preganglionic neuronal activity in a neonatal rat brainstem-spinal cord preparation. J Auton Nerv Syst 52:51–63CrossRefPubMedGoogle Scholar
  5. 5.
    Minoura Y, Onimaru H, Iigaya K, Homma I, Kobayashi Y (2009) Electrophysiological responses of sympathetic preganglionic neurons to ANG II and aldosterone. Am J Physiol Regul Integr Comp Physiol 297:R699–R706CrossRefPubMedGoogle Scholar
  6. 6.
    Oshima N, Kumagai H, Onimaru H, Kawai A, Pilowsky PM, Iigaya K, Takimoto C, Hayashi K, Saruta T, Itoh H (2008) Monosynaptic excitatory connection from the rostral ventrolateral medulla to sympathetic preganglionic neurons revealed by simultaneous recordings. Hypertens Res 31:1445–1454CrossRefPubMedGoogle Scholar
  7. 7.
    Tanabe A, Onimaru H, Suzuki H, Takeyama Y, Homma I (2012) Effects of corticotropin-releasing factor on intermediolateral cell column neurons of newborn rats. Auton Neurosci 171:36–40CrossRefPubMedGoogle Scholar
  8. 8.
    Onimaru H, Homma I (1992) Whole cell recordings from respiratory neurons in the medulla of brainstem-spinal cord preparations isolated from newborn rats. Pflugers Arch 420:399–406CrossRefPubMedGoogle Scholar
  9. 9.
    Baekey DM, Dick TE, Paton JF (2008) Pontomedullary transection attenuates central respiratory modulation of sympathetic discharge, heart rate and the baroreceptor reflex in the in situ rat preparation. Exp Physiol 93:803–816CrossRefPubMedGoogle Scholar
  10. 10.
    Iigaya K, Okazaki S, Minoura Y, Onimaru H (2017) Interaction between novel oscillation within the ventromedial hypothalamus and the sympathetic nervous system. Neuroscience 343:213–221CrossRefPubMedGoogle Scholar
  11. 11.
    Chen HK, Su CK (2006) Endogenous activation of nicotinic receptors underlies sympathetic tone generation in neonatal rat spinal cord in vitro. Neuropharmacology 51:1120–1128CrossRefPubMedGoogle Scholar
  12. 12.
    Matsuura T, Kumagai H, Kawai A, Onimaru H, Imai M, Oshima N, Sakata K, Saruta T (2002) Rostral ventrolateral medulla neurons of neonatal Wistar-Kyoto and spontaneously hypertensive rats. Hypertension 40:560–565CrossRefPubMedGoogle Scholar
  13. 13.
    Arata A, Onimaru H, Homma I (1990) Respiration-related neurons in the ventral medulla of newborn rats in vitro. Brain Res Bull 24:599–604CrossRefPubMedGoogle Scholar
  14. 14.
    Hu L, Zhu DN, Yu Z, Wang JQ, Sun ZJ, Yao T (2002) Expression of angiotensin II type 1 (AT(1)) receptor in the rostral ventrolateral medulla in rats. J Appl Physiol (1985) 92:2153–2161CrossRefGoogle Scholar
  15. 15.
    Lewis DI, Coote JH (1993) Angiotensin II in the spinal cord of the rat and its sympatho-excitatory effects. Brain Res 614:1–9CrossRefPubMedGoogle Scholar
  16. 16.
    Sasaki S, Dampney RA (1990) Tonic cardiovascular effects of angiotensin II in the ventrolateral medulla. Hypertension 15:274–283CrossRefPubMedGoogle Scholar
  17. 17.
    Ahmad Z, Milligan CJ, Paton JF, Deuchars J (2003) Angiotensin type 1 receptor immunoreactivity in the thoracic spinal cord. Brain Res 985:21–31CrossRefPubMedGoogle Scholar
  18. 18.
    Dendorfer A, Thornagel A, Raasch W, Grisk O, Tempel K, Dominiak P (2002) Angiotensin II induces catecholamine release by direct ganglionic excitation. Hypertension 40:348–354CrossRefPubMedGoogle Scholar
  19. 19.
    Ma X, Abboud FM, Chapleau MW (2001) A novel effect of angiotensin on renal sympathetic nerve activity in mice. J Hypertens 19:609–618CrossRefPubMedGoogle Scholar
  20. 20.
    Ma X, Sigmund CD, Hingtgen SD, Tian X, Davisson RL, Abboud FM, Chapleau MW (2004) Ganglionic action of angiotensin contributes to sympathetic activity in renin-angiotensinogen transgenic mice. Hypertension 43:312–316CrossRefPubMedGoogle Scholar
  21. 21.
    Dick TE, Morris KF (2004) Quantitative analysis of cardiovascular modulation in respiratory neural activity. J Physiol 556:959–970CrossRefPubMedPubMedCentralGoogle Scholar
  22. 22.
    Moraes DJ, da Silva MP, Bonagamba LG, Mecawi AS, Zoccal DB, Antunes-Rodrigues J, Varanda WA, Machado BH (2017) Electrophysiological properties of rostral ventrolateral medulla presympathetic neurons modulated by the respiratory network in rats. J Neurosci 33:19223–19237CrossRefGoogle Scholar
  23. 23.
    Sakata K, Kumagai H, Osaka M, Onami T, Matsuura T, Imai M, Saruta T (2002) Potentiated sympathetic nervous and renin–angiotensin systems reduce nonlinear correlation between sympathetic activity and blood pressure in conscious spontaneously hypertensive rats. Circulation 106:620–625CrossRefPubMedGoogle Scholar
  24. 24.
    Matsuura T, Kumagai H, Onimaru H, Kawai A, Iigaya K, Onami T, Sakata K, Oshima N, Sugaya T, Saruta T (2005) Electrophysiological properties of rostral ventrolateral medulla neurons in angiotensin II 1a receptor knockout mice. Hypertension 46:349–354CrossRefPubMedGoogle Scholar

Copyright information

© The Physiological Society of Japan and Springer Japan KK 2017

Authors and Affiliations

  • Yuji Oyama
    • 1
    • 4
  • Kamon Iigaya
    • 2
  • Yoshino Minoura
    • 3
  • Toshitaka Okabe
    • 4
  • Masahiko Izumizaki
    • 1
  • Hiroshi Onimaru
    • 1
    Email author
  1. 1.Department of PhysiologyShowa University School of MedicineTokyoJapan
  2. 2.Department of Internal MedicineHiratsuka City HospitalHiratsukaJapan
  3. 3.Division of Cardiology, Department of MedicineShowa University School of MedicineTokyoJapan
  4. 4.Division of Cardiology and Cardiac Catheterization LaboratoriesShowa University Northern Yokohama HospitalYokohamaJapan

Personalised recommendations