Date of Award:
Doctor of Philosophy (PhD)
LeGrande C. Ellis
LeGrande C. Ellis
James A. Jessaman
R. P. Sharma
Thomas L. Bahler
The regulation of the contractility and intratesticular pressure of rabbit testes was studied. The effects of, and interactions among, prostaglandins (PGs) E1 and F2α testosterone, acetylcholine, epinephrine and norepinephrine were ascertained both in vitro and in vivo. All of these compounds, except for high concentrations of PGE1 and testosterone, stimulated the testicular capsule to contract. PGE1 at low concentrations potentiated the contractions produced by epinephrine and acetylcholine. Above 10-7M, PGE1 inhibited contractions caused by PGF2α epinephrine or acetylcholine. Testosterone inhibited contractions caused by PGF2α in vitro.
Preinjections of rabbits with the PG synthetase inhibitor, indomethacin, significantly reduced testicular contractility in vivo. A second inhibitor of PG synthetase, 5,8,11,14-eicosatetraynoic acid (TYA), had no such effect. Reserpine failed to alter testicular contractions in vivo. Attempts to stimulate the spermatic nerve electrically using Ag-AgCl electrodes did not alter intratesticular pressure.
Exposing male rabbits to females had no significant effect on testicular contractions in vivo or in vitro. Serum testosterone measurements were made after injections of indomethacin, TVA, reserpine and combinations of indomethacin and PGE1. No significant changes were noted among groups due to large variability.
Intratesticular pressure showed spontaneous, rhythmical fluctuations in some preparations. Intravenous injections of norepinephrine increased overall pressure, whereas isoproterenol decreased it. The inhibition of rhythmical pressure changes after iv infusion of isoproterenol persisted at least half an hour. During this time norepinephrine failed to increase intratesticular pressure.
Hargrove, James L., "Regulation of Rabbit Testicular Capsular Motility: The Interaction of Prostaglandins, Acetylcholine and Sympathomimetic Agents" (1975). All Graduate Theses and Dissertations. 8342.
Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .