ANGIOTENSIN-II STIMULATES SPERM MOTILITY

The physiological factors which induce and maintain mammalian sperm ma turation and motility generally remain unclear, although several agent s are known to be involved. We recently described the application of i mmunocytochemical and immunoblotting methods to identify the angiotens in II type 1 (AT1) receptor in the tails of ejaculated rat and human s perm, and gave evidence to show that angiotensin II may promote sperm motility. These data are extended here by the application of a compute rised sperm tracking system (the Hobson Sperm Tracker) to demonstrate that AII has actions on specific motility parameters, including curvil inear velocity, straight line velocity, and amplitude of lateral head movement. Since local tissue renin-angiotensin systems are present in both male and female tracts, the data suggest that angiotensin II has a role in the maintenance of sperm function and fertility.