Search Results

You are looking at 1 - 2 of 2 items for

  • Author: E. A. MUSTILL x
Clear All Modify Search
Free access

J. C. BOURSNELL and E. A. MUSTILL

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

Free access

T. K. ROBERTS, J. C. BOURSNELL, S. E. WINSOR and E. A. MUSTILL

Summary.

The temperature-dependent opalescence caused by the presence of a zinc-precipitable protein (ZPP) in boar seminal plasma has been shown to be pH-dependent.

The considerable pH increase to which boar seminal plasma is subject on exposure to air is attributed to loss of CO2 from a system with a notable paucity of titratable groups in the physiological range pH 7 to 9. This markedly affects the temperature-dependent opalescence.

The ZPP has been purified and the temperature-dependent opalescence of this material can be demonstrated only within a narrow range of zinc concentration in the absence of other possible ligands present in whole seminal plasma.