The Effect of Pineal Grafts, Pinealectomy, and Denervation of the Pineal Gland on the Reproductive Organs of Male Hamsters

1967 ◽  
Vol 2 (3) ◽  
pp. 138-146 ◽  
Author(s):  
Russel J. Reiter
Keyword(s):  
Pineal Gland ◽  
Reproductive Organs

PHYSIOLOGICAL EFFECTS OF THE PINEAL GLAND IN ANDROGEN-STERILIZED FEMALE RATS

1970 ◽  
Vol 63 (4) ◽  
pp. 667-678 ◽  
Author(s):  
Russel J. Reiter
Keyword(s):  
Pineal Gland ◽  
Reproductive Organs ◽  
Female Rats ◽  
Inhibitory Influence ◽  
Light Deprivation ◽  
Vaginal Smears ◽  
Adult Rats ◽  
Androgen Treatment ◽  
Postnatal Treatment ◽  
Cervical Ganglia

ABSTRACT The influence of early androgen treatment, light deprivation (by blinding), pinealectomy and superior cervical ganglionectomy on the reproductive system of female rats was tested. Early postnatal treatment of rats with testosterone propionate caused adult rats to exhibit the characteristic signs of androgen sterilization; these included polyfollicular ovaries, normal-sized uteri and persistent vaginal cornification. If early androgentreated rats also were blinded the ovaries were smaller in size and contained fewer follicles, the uteri were greatly reduced in size and the incidence of vaginal oestrus was decreased by approximately 50% If in addition to blinding, androgen-sterilized animals were subjected to either removal of the pineal gland or superior cervical ganglia, the reproductive organs and the vaginal smears were indistinguishable from those of testosterone-treated rats with eyes. These data indicate that the inhibitory influence of blinding on the pituitary-ovarian axis was mediated through the sympathetic nervous system and the pineal gland. The restraining influence of light deprivation on the growth of the reproductive organs was not permanent as illustrated by the fact that if these animals were kept to 120 days of age the ovaries and uteri grew to the same level as those of pinealectomized control rats.

RELATIONSHIP BETWEEN THE PINEAL GLAND, OTHER ENDOCRINE GLANDS AND REPRODUCTIVE ORGANS OF SINGLE AND PARABIOSED GOLDEN HAMSTERS

1973 ◽  
Vol 74 (3) ◽  
pp. 434-448 ◽  
Author(s):  
Hugo R. Seibel ◽  
Michael R. Schweisthal
Keyword(s):  
Pineal Gland ◽  
Reproductive Organs ◽  
The Other ◽  
Endocrine Function ◽  
Target Organs ◽  
Gonadal Atrophy ◽  
Testicular Weight ◽  
Seminal Vesicle Weight ◽  
Group 5 ◽  
Group 2

ABSTRACT Investigations on the role of the pineal body have recently assigned an endocrine function to this gland. Ablation of the gland results in an increase in testicular weight. Bilateral enucleation of the eyes results in pineal hypertrophy and gonadal atrophy. The following experimental groups were studied in the adult male and female: (1) controls; (2) pinealectomized; (3) bilaterally enucleated; (4) bilaterally enucleated pinealectomized; (5) bilaterally enucleated sham pinealectomized. The following groups were studied in parabiosed animals: (1) both animals normal; (2) both animals bilaterally enucleated; (3) both animals bilaterally enucleated and pinealectomized; (4) one animal bilaterally enucleated and the other normal; (5) one animal bilaterally enucleated and pinealectomized and the other normal. Animals were killed from 4 to 6 weeks after the start of the experiment. Weights of the testes, seminal vesicles, adrenals, pituitary, uteri and ovaries served as parameters. Histological studies on these tissues were carried out. With regard to the target organs, sham operated did not differ from normal animals. Bilateral enucleation resulted in gonadal and accessory sex organ atrophy. These effects were prevented by pinealectomy. Pinealectomy of blinded single males with atrophic gonads was followed by a regeneration of the testicular epithelium within 6 to 8 weeks. After parabiotic union in groups (2) and (5), a decrease in testicular and seminal vesicle weight was observed; uterine and ovarian weights were decreased in group (2), while in group (5) only ovarian weight was decreased. These results suggest that bilateral enucleation (darkness) activates the pineal gland to secrete a substance(s) which modifies the hypophyseal target organ axis in both single and parabiotic animals.

