Action Potentials|Animals|Biophysical Phenomena|Calcium|Coloring Agents|Computer Simulation|Cytoplasm|Endoplasmic Reticulum|Ganglia, Spinal|Humans|Inositol 1,4,5-Trisphosphate Receptors|Membrane Potentials|Mitochondria|Neurons|Plasma Membrane Calcium-Transporting ATPases|Potassium Channels, Calcium-Activated|Ryanodine Receptor Calcium Release Channel|Sarcoplasmic Reticulum Calcium-Transporting ATPases|Sodium Channels|Urinary Bladder