Leucyl naphthylamidase activity in pigeon and toad testes under various experimental conditions

The activity pattern and functional significance of leucyl naphthylamidase (LNase) in the pigeon testis under different hormonal and photoperiod conditions as well as in the testes of short- and long-term HCG-treated toads have been studied histochemically. In both the species, the enzyme activity was present in the maturing spermatids and those embedded in the Sertoli cell components, the mature spermatozoa released in the lumen being devoid of any LNase activity. In pigeon, the stimulation of spermatogenic process was associated with enhanced activity of the enzyme, whereas arrest of spermatogenesis showed little or no activity. In toad, short-term HCG treatment caused mild stimulation of spermiation resulting in sperm release from the Sertoli cells and this was accompanied by moderate decrease in LNase activity. The long-term HCG treatment produced an enhanced stimulation of spermiogenesis and spermiation processes resulting in almost total disappearance of LNase activity. The above observations suggest that the enzyme in the testes of both species is related to spermiogenesis and/or spermiation events of spermatogenesis.