Cortical photons in early development of frog eggs: comparative study of photon emission between nuclear division and cytoplasmic fission.

In the study of cell division in the early development of frog eggs, cortical photon emission was investigated by converting small light emission from living cells into digital pulses of potentials and recording the integrals of these pulses (analog method), counting the number of pulses (photon-counting method), and counting the number of integrated pulses (improved photon-counting method). By the analog and improved photon-counting methods, changes in photon emission due to cell division could be clearly detected. The emitted light increased about 5.10(-19)W at the start of a cleavage furrow. Rapid changes in chemical reactions causing photon emission were compared during nuclear division and cytoplasmic phases. This emission occurred mainly in cytoplasmic fission, the rate being greater than in nuclear division by a factor of about 2.9. Chemical reaction rates were shown to differ according to bulk emission, thus indicating the mechanisms for the reactions to also differ.