scholarly journals Response of the Chicken Pineal Gland, Blood and Reproductive Organs to Darkness

1969 ◽  
Vol 48 (3) ◽  
pp. 903-907 ◽  
Author(s):  
L.Z. McFarland ◽  
W.O. Wilson ◽  
C.M. Winget
Keyword(s):  
Pineal Gland ◽  
Reproductive Organs

scholarly journals Historical Perspective and Evaluation of the Mechanisms by which Melatonin Mediates Seasonal Reproduction in Mammals

2018 ◽  
Vol 1 (1) ◽  
pp. 59-77 ◽  
Author(s):  
Russel J Reiter ◽  
Dun-Xian Tan ◽  
Ramaswamy Sharma
Keyword(s):  
Pineal Gland ◽  
Reproductive Organs ◽  
Day Length ◽  
Optimal Time ◽  
Seasonal Reproduction ◽  
Pars Tuberalis ◽  
Short Day ◽  
Long Day ◽  
Time Of Year ◽  
Photoperiod Sensitive

The discovery of melatonin and its photoperiod-regulated circadian rhythm were important milestones in defining the events associated with the regulation of seasonal reproduction in both short-day and long-day breeding mammals. By means of the seasonal changes in the duration of the nocturnal melatonin rise, which provides both clock and calendar information, animals adjust their reproductive state to the appropriate time of year. Thus, melatonin dictates the proper season for mating which ensures the optimal time for delivery of offspring. The photoperiodic information is transduced into a chemical messenger, melatonin, in the pineal gland. The initial studies related to the importance of day length and the melatonin message in impelling seasonal reproduction involved the use of photoperiod-sensitive rodents, especially several long-day breeding hamster species. Since then, a large group of interested reproductive biologists have extended these findings to numerous other mammals including short-day breeding ungulates. Moreover, critical information related to the molecular processes at the level of the pars tuberalis of the anterior pituitary and the mediobasal hypothalamus has been provided. In this scheme, the pars tuberalis, until recently an almost ignored portion of the adenohypophysis, has been identified as a critical intermediate between the melatonin signal and the functional state of the reproductive organs. It is somewhat ironic that two organs, the pineal gland and the pars tuberalis, which suffered with the image of vestigiality for so long have now been identified as unequivocally essential for this most basic and important function, i.e., regulating seasonal reproduction.

Ultrastructural aspects of gymnosperms reproductive organs tissues due to their functional condition

1978 ◽  
Vol 36 (2) ◽  
pp. 440-441
Author(s):  
G. M. Kozubov
Keyword(s):  
Metabolic Activity ◽  
Functional Condition ◽  
Reproductive Organs ◽  
Considerable Change ◽  
Complicated Structure ◽  
Tetrad Stage ◽  
Ubisch Bodies ◽  
Similar Organization ◽  
Female Reproductive Organs ◽  
High Metabolic Activity

The ultrastructure of reproductive organs of pine, spruce, larch and ginkgo was investigated. It was found that the male reproductive organs possess similar organization. The most considerable change in the ultrastructure of the microsporocytes occur in meiosis. Sporoderm is being laid at the late tetrad stage. The cells of the male gameto-phyte are distinguished according to the metabolic activity of the or- ganells. They are most weakly developed in the spermiogenic cell. Ta-petum of the gymnosperms is of the periplasmodic - secretorial type. The Ubisch bodies which possess similar structure in the types investigated but are specific in details in different species are produced in tapetum.Parietal and subepidermal layers are distinguished for their high metabolic activity and are capable of the autonomous photosynthesis. Female reproductive organs differ more greatly in their struture and have the most complicated structure in primitive groups. On the first stages of their formation the inner cells of nucellus are transformed into the nucellar tapetum in which the structures similar to the Ubisch bodies taking part in the formation of the sporoderm of female gametophyte have been found.

