Surgical denervation of porcine ovaries during the middle luteal phase of the oestrous cycle changes their morphology and steroidogenic activity.
Changes in both the morphology and the steroidogenic activity of porcine ovaries denervated surgically on day 12 of the oestrous cycle were studied. Neurectomy of the plexus and the superior ovarian nerves caused a dramatic reduction in the number (or even a disappearance) of dopamine-beta-hydroxylase- and/or neuropeptide tyrosine-immunoreactive nerve terminals. On day 20 of the subsequent oestrous cycle, the number of small follicles increased (P < 0.01) and that of large follicles decreased (P < 0.05) in the denervated ovaries, as compared to the controls. Neurectomy led to a decrease in the level of progesterone (P4; P < 0.001) and androstenedione (A4; P < 0.01) in the fluid from small follicles, A4 (P < 0.001) and testosterone (T; P < 0.05) in the fluid from medium-sized follicles, as well as in the content of all these steroids in the fluid from large-sized follicles (P < 0.001 for P4 and P < 0.05 for A4 and T). Denervation also caused a decrease in the content of A4 (P < 0.01) and T (P < 0.001) in the wall of follicles. Neurectomy resulted in a significant increase in the immunoexpression of cholesterol side-chain cleavage cytochrome P450 in the follicles and a decrease of 33-hydroxysteroid dehydrogenase. After denervation, plasma levels of LH, P4, A4, T, oestrone and oestradiol-17beta were lower (P < 0.05-0.001) on the particular days of the study than in the control group. Our data revealed that the denervation of ovaries during the middle luteal phase of the oestrous cycle in gilts caused distinct changes in both the morphology and the steroidogenic activity of the organ, confirming an important role of the peripheral nervous system in the control of the gonad in this species.
Jana
Barbara
B
Division of Reproductive Endocrinology and Pathophysiology, Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, 10-747 Olsztyn, Tuwima 10, Poland. baja@pan.olsztyn.pl
Dzienis
Anna
A
Wojtkiewicz
Joanna
J
Kaczmarek
Monika
M
Majewski
M
M
D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D000735:Androstenedione / Q000097:blood; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D003714:Denervation / Q000662:veterinary; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism; D004958:Estradiol; D004970:Estrone / Q000097:blood; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D007986:Luteinizing Hormone / Q000097:blood; D009478:Neuropeptide Y / Q000378:metabolism; D009638:Norepinephrine / Q000096:biosynthesis; D006080:Ovarian Follicle / Q000502:physiology; D010053:Ovary / Q000166:cytology / Q000294:innervation* / Q000378:metabolism / Q000601:surgery; D011374:Progesterone / Q000097:blood; D011897:Random Allocation; D013552:Swine / Q000097:blood / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000378:metabolism / Q000502:physiology; D013739:Testosterone / Q000097:blood
D009478:Neuropeptide Y; D004970:Estrone; D013739:Testosterone; D000735:Androstenedione; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D003577:Cytochrome P-450 Enzyme System; D015096:3-Hydroxysteroid Dehydrogenases; D004299:Dopamine beta-Hydroxylase; D009638:Norepinephrine