Ca2+-dependent phosphatase and ATPase activities in eel gill plasma membranes--I. Identification of Ca2+-activated ATPase activities with non-specific phosphatase activities.

Ca2+-DEPENDENT PHOSPHATASE AND ATPase ACTIVITIES IN EEL GILL PLASMA MEMBRANES—I. IDENTIFICATION OF Ca2+-ACTIVATED ATPase ACTIVITIES WITH NON-SPECIFIC PHOSPHATASE ACTIVITIES*

1. The characteristics of Ca2+-activated ATPase activities previously often postulated as components for the calcium transporting system in fish gills do not fulfil the requirements of a transport Ca: '-ATPase. 2. The chelation of Ca;~or Mg:~-ions is a prerequisite for the adenosinephosphate esters to serve as substrate for gill plasma membrane phosphatases. 3. Ca2+-activated ATP hydrolysis res...

Ca2+-DEPENDENT PHOSPHATASE AND ATPase ACTIVITIES IN EEL GILL PLASMA MEMBRANES—I. IDENTIFICATION OF Ca2+-ACTIVATED ATPase ACTIVITIES WITH NON-SPECIFIC PHOSPHATASE ACTIVITIES*

1. The characteristics of Ca2+-activated ATPase activities previously often postulated as components for the calcium transporting system in fish gills do not fulfil the requirements of a transport Ca: '-ATPase. 2. The chelation of Ca;~or Mg:~-ions is a prerequisite for the adenosinephosphate esters to serve as substrate for gill plasma membrane phosphatases. 3. Ca2+-activated ATP hydrolysis res...

Ca2+-DEPENDENT PHOSPHATASE AND ATPase ACTIVITIES IN EEL GILL PLASMA MEMBRANES—I. IDENTIFICATION OF Ca2+-ACTIVATED ATPase ACTIVITIES WITH NON-SPECIFIC PHOSPHATASE ACTIVITIES*

1. The characteristics of Ca2+-activated ATPase activities previously often postulated as components for the calcium transporting system in fish gills do not fulfil the requirements of a transport Ca: '-ATPase. 2. The chelation of Ca;~or Mg:~-ions is a prerequisite for the adenosinephosphate esters to serve as substrate for gill plasma membrane phosphatases. 3. Ca2+-activated ATP hydrolysis res...

Ca2+-DEPENDENT PHOSPHATASE AND ATPase ACTIVITIES IN EEL GILL PLASMA MEMBRANES—I. IDENTIFICATION OF Ca2+-ACTIVATED ATPase ACTIVITIES WITH NON-SPECIFIC PHOSPHATASE ACTIVITIES*

1. The characteristics of Ca2+-activated ATPase activities previously often postulated as components for the calcium transporting system in fish gills do not fulfil the requirements of a transport Ca: '-ATPase. 2. The chelation of Ca;~or Mg:~-ions is a prerequisite for the adenosinephosphate esters to serve as substrate for gill plasma membrane phosphatases. 3. Ca2+-activated ATP hydrolysis res...

Ca2+-DEPEN DENT PHOSPHATASE AN D Ca2+-DEPENDENT ATPase ACTIVITIES IN PLASMA MEMBRANES OF EEL GILL EPITHELIUM— III. STIMULATION OF BRANCHIAL HIGH-AFFINITY Ca2+-ATPase ACTIVITY DURING PROLACTIN-INDUCED HYPERCALCEMIA IN AMERICAN EELS