Coding of time-varying hormonal signals in intracellular calcium spike trains.
In a variety of cell types extracellular hormonal stimuli varying in time are transfered across the cell membrane into repetitive spikes of the intracellular calcium concentration ([Ca2+]i). Distinct temporal patterns of [Ca2+]i spikes are capable of regulating the function and structure of target cells. Here, we investigate the ability of transmembrane signaling to encode time-varying hormonal stimulations (bandlimited Gaussian white noise) in a model of receptor-controlled [Ca2+]i oscillations. The encoding of hormonal signals in [Ca2+]i spike trains is quantified by using an information-theoretic approach allowing to estimate the hormonal stimulus from [Ca2+]i spike trains. Our results suggest that intracellular [Ca2+]i spike trains convey faithful information on temporal variations of extracellular hormonal concentrations at scales of 30-200 sec, corresponding to cut-off frequencies between 5 and 30 mHz of the random hormonal stimulation.
Department of Clinical Endocrinology, Medical School Hannover, Germany.
K
K
Prank
C
C
Schöfl
L
L
Läer
M
M
Wagner
A
A
von zur Mühlen
G
G
Brabant
F
F
Gabbiani
D000818:Animals; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000502:physiology*; D004703:Endocrine System / Q000502:physiology*; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D006728:Hormones / Q000502:physiology*; D007700:Kinetics; D008954:Models, Biological; D009475:Neurons, Afferent / Q000502:physiology*; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism
D006728:Hormones; D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate; D010738:Type C Phospholipases; D002118:Calcium