Single cell physiology

Kotlikojf Sometimes we see a substantial lag other times it is shorter than 500 ms. I don t know the answer. Because of the number of differences between a single-cell stretch experiment and real physiology, I don t know whether this explains things such as pressure-induced vascular tone. One thing that will be informative here is if the RyR2 knockouts are viable and we can look at them. 

Bolton If you are saying that single cells are not a good paradigm for whole tissues, that may be true they have been damaged in the preparation process. But, equally when you take the preparation out of the body and put it in a physiological salt solution, it still isn t physiological. 

The measurements can be made at various levels from that of subcellular organelles, to single cells, cell populations and even tissues. They can be made on either fixed cells or on live cells that are incubated under physiological conditions. They can be made in end point assays or kinetically, in real time. Compared to previous manual methods, automation provides a marked improvement in the capacity for sample and experiment throughput, the precision of measurement and in the sheer number and diversity of parameters measureable for an experiment. Consolidation of the technical capabilities allo vs unparalleled vhthin-experiment, cross-comparisons of biochemical, morphological and functional parameters. Compared to flo v cytometry it offers substantially greater analytic capability for morphometric and kinetic parameters, although for substantially lo ver numbers of cells. 

As pointed out before when discussing structured models, physiological functions like the single cell growth rate r(m, S), cellular division rate T(m, S), and cell mass partition function p(m, m, S) are difficult to measure and this adds to the complexity of using the model. The mathematical complexity is also a limitation for optimization and control purposes that demand online measurements and calculations. 

Patterns Generated by the Outer Membrane. As in the single cell case, the outer membrane itself can generate electro-physiological patterns, even in the absence of reactions in the cell mass, R = 0. Such surface induced patterns were first discussed in the context of reaction-diffusion patterns in Ref. 

Fig. 14.45. Amperometric recordings from a single canine pancreatic (3-cell bathed in Ca2+-free physiological buffer. Bars indicate the application of solution from a micropipette. In the trace on the left, the solution applied was Ca2+-free physiological buffer with 64 mM K+. (Reprinted from Lan Huang and Robert Kennedy, Exploring Single-Cell Dynamics Using Chemically-Modified Microelectrodes, in Trends in Analytical Chemistry, Vol. 14, p. 160, Fig. 3, copyright 1995, with permission from Elsevier Science.)...

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