Voltage-dependent calcium channel subtypes controlling somatic substance P release in the peripheral nervous system.
1. Isolated rat dorsal root ganglia (DRG) neurones support vesicular, non synaptic release of substance P in a depolarisation and Ca2+ dependent manner. 2. In vivo this process may mediate cross-communication between DRG cells in some neuropathological conditions and is therefore a putative area for drug intervention. 3. The authors investigated the voltage-dependent Ca2+ channel (VDCC) subtypes involved in somatic release of substance P. Fresh (< 1 day) cultures of DRG neurones were incubated with high K+ depolarising saline in the presence and absence of subtype selective VDCC blockers. Substance P released into the external media was collected and quantified using a radioimmunoassay. 4. The results show that L-type and N-type, but not P-type, VDCCs play an important role in high K+ evoked substance P release from rat DRG neurones.
Harding
L M
LM
School of Biological and Molecular Sciences, Oxford Brookes University, Headington, UK.
Beadle
D J
DJ
Bermudez
I
I
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects / Q000502:physiology*; D020746:Calcium Channels, L-Type / Q000187:drug effects; D020864:Calcium Channels, N-Type / Q000187:drug effects; D020865:Calcium Channels, P-Type / Q000187:drug effects; D004594:Electrophysiology; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008854:Microscopy, Electron; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D017933:Peripheral Nervous System / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013373:Substance P / Q000378:metabolism*
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D020746:Calcium Channels, L-Type; D020864:Calcium Channels, N-Type; D020865:Calcium Channels, P-Type; D013373:Substance P; D011188:Potassium