Nerve Regulation of Cholangiocyte Functions

2020 ◽  
pp. 199-209 ◽  
Author(s):  
Barbara Barbaro ◽  
Shannon Glaser ◽  
Heather Francis ◽  
Silvia Taffetani ◽  
Marco Marzioni ◽  
...  
Keyword(s):  
Nerve Regulation

Abstract 327: Attenuated Beta-Adrenergic Response in the Tric-a Knock Out Mice

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_2) ◽  
Author(s):  
Yuichi Toyama ◽  
Manabu Yonekura ◽  
Chong Han ◽  
Hirofumi Tomita ◽  
Hiroshi Takeshima ◽  
...  
Keyword(s):  
Heart Rate ◽  
Action Potential ◽  
Sympathetic Nerve ◽  
Calcium Release ◽  
Calcium Influx ◽  
Ryanodine Receptors ◽  
Low Frequency ◽  
Beta Adrenergic ◽  
Knock Out ◽  
Nerve Regulation

Trimeric intracellular cation (TRIC) channels are expressed on the surface of sarcoplasmic reticulum (SR) and regulate calcium release from ryanodine receptors (RyRs). In a previous study, Tric-a knock out (KO) mice showed diminished calcium release from RyRs following increased calcium-influx via L-type calcium channels, which results in enhanced vascular resistance and non-dipper type hypertension. Decreased activation of RyR1 by PKA in skeletal myocytes in Tric-a KO mice is also known. However, physiological importance of TRIC channels on cardiac rhythm formation and its importance on the sympathetic nerve regulation are still obscure. Therefore, we aimed to clarify the effects of Tric-a ablation on cardiac pace making using Tric-a KO mice. We measured systolic blood pressure (SBP) with tail-cuff method, ECG and spontaneous action potential with microelectrode in the Tric-a KO and wild type (WT) mice. Isoproterenol or propranolol was used for sympathetic nerve manipulation. Furthermore, we evaluated heart rate variability (HRV). Tric-a KO mice tended to show limited responses to isoproterenol (0.3 mg/kg) than the WT mice (-27 ± 6 and -32 ± 6 mmHg, n = 10, p =0.70), and to propranolol (4 ± 6 and 13 ± 7 mmHg, n = 5~6, p =0.48). In ECG analysis, ablation of Tric-a gene resulted in significantly decreased heart rate changes to isoproterenol (23 ± 6 and 99 ± 15 bpm, Tric-a KO and WT mice, respectively, n = 9~10, p <0.001). Response to propranolol was also significantly decreased in the Tric-a KO mice (-28 ± 20 and -122 ± 14 bpm, Tric-a KO and WT mice, respectively, n = 9~10, p <0.001). In the action potential recordings, Tric-a KO mice showed significantly decreased sinus rate changes to 1 microM isoproterenol (35 ± 9 and 71 ± 10 bpm, Tric-a KO and WT mice, respectively, n = 6~8, p <0.05). In HRV analysis, low-frequency/high-frequency (LF/HF) ratio tended to be lower in the Tric-a KO mice than the WT mice under the administration of isoproterenol (0.22 ± 0.31 and 0.65 ± 0.16 bpm, Tric-a KO and WT mice, respectively, n = 9~11, p =0.16), suggesting lower sympathetic nerve tonus in the Tric-a KO mice. In conclusion, our data indicates that Tric-a KO mice showed attenuated responses to beta-adrenergic stimulus, which indicates involvement of TRIC-A channels in sympathetic nerve regulation.

scholarly journals Mechanism of autonomic nerve regulation (XIV)

1961 ◽  
Vol 57 (1) ◽  
pp. 9-16
Author(s):  
Kikuji TOKITA ◽  
Ryuta ITO ◽  
Sukeaki NISHIMUTA ◽  
Yoshinori KAWASAKI ◽  
Shoko MIYAZAKI ◽  
...  
Keyword(s):  
Autonomic Nerve ◽  
Nerve Regulation

scholarly journals Mechanism of autonomic nerve regulation (VII)

1959 ◽  
Vol 55 (4) ◽  
pp. 894-908
Author(s):  
Kikuji TOKITA ◽  
Yoshinori KAWASAKI ◽  
Chikukei NOZAWA ◽  
Hirosi HENOMATU ◽  
Tosio NAGAOKA
Keyword(s):  
Autonomic Nerve ◽  
Nerve Regulation

scholarly journals A critical role of sympathetic nerve regulation for the treatment of impaired daily rhythm in hypertensive Dahl rats

2010 ◽  
Vol 33 (10) ◽  
pp. 1060-1065 ◽  
Author(s):  
Jun-ichi Suzuki ◽  
Masahito Ogawa ◽  
Noriko Tamura ◽  
Yasuhiro Maejima ◽  
Kiyoshi Takayama ◽  
...  
Keyword(s):  
Sympathetic Nerve ◽  
Critical Role ◽  
Daily Rhythm ◽  
Nerve Regulation
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