Pelvic Impairments

2018 ◽  
Vol 23 (4) ◽  
pp. 9-10
Author(s):  
James Talmage ◽  
Jay Blaisdell
Keyword(s):  
Pelvic Ring ◽  
Reproductive Organs ◽  
High Impact ◽  
Pelvic Fractures ◽  
Motor Dysfunction ◽  
Impact Event ◽  
Concomitant Injuries ◽  
Rating Process ◽  
Pass Through ◽  
A Minor

Abstract Pelvic fractures are relatively uncommon, and in workers’ compensation most pelvic fractures are the result of an acute, high-impact event such as a fall from a roof or an automobile collision. A person with osteoporosis may sustain a pelvic fracture from a lower-impact injury such as a minor fall. Further, major parts of the bladder, bowel, reproductive organs, nerves, and blood vessels pass through the pelvic ring, and traumatic pelvic fractures that result from a high-impact event often coincide with damaged organs, significant bleeding, and sensory and motor dysfunction. Following are the steps in the rating process: 1) assign the diagnosis and impairment class for the pelvis; 2) assign the functional history, physical examination, and clinical studies grade modifiers; and 3) apply the net adjustment formula. Because pelvic fractures are so uncommon, raters may be less familiar with the rating process for these types of injuries. The diagnosis-based methodology for rating pelvic fractures is consistent with the process used to rate other musculoskeletal impairments. Evaluators must base the rating on reliable data when the patient is at maximum medical impairment and must assess possible impairment from concomitant injuries.

Monosodium glutamate administration early in life alters pineal melatonin nocturnal profile in adulthood

2021 ◽  
Vol 4 (1) ◽  
pp. 99-114
Author(s):  
Janaína B Garcia ◽  
Fernanda G Do Amaral ◽  
Daniela C Buonfiglio ◽  
Rafaela FA Vendrame ◽  
Patrícia L Alves ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Body Weight ◽  
Pineal Gland ◽  
Serum Insulin ◽  
Monosodium Glutamate ◽  
Female Rats ◽  
Pineal Melatonin ◽  
Melatonin Synthesis ◽  
Male And Female Rats ◽  
Melatonin Production

The pineal gland synthesizes melatonin exclusively at night, which gives melatonin the characteristic of a temporal synchronizer of the physiological systems. Melatonin is a regulator of insulin activities centrally and also peripherally and its synthesis is reduced in diabetes.  Since monosodium glutamate (MSG) is often used to induce the type 2 diabetic and metabolic syndrome in animal models, the purpose of this work is to evaluate the potential effects of MSG given to neonates on the pineal melatonin synthesis in different aged male and female rats. Wistar rats were subcutaneously injected with MSG (4mg/g/day) or saline solution (0.9%) from the second to eighth post-natal day. The circadian profiles both melatonin levels and AANAT activity were monitored at different ages. Body weight, naso-anal length, adipose tissues weight, GTT, ITT and serum insulin levels were also evaluated. Typical obesity with the neonatal MSG treatment was observed, indicated by a great increase in adipose depots without a concurrent increase in body weight. MSG treatment did not cause hyperglycemia or glucose intolerance, but induced insulin resistance. An increase of melatonin synthesis at ZT 15 with phase advance was observed in in some animals. The AANAT activity was positively parallel to the melatonin circadian profile. It seems that MSG causes hypothalamic obesity which may increase AANAT activity and melatonin production in pineal gland. These effects were not temporally correlated with insulin resistance and hyperinsulinemia indicating the hypothalamic lesions, particularly in arcuate nucleus induced by MSG in early age, as the principal cause of the increase in melatonin production.

Sign in / Sign up

Export Citation Format

Share Document