Synaptic activity-related classical protein kinase C isoform localization in the adult rat neuromuscular synapse.
Protein kinase C (PKC) is essential for signal transduction in a variety of cells, including neurons and myocytes, and is involved in both acetylcholine release and muscle fiber contraction. Here, we demonstrate that the increases in synaptic activity by nerve stimulation couple PKC to transmitter release in the rat neuromuscular junction and increase the level of alpha, betaI, and betaII isoforms in the membrane when muscle contraction follows the stimulation. The phosphorylation activity of these classical PKCs also increases. It seems that the muscle has to contract in order to maintain or increase classical PKCs in the membrane. We use immunohistochemistry to show that PKCalpha and PKCbetaI were located in the nerve terminals, whereas PKCalpha and PKCbetaII were located in the postsynaptic and the Schwann cells. Stimulation and contraction do not change these cellular distributions, but our results show that the localization of classical PKC isoforms in the membrane is affected by synaptic activity.
Besalduch
Núria
N
Unitat d'Histologia i Neurobiologia (UHN), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain.
Tomàs
Marta
M
Santafé
Manel M
MM
Garcia
Neus
N
Tomàs
Josep
J
Lanuza
Maria Angel
MA
D000818:Animals; D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D004558:Electric Stimulation; D004594:Electrophysiology; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D018613:Microscopy, Confocal; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology; D009469:Neuromuscular Junction / Q000201:enzymology* / Q000648:ultrastructure; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012583:Schwann Cells / Q000201:enzymology / Q000648:ultrastructure; D013569:Synapses / Q000201:enzymology* / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D007527:Isoenzymes; D011493:Protein Kinase C