Understanding chemistry of spermatozoa using NMR

In recent years, NMR has found wide applications, on one end to study the s tructure of molecules and on the other, to study intact body organs such as brain or heart. In between these two extremes is another fascinating branc h of science, namely, the study of chemistry of intact cellular systems. Wh ite dedicated instruments for this type of work are not available, it is po ssible to use high field high resolution NMR spectrometers meant for molecu lar studies (e.g. a 300-500 MHz instrument) to obtain chemical and biologic al information on living cells. We have studied the chemistry of one of the important cellular systems, spermatozoa, using NMR. Spermatozoa play a key role in reproductive biology. Using techniques such as HSQC, it has been p ossible to obtain information on the H-1 end C-13 NMR features of such cell s. We have been able to detect a number of molecules in these sperm cells, which had evaded detection by conventional chemical tools. It has been poss ible to follow chemical pathways and kinetics of metabolism using conventio nal C-13 NMR. P-31 NMR provides valuable information on the energetics and pH profiles. Some of these studies have helped us to know how such cells ca n be activated or deactivated. For example, arginine deficiency is known to cause diseases such as oligospermia and asthenospermia. NMR experiments ha ve established that the glycolysis and fructolysis of spermatozoa is activa ted by arginine. Arginine also increases synthesis of ATP, which is essenti al for sperm motility. The chemical information thus obtained has major bio logical implication for storage, activation and control of spermatozoa.