PMID- 8786642
OWN - NLM
STAT- MEDLINE
DCOM- 19960926
LR  - 20190725
IS  - 0021-5198 (Print)
IS  - 0021-5198 (Linking)
VI  - 69
IP  - 4
DP  - 1995 Dec
TI  - Suppression of capacitative Ca2+ entry by serine/threonine phosphatase inhibitors 
      in rat parotid acinar cells.
PG  - 381-9
AB  - The effects of three serine/threonine protein phosphatase inhibitors, 
      calyculin-A, tautomycin and okadaic acid, on the Ca2+ entry across the plasma 
      membrane was studied in Fura-2-loaded rat parotid acinar cells. These protein 
      phosphatase inhibitors did not affect the peak elevation of cytosolic free Ca2+ 
      concentration ([Ca2+]i) just after stimulation with the muscarinic agonist 
      carbachol (CCh), but they suppressed the sustained increase in [Ca2+]i. In the 
      absence of extracellular Ca2+, CCh produced a transient increase in [Ca2+]i due 
      to Ca2+ release from intracellular Ca2+ stores, and this increase in [Ca2+]i was 
      unaffected by the phosphatase inhibitors. When Ca2+ was added to the external 
      medium after the transient [Ca2+]i response, the increase in [Ca2+]i in the cells 
      treated with the phosphatase inhibitors was significantly smaller than that in 
      the control cells, indicating that the Ca2+ entry was reduced. Similar 
      suppression of Ca2+ entry by the phosphatase inhibitors was observed when 
      intracellular Ca2+ stores were previously depleted by the microsomal 
      Ca(2+)-ATPase inhibitor thapsigargin (TG). In addition, the phosphatase 
      inhibitors reduced the Mn2+ (Ca2+ surrogate) influx following the addition of CCh 
      or TG. The enhancement of Ca2+ entry by the protein kinase inhibitor 
      staurosporine was significantly attenuated by the phosphatase inhibitors. These 
      results suggest that the phosphatase inhibitors suppressed the Ca2+ entry 
      mechanism activated by depletion of intracellular Ca2+ stores in rat parotid 
      acinar cells. The capacitative Ca2+ entry may be regulated by protein 
      phosphorylation/dephosphorylation.
FAU - Tojyo, Y
AU  - Tojyo Y
AD  - Department of Dental Pharmacology, Health Sciences University of Hokkaido, Japan.
FAU - Tanimura, A
AU  - Tanimura A
FAU - Matsumoto, Y
AU  - Matsumoto Y
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Japan
TA  - Jpn J Pharmacol
JT  - Japanese journal of pharmacology
JID - 2983305R
RN  - 0 (Alkaloids)
RN  - 0 (Antifungal Agents)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Ethers, Cyclic)
RN  - 0 (Pyrans)
RN  - 0 (Spiro Compounds)
RN  - 109946-35-2 (tautomycin)
RN  - 1W21G5Q4N2 (Okadaic Acid)
RN  - 8Y164V895Y (Carbachol)
RN  - EC 3.1.3.2 (Phosphoric Monoester Hydrolases)
RN  - H88EPA0A3N (Staurosporine)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Alkaloids/pharmacology
MH  - Animals
MH  - Antifungal Agents/pharmacology
MH  - Calcium/*metabolism
MH  - Carbachol/pharmacology
MH  - Enzyme Inhibitors/*pharmacology
MH  - Ethers, Cyclic/*pharmacology
MH  - Male
MH  - Okadaic Acid
MH  - Parotid Gland/*drug effects
MH  - Phosphoric Monoester Hydrolases/drug effects
MH  - *Pyrans
MH  - Rats
MH  - Rats, Wistar
MH  - *Spiro Compounds
MH  - Staurosporine
EDAT- 1995/12/01 00:00
MHDA- 1995/12/01 00:01
CRDT- 1995/12/01 00:00
PHST- 1995/12/01 00:00 [pubmed]
PHST- 1995/12/01 00:01 [medline]
PHST- 1995/12/01 00:00 [entrez]
AID - 10.1254/jjp.69.381 [doi]
PST - ppublish
SO  - Jpn J Pharmacol. 1995 Dec;69(4):381-9. doi: 10.1254/jjp.69.381.