Postsynaptic inhibitory effects of phenothiazines at cholinergic synapses may not involve calmodulin

Z Y Sahaf, S J Publicover

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

Treatment of frog cutaneous-pectoris nerve-muscle preparations with calmidazolium (R 24571), a calmodulin-inhibitor, at concentrations of 2 X 10(-7) mol/l and 5 X 10(-7) mol/l had no discernable effect on MEPP amplitude. 10(-6) mol/l calmidazolium caused a small (10-35%) increase in MEPP amplitude in most preparations. The phenothiazine calmodulin-inhibitor chlorpromazine (5 X 10(-6) mol/l) caused a clear reduction in MEPP amplitude (20%) after 30 min treatment. Similar experiments carried out with chlorpromazine sulphoxide (a derivative of chlorpromazine that is 60 X less potent in inhibition of calmodulin-activated enzymes) produced data that were very similar to those obtained with chlorpromazine. It is concluded that the postsynaptic inhibitory effect of phenothiazines at cholinergic synapses is unlikely to involve calmodulin.
Original languageEnglish
Pages (from-to)454-6
Number of pages3
JournalNaunyn-Schmiedeberg's Archives of Pharmacology
Volume333
Issue number4
Publication statusPublished - Aug 1986

Keywords

  • Parasympathetic Nervous System
  • Animals
  • Synapses
  • Phenothiazines
  • Evoked Potentials
  • Motor Endplate
  • Chlorpromazine
  • Calmodulin
  • Rana temporaria

Fingerprint

Dive into the research topics of 'Postsynaptic inhibitory effects of phenothiazines at cholinergic synapses may not involve calmodulin'. Together they form a unique fingerprint.

Cite this