PMID- 7582467
OWN - NLM
STAT- MEDLINE
DCOM- 19951127
LR  - 20190512
IS  - 0007-1188 (Print)
IS  - 0007-1188 (Linking)
VI  - 115
IP  - 3
DP  - 1995 Jun
TI  - All-or-none augmentation of Ca2+ sensitivity in alpha-toxin-permeabilized single 
      smooth muscle cells from guinea-pig taenia caecum.
PG  - 522-6
AB  - 1. Isolated smooth muscle cells from guinea-pig taenia caecum were permeabilized 
      by use of Staphylococcus aureus alpha-toxin, and the sarcoplasmic reticulum Ca2+ 
      store was depleted by exposure to 0.1 microM A23187. 2. Shortening of 
      alpha-toxin-permeabilized single smooth muscle cells was induced by increasing 
      free Ca2+ but was not induced by 0.2 microM free Ca2+. 3. Shortening of the 
      permeabilized cells was caused by application of acetylcholine (ACh) with free 
      Ca2+ concentration held at 0.2 microM. Permeabilized smooth muscle cells 
      responded to 0.3 microM or 1 microM ACh with 0.2 microM Ca2+ with maximal 
      shortening. The concentration-response relationship to ACh had a very steep slope 
      and the cell shortening appeared to be an all-or-none response rather than a 
      graded response, as was the shortening of intact cells to ACh. 4. The shortening 
      of permeabilized cells was also induced by application of guanosine 
      5'-triphosphate (GTP) with 0.2 microM free Ca2+, showing an all-or-none response. 
      The threshold concentration of GTP that induced an all-or-none response was 
      between 10 microM and 30 microM. 5. These results suggest that Ca2+ sensitivity 
      is augmented by stimulation of the muscarinic receptor or GTP-binding protein(s) 
      in an all-or-none manner. It seems probable that this contributes to the 
      all-or-none response to ACh in intact smooth muscle cells.
FAU - Mita, M
AU  - Mita M
AD  - Department of Pharmacology, Meiji College of Pharmacy, Tokyo, Japan.
FAU - Hashimoto, T
AU  - Hashimoto T
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Br J Pharmacol
JT  - British journal of pharmacology
JID - 7502536
RN  - 0 (Bacterial Toxins)
RN  - 0 (Hemolysin Proteins)
RN  - 0 (Ionophores)
RN  - 0 (Receptors, Muscarinic)
RN  - 0 (staphylococcal alpha-toxin)
RN  - 37H9VM9WZL (Calcimycin)
RN  - 86-01-1 (Guanosine Triphosphate)
RN  - EC 3.6.1.- (GTP-Binding Proteins)
RN  - N9YNS0M02X (Acetylcholine)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Acetylcholine/pharmacology
MH  - Animals
MH  - Bacterial Toxins/*toxicity
MH  - Calcimycin/pharmacology
MH  - Calcium/*metabolism/pharmacology
MH  - Cecum/cytology/*drug effects
MH  - Cell Membrane Permeability/drug effects
MH  - Cell Size/drug effects
MH  - Cells, Cultured
MH  - GTP-Binding Proteins/drug effects/metabolism
MH  - Guanosine Triphosphate/pharmacology
MH  - Guinea Pigs
MH  - Hemolysin Proteins/*toxicity
MH  - Ionophores/pharmacology
MH  - Microscopy, Phase-Contrast
MH  - Muscle Contraction/drug effects
MH  - Muscle, Smooth/cytology/*drug effects
MH  - Receptors, Muscarinic/drug effects/metabolism
MH  - Sarcoplasmic Reticulum/drug effects/metabolism
MH  - *Staphylococcus aureus
PMC - PMC1908411
EDAT- 1995/06/01 00:00
MHDA- 1995/06/01 00:01
PMCR- 1996/06/01
CRDT- 1995/06/01 00:00
PHST- 1995/06/01 00:00 [pubmed]
PHST- 1995/06/01 00:01 [medline]
PHST- 1995/06/01 00:00 [entrez]
PHST- 1996/06/01 00:00 [pmc-release]
AID - 10.1111/j.1476-5381.1995.tb16365.x [doi]
PST - ppublish
SO  - Br J Pharmacol. 1995 Jun;115(3):522-6. doi: 10.1111/j.1476-5381.1995.tb16365.x.