Use of BMDP statistical package to generate maximum liklihood estimates for single channel data.
Patch clamping and single channel recording are valuable techniques for studying ion channel function. One difficulty associated with single channel recording is analysis of large numbers of opening events and determination of the distribution of dwell times in a given state. This paper reports on use of a standard statistical package, BMDP, for obtaining maximum likelihood estimates of time constants and amplitudes for single or double exponential distributions. The program operates directly on observed dwell times, not on binned values in a histogram. In order to verify its accuracy, the software was challenged with stimulated test data. Estimates for time constants and amplitudes were correct to within a few percent. The program did have difficulty, however, in resolving 2 components of a double exponential distribution if the separation between the components was less than a factor of 2-2.5. In such cases it was often difficult to decide whether a single or double exponential function was more appropriate to describe the data.
Wachtel
R E
RE
Department of Anesthesia, Veterans Administration Medical Center, Iowa City, IA 52240.
D007473:Ion Channels / Q000502:physiology*; D012984:Software; D013223:Statistics as Topic
D007473:Ion Channels