A Met-enkephalin releaser (kyotorphin)-induced release of plasma membrane-bound Ca2+ from rat brain synaptosomes.
The neuropeptide kyotorphin (Tyr-Arg) released 45Ca2+ from synaptosomal membrane preparations of the rat lower brainstem. This dipeptide also decreased plasma membrane-bound Ca2+ ([Ca2+]m), determined using chlorotetracycline, in the slice and synaptosome of the rat lower brainstem. Taken together with other data indicating that kyotorphin induces an increase in synaptosomal intracellular Ca2+ ([Ca2+]i) in a Ca2+ channel-independent manner, it is suggested that kyotorphin may mobilize the [Ca2+]m and thus increase the [Ca2+]i in the nerve terminals of the rat lower brainstem.
Ueda
H
H
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Fukushima
N
N
Yoshihara
Y
Y
Takagi
H
H
D000700:Analgesics / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000493:pharmacokinetics*; D004723:Endorphins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004744:Enkephalin, Methionine / Q000378:metabolism* / Q000502:physiology; D066298:In Vitro Techniques; D008526:Medulla Oblongata / Q000187:drug effects / Q000378:metabolism*; D011149:Pons / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
D000700:Analgesics; D004723:Endorphins; C019448:kyotorphin; D004744:Enkephalin, Methionine; D002118:Calcium