For instance, in plant tissue, polysaccharides such as starch and cellulose are known to exhibit strong SHG responses.1- 2 In animal tissue, type I collagen and type II myosin, which are two of the most abundant structural proteins, are both dominant second harmonophores and have been extensively discussed in recent literatures.3- 5 The glial fibrillary acidic protein in astroglial filaments and t