Novel Concepts in Neuroendocrine Regulation of Reproductive Tract Functions

1998 ◽  
pp. 125-144 ◽  
Author(s):  
Ch. V. Rao
2018 ◽  
Vol 38 (1) ◽  
pp. 25-35 ◽  
Author(s):  
S Carbone ◽  
OJ Ponzo ◽  
N Gobetto ◽  
YA Samaniego ◽  
R Reynoso ◽  
...  

The endocrine disruptor di-(2-ethylhexyl) phthalate (DEHP) is used in a variety of consumer products made with polyvinyl chloride and also in the manufacture of medical devices. DEHP disrupts reproductive tract development in an antiandrogenic manner and also may induce neurobehavioral changes. The aim of this study was to investigate the effects of chronic postnatal exposure to DEHP (30 mg/kg body weight/day, orally from birth to day 60) on the neuroendocrine regulation of the gonadal axis and its impact on the anxiety-like behavior in adult male rats, as well as the probable participation of the GABAergic system in these effects. DEHP produced a significant increase in plasmatic luteinizing hormone and follicle stimulating hormone, as well as significant testosterone decrease, accompanied with a decrease in hypothalamic gamma-aminobutyric acid (GABA) concentration. On the other hand, DEHP increased the anxiety-like behavior in the elevated plus maze test, evidenced by a significant decrease in the percentages of time spent in the open arms and the frequency in the open arm entries and a significant increase in the percentage of time spent in closed arms. Neuroendocrine and behavioral effects were reversed by GABA agonists, muscimol (2 mg/kg i.p. ) and baclofen (10 mg/kg i.p.). In conclusion, chronic DEHP postnatal exposure induced a disruption in the neuroendocrine regulation of the testicular axis in young adult male rats, and this effect was correlated with an anxiety-like behavior. Since GABA agonists reversed these effects, the results suggest that GABA could participate in the modulation of reproductive and behavioral DEHP effects.


1981 ◽  
Vol 240 (5) ◽  
pp. C165-C174 ◽  
Author(s):  
J. M. Marshall

This review concerns the influence of ovarian steroids and of pregnancy on norepinephrine (NE) metabolism in the adrenergic neurons of the female reproductive tract and speculates on the physiological consequences of this influence. Estrogen and progesterone affect not only the NE content of these nerves but also the turnover of NE, the activity of its synthetic enzyme, and releases of NE from nerve terminals. During pregnancy additional factors including stretch-induced hypertrophy come into play and cause degeneration of the nerves in the uterine corpus. This degeneration makes the muscle supersensitive to NE and may also induce morphological changes in the muscle cell membrane. As a result there may be a withdrawal of neural inhibitory influences on the corpus, allowing spontaneous myogenic contractions to intensify. Although the physiological significance of the steroid-transmitter interactions are still unclear, these nerves per se are of interest because they represent a model system for the study of neuroendocrine regulation in the peripheral nervous system.


Author(s):  
Mai M. Said ◽  
Ramesh K. Nayak ◽  
Randall E. McCoy

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.


Author(s):  
R.P. Apkarian ◽  
J.S. Sanfilippo

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.


Author(s):  
Lawrence M. Roth

The female reproductive tract may be the site of a wide variety of benign and malignant tumors, as well as non-neoplastic tumor-like conditions, most of which can be diagnosed by light microscopic examination including special stains and more recently immunoperoxidase techniques. Nevertheless there are situations where ultrastructural examination can contribute substantially to an accurate and specific diagnosis. It is my opinion that electron microscopy can be of greatest benefit and is most cost effective when applied in conjunction with other methodologies. Thus, I have developed an approach which has proved useful for me and may have benefit for others. In cases where it is deemed of potential value, glutaraldehyde-fixed material is obtained at the time of frozen section or otherwise at operation. Coordination with the gynecologic oncologist is required in the latter situation. This material is processed and blocked and is available if a future need arises.


Author(s):  
R. L. Reeder ◽  
S. H. Rogers ◽  
W. A. Shannon

Numerous morphological studies have dealt with the spermatheca of pulmonate gastropods. This globular organ, which is attached to the female portion of the reproductive tract by a long duct in these monoecious animals, has had various functions ascribed to it. Recent histochemical demonstrations of deoxyribonuclease, ribonuclease, protease, and acid phosphatase have provided, however, conclusive evidence that it is a digestive organ for the degradation of superfluous sperm and genital tract secretions. Only limited information concerning the spermatheca is available at the ultrastructural level, a fact providing the stimulus for the present study of this organ in Sonorella santaritana, a desert mountain snail from Arizona.


1967 ◽  
Vol 56 (1_Suppl) ◽  
pp. S106
Author(s):  
J. A. Edwardson

1970 ◽  
Vol 64 (3) ◽  
pp. 459-465 ◽  
Author(s):  
Ch. Owman ◽  
N.-O. Sjöberg ◽  
N. O. Sjöstrand ◽  
G. Swedin

ABSTRACT The effect of prolonged treatment with high doses of oestrogen and/or progesterone on the amount of adrenergic transmitter in the short adrenergic neurons of the male reproductive tract of castrated rats has been studied by chemical determinations and histochemical demonstration of noradrenaline. Oestrogen, progesterone, or a combination of both, had no overt effect on the total content or on the concentration of noradrenaline in the male genital organs. The results are discussed in the light of recent findings that the content of the noradrenaline transmitter in the short adrenergic neurons to the female genital tract is markedly influenced by these female sex hormones.


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