ISSN:
1471-4159
Quelle:
Blackwell Publishing Journal Backfiles 1879-2005
Thema:
Medizin
Notizen:
Abstract The effect of a single administration of morphine sulfate (15 mg/kg, s.c. or 30 mg/kg, i.p., 30 min) on Ca2+-stimulated Mg2+-dependent ATPase activity was investigated in synaptosomal plasma membranes (SPM) prepared from rat cortex. Morphine produced a significant decrease in Ca2+,Mg2+-ATPase activity in synaptosomal fractions (SPM 1 + 2) known to contain a high density of opiate receptors and calmodulin-dependent Ca2+,Mg2+-ATPase. However, in another subpopulation (SPM 3) that contains fewer opiate receptors and less enzyme activity, no such decrease in the enzyme activity was observed after the opiate administration. The decrease in Ca2+,Mg2+-ATPase activity seen in SPM 1 + 2 was specifically antagonized by the opiate antagonist naloxone hydrochloride (2 mg/kg, s.c.) when given 15 min before morphine administration. Mg2+-ATP-ase was not altered either by morphine or by a naloxone-morphine combination. These findings give further evidence for the role of intracellular Ca2+ in mediating many of the acute effects of opiates.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1111/j.1471-4159.1986.tb00807.x
