Suppression of glomus cell K + conductance by 4-aminopyridine is not related to [Ca 2+] i, dopamine release and chemosensory discharge from carotid body
Arijit Roy, Charmaine Rozanov, Donald G Buerk, Anil Mokashi and Sukhamay Lahiri
Carotid body Dopamine Hypoxia Intracellular calcium K +–O 2 current Perfusion
The hypothesis that suppression of O
2-sensitive K
+ current is the initial event in hypoxic chemotransduction in the carotid body glomus cells was tested by using 4-aminopyridine (4-AP), a known suppressant of K
+ current, on intracellular [Ca
2+]
i
, dopamine secretion and chemosensory discharge in cat carotid body (CB). In vitro experiments were performed with superfused–perfused cat CBs, measuring chemosensory discharge, monitoring dopamine release by microsensors without and with 4-AP (0.2, 1.0 and 2.0 mM in CO
2-HCO
3
- buffer) and recording [Ca
2+]
i
by ratio fluorometry in isolated cat and rat glomus cells. 4-AP decreased the chemosensory activities in normoxia but remained the same in hypoxia and in flow interruption. It decreased the tissue dopamine release in normoxia, and showed an additional inhibition with hypoxia. Also, 4-AP did not evoke any rise in [Ca
2+]
i
in glomus cells either during normoxia and hypoxia, although hypoxia stimulated it. Thus, the lack of stimulatory effect on chemosensory discharge, inhibition of dopamine release and unaltered [Ca
2+]
i
by 4-AP are not consistent with the implied meaning of the suppressant effect on K
+ current of glomus cells.
Suppression of glomus cell K + conductance by 4-aminopyridine is not related to [Ca 2+] i, dopamine release and chemosensory discharge from carotid body
Creators
Arijit Roy - University of Pennsylvania
Charmaine Rozanov - University of Pennsylvania
Donald G Buerk - University of Pennsylvania
Anil Mokashi - University of Pennsylvania
Sukhamay Lahiri - University of Pennsylvania
Publication Details
Brain research, v 785(2), pp 228-235
Publisher
Elsevier
Resource Type
Journal article
Language
English
Academic Unit
School of Biomedical Engineering, Science, and Health Systems
Web of Science ID
WOS:000073273800005
Scopus ID
2-s2.0-0032473589
Other Identifier
991019231753204721
UN Sustainable Development Goals (SDGs)
This publication has contributed to the advancement of the following goals:
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool: