...Gunnar Ronquist; Goran Frithz Arachidonic and oleic acids, opposite to stearic and palmitic acids, at concentrations near 10 ––5 mol/l markedly inhibited Zn 2+ -dependent ATPase in human prostasome membranes. Arachidonic acid was somewhat more potent as inhibitor than oleic acid and the involvement...

...Ingmar Olsson; Gunnar Ronquist Lactate dehydrogenase (LD, EC 1.1.1.27) activity was determined in serum, seminal plasma and prostasomes from normozoospermic and azoospermic (due to vasectomy) men. A 10-fold higher activity was noted in seminal plasma as compared with serum. LD activity was enriched...

...Mats Lindahl; Christer Tagesson; Gunnar Ronquist Phospholipase A 2 (PLA 2 ) activity was measured and partially characterized in prostasomes isolated from human seminal plasma. The results show high PLA 2 activity in seminal plasma with a threefold enrichment in the isolated prostasomes. Highest...

...Gunnar Ronquist A stimulation by zinc ions of the hydrolysis of ATP by prostasomes prepared from human semen has been observed. Stimulation was maximal at a Zn 2+ /ATP stoichiometry of 0.5/l, and increasing this ratio resulted in a gradual decrease in ATPase activity. The pH optimum was 6.0...

...Gunnar Ronquist; Göran Frithz; Åke Jansson Seminal plasma from 22 men attending an infertility clinic was subjected to preparative ultracentrifu-gation for 2 h at 105,000 g. The pelleted material as well as the supernatant thus obtained were investigated with regard to prostasome membrane-linked...