Nerve growth factor and brain-derived neurotrophic factor attenuate angiotensin-II-induced facilitation of calcium channels in acutely dissociated nucleus tractus solitarii neurons of the rat.
OBJECTIVE
Neurotrophins, such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), promote neuronal development and neuronal survival, but their mechanisms remain controversial. This study aimed to investigate the hypothesis that NGF and BDNF interfere with angiotensin-II- and glutamate-induced facilitation of voltage-dependent Ca(2+) channels (VDCCs) in nucleus tractus solitarius (NTS) neurons.


METHODS
The profile of NGF and BDNF actions in acutely dissociated rat NTS was studied using the whole-cell configuration of the patch-clamp technique.


RESULTS
Pretreatment with NGF and BDNF attenuated angiotensin-II-induced facilitation of VDCCs, but did not attenuate glutamate-induced facilitation of the L-type VDCC current in NTS neurons. NGF-induced attenuation was antagonised by pretreatment with a tyrosine kinase A (TrkA) receptor antagonist K-252a.


CONCLUSIONS
NGF attenuated angiotensin-II-induced facilitation of L-type VDCCs mediated by TrkA receptors in NTS neurons.
Endoh
Takayuki
T
Oral Health Science Center HRC7, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba 261-8502, Japan. tendoh@tdc.ac.jp
Sato
Daisuke
D
Wada
Yoshiyuki
Y
Ishihara
Kazuyuki
K
Hashimoto
Sadamitsu
S
Yoshinari
Masao
M
Matsuzaka
Kenichi
K
Tazaki
Masakazu
M
Inoue
Takashi
T
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology* / Q000502:physiology; D015220:Calcium Channels / Q000187:drug effects* / Q000502:physiology; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D020932:Nerve Growth Factor / Q000494:pharmacology* / Q000502:physiology; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D017552:Solitary Nucleus / Q000187:drug effects* / Q000502:physiology; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D019208:Brain-Derived Neurotrophic Factor; D015220:Calcium Channels; D014662:Vasoconstrictor Agents; D000804:Angiotensin II; D020932:Nerve Growth Factor