ABSTRACT
The effects of low temperatures on living organisms have fascinated people for centuries. Almost 320 years ago, Robert Boyle, as cited by Parkes (1957), published a monograph titled New Experiments and Observations Touching Cold. This was the same Robert Boyle who formulated the principle that now bears his name: that the volume of an ideal gas at constant temperature varies inversely with the pressure exerted on it. The relevance of Boyle’s Law to analysis of cellular water content and low-temperature biology can hardly be exaggerated. More than 60 years ago, Lucké (1940) presented a graphical representation of the osmotic response of the eggs of marine invertebrates when they were suspended in hypertonic solutions of impermeant and permeating solutes, including shrinkage and swelling of the eggs in ethylene glycol. Even very recently, measurements relating the volume of cells subjected to hypertonic solutions are presented as Boylevan’t Hoff graphs in which the volume of a cell is plotted as a function of the reciprocal of osmotic pressure of the solution in which the cell is suspended. An example is shown in Figure 11.1, for mouse zygotes, redrawn from data described by Oda et al. (1992). This example shows that the nonosmotic volume of mouse zygotes derived from the point on the plot at which the solution is
infinitely concentrated, where 1/∞ = 0, is approximately 20%. The corollary of this fact is that about 80% of the volume of mouse zygotes, like that of most mammalian oocytes and embryos, is water. It is also notable that Jacobus van’t Hoff, the second name assigned to such graphs, was awarded the first Nobel Prize in Chemistry in 1901 for the “extraordinary services he has rendered by the discovery of the laws of chemical dynamics and osmotic pressure in solutions,” as his Nobel citation read. Other recent examples of Boyle-van’t Hoff plots as part of cryobiological analysis have been published for mouse spermatozoa (Willoughby et al., 1996), for uterine tissue (Devireddy et al., 2001), and for rhesus monkey oocytes (Songsasen et al., 2002).
