A.R.C. Unit of Reproductive Physiology and Biochemistry, Cambridge
(Received 20th September 1974)
Westmoreland, First & Hoekstra (1967) demonstrated absorption of seminal zinc by boar spermatozoa on cooling. Partial association of this zinc with the seminal proteins has been studied by Boursnell, Briggs, Lavon & Butler (1973a, b). More recently, Boursnell & Roberts (1974), Roberts, Boursnell & Brown (1974) and Roberts, Boursnell, Winsor & Mustill (1974) reported a seminal zinc-protein which was absorbed in part by spermatozoa from cooled semen.
This paper begins a study of the conditions which control the zinc and zinc-protein absorbancies. Small-scale methods were devised which speeded the analyses and permitted triplicate determinations in all cases. Routine weighings, adopted to ensure quantitative retrieval of the centrifuged spermatozoa, revealed unsuspected weight changes in the sperm pellet centrifuged from cold semen. The cause of this problem was sought.
The method of centrifuging (5 min, room temperature, 3000 g) spermatozoa