Calcium and the Secretory Process

1 General Concepts.- Biological Importance of Calcium.- Calcium Distribution and Tissue Concentrations.- Redistribution of Calcium during Stimulation.- Regulation of Cell Calcium.- Binding.- Exchange Diffusion.- Active Transport.- Calcium and Membrane Permeability.- Ion Antagonisms.- Summary and Conclusions.- 2 Action of Calcium on the Secretory Process.- Cholinergic Neurons, Chromaffin Cells, and Neurosecretory Cells.- Historical Background.- Electrophysiological Events Associated with Secretion.- Role of Monovalent Cations.- Multivalent Cations.- Conclusions.- Other Neuronal Systems.- Excitatory and Inhibitory Synapses.- Adrenergic Synapses.- Release of Other Biogenic Amines.- Histamine.- 5-Hydroxytryptamine.- Release of Water and Protein.- Salivary Gland.- Exocrine Pancreas.- Granular Proteins from Leukocytes.- Gastric Secretion.- Endocrine Secretory Systems.- Insulin Release.- Corticosteroids.- Thyroid Hormone..- Pituitary Trophic Hormones.- Parathyroid Hormone and Calcitonin.- Conclusions.- 3 Nature of the Role of Calcium in Secretion.- Mechanism of Secretion.- Mode of Calcium Action.- Physical Theories.- Chemical Theories.- Microtubular-Microfilamentous System.- Cytoplasmic Motility.- Conclusions.- 4 Role of Cyclic AMP in the Secretory Process.- Effects of Exogenous Cyclic Nucleotide.- Phosphodiesterase Inhibition.- Measurement of Cyclic AMP Levels.- Interaction between Calcium and Cyclic AMP.- Prostaglandins.- Conclusions.- References.