Ultrastructural effects of cigarette smoke on rat testis

The purpose of this study was to investigate the ultrastructural changes taking place in the testicular tissue of adult male Wistar rats following exposure to cigarette smoke. Twenty rats were exposed to smoke in a smoking machine for 2 h daily for 60 days; 10 control rats were placed in the machine for the same amount of time but were exposed to room air. After ether anesthesia and dissection of the animals, the testes were removed and fixed in 2.5% glutaraldehyde. The sections were examined under a transmission electron microscope. Evident degeneration and dissociation of the spermatogenetic cells were common findings. Basal lamina of the tubuli seminiferi contorti was thickened and significantly irregular. Cigarette smoke inhalation damaged the seminiferous epithelium. The primary spermatocytes as well as Sertoli cells appeared to be targets for the smoke. The results indicated that cigarette smoke inhalation could cause specific lesions in the development of spermatozoon, and it might be either directly or indirectly toxic to spermatogenesis.     

Interspecies study of statistical correlations existing between the pineal gland size and weight and brain and body weight in two groups of mammals. Interspecies study of correlations between the pineal gland and brain in the rat and in man

Network analysis procedures have been applied to study the cell patterns on the dorso medial and ventral lateral formation of the inferior colliculus of different species, i-e: Cat, Tat and Monkey. The results suggests the existence of important interspecific differences, more particularly in the primates. These differences are more obvious in the dorso medial formation. The functionnal implications of these results are discussed.     

Ultrastructural and physiological studies of the stalk-sectioned rat pituitary gland.

A pituitary stalk-section rat model was prepared that would be suitable for the study of the direct effects of steroids on the pituitary gland. In this model, the hypophyseal stalk was severed surgically and metal foil was inserted to prevent regeneration of portal vessels. The major portion of the pituitary no longer had a direct communication with the hypothalamus, and the only blood supply was from short portal vessels that supply the dorsolateral part of the gland. The effectiveness of the lesion was demonstrated by very high levels of serum prolactin and very low FSH and LH. Light microscopic examination revealed a large infarct in the central region of the gland with stainable cells in the peripheral area. Fourteen days after stalk-section, the infarct had shrunken appreciably, and after 21 days it was replaced by a scar. Ultrastructural studies revealed the presence of functional mammotropes in the peripheral regions of the pituitary gland, while other cells were smaller, less active, and contained fewer secretory granules. After LHRH administration there was an increase in serum LH, thus indicating the presence of a substantial number of viable gonadotropes. This was confirmed by the ultrastructural findings which now showed the appearance of large, well-granulated gonadotropes. When LHRH was given to estradiol 17-beta primed ovariectomized stalk-sectioned rats, there was a great augmentation of LH release, and many castration cells were now apparent. Therefore, the administration of estrogen and LHRH was needed for the gonadotropes of the isolated pituitary to function optimally in the synthesis and secretion of FSH and LH. The stalk-sectioned animal model permits evaluation of pituitary function isolated from hypothalamic control while it leaves the surviving pituitary gland in its normal anatomical position.     

Unravelling the role of pineal gland

The pineal gland has been classically considered as a vestigial organ with mystic properties. With the development of new methodical experiments, its physiologic actions are unravelled vary depending on the level of the phylogenetic scale. Since the discovery of melatonin as the principal hormone of the pineal gland, is an important hormone involved in the control of circadian rhythms and other diverse biological functions. Recent metabolic, receptor and functional studies have discovered melatoninergic system(s) in living organisms, its organization, physiology and a role in some pathologic conditions. The melatonin-generating system is characterized by three basic features: (1) photosensitivity, (2) diurnal (or circadian) rhythmicity (with highest levels of melatonin production occurring at night in darkness), and (3) age-related decline in its activity.     

Circadian rhythms in accessory sex gland function in the male rat

Alterations in various parameters of accessory sex gland function were monitored during two separate 24 h periods in adult male rats, and compared to fluctuations in the circulating levels of testosterone, prolactin, corticosterone and LH. Bimodal circadian rhythms in ventral prostate prolactin binding, cytosolic oestrogen binding and seminal vesicle weight could be discerned which appeared to be related to a similar rhythmicity in circulating testosterone levels, but with a phase shift of 3 h. Prostatic membrane bound adenylyl cyclase activities (basal and hormone stimulated) and prostatein concentrations followed different patterns possibly correlated to other endocrine changes.     

Symptomatic glial cysts of the pineal gland

Two cases of symptomatic glial cysts of the pineal gland are reported. An origin similar to that proposed for paraventricular glial cysts of the brain is accepted. These unusual lesions could be considered in the differential diagnosis of cystic pineal masses.     

Ultrastructural characteristics of the adrenal gland

The Adrenal glands can be viewed as sustaining vital processes in the human body, through two different but related components: the cortex and the medulla. It is well known that the close connection between the cortical cells is able not only to support the adrenal functions, but in the same time to serve the better understanding of the normal way of its hormonal production. Using the ultrastructural study of the adrenal gland, we obtain images which can provide informations about details of the cellular structure, in the eventuality that all this work will continue to improve to the point that we might be able to completely understand the complex interrelations between the structure of each cell and the function of the whole organ.     

Study on the pineal gland of ungulates]

Study of the pineal gland of 91 Ungulates belonging to 55 species shows the constant presence of calcarine concretions of various importance. These concretions develop in the walls of vessels that first undergo a preliminary transformation characterized by the presence of alcian blue or PAS positive substances. In nearly all cases, the presence of alcian blue positive cells with processes (distinct from mastocytes) can be found in the pineal gland of ungulates. These elements sometimes contain fine calcarine granulations that probably are the site of origin of acervuli. These observations were extended to several marsupials, carnivora, pinnipeda and perissodactyles.     

Atypical pleomorphic astrocytoma in the pineal gland: case report

OBJECTIVE AND IMPORTANCE: We report a rare case of pleomorphic astrocytoma in the pineal region that took a benign course despite pleomorphism. CLINICAL PRESENTATION: A 30-year-old woman suddenly developed right hemiparesis followed by loss of consciousness. A computed tomographic scan revealed a mass in the pineal region accompanied by obstructive hydrocephalus. Her symptoms improved after ventriculoperitoneal shunt surgery. INTERVENTION: The tumor was totally removed in an en bloc fashion using the occipital interhemispheric transtentorial route. Light microscopy revealed that the tumor had marked pleomorphism and multinucleated, bizarre giant cells, but neither mitosis nor necrosis was seen. Glial fibrillary acid protein was immunohistochemically positive in a few tumor cells. Retinal soluble antigen was negative. No reticulin network between the tumor cells was observed. A histological diagnosis of atypical pleomorphic astrocytoma was made. CONCLUSION: No signs of recurrence have been observed for 7 years after surgery without adjuvant therapy. Histologically, the tumor resembled pleomorphic xanthoastrocytoma or pleomorphic granular cell astrocytoma, but the immunohistochemical findings were not completely compatible with either diagnosis. This benign astrocytoma in the pineal gland with unique features is the first such case reported.     

Histological findings of the testis in male infertility

For successful treatment of male infertility, the pregnancy-expectant group must have a testis size larger than 12 ml and the FSH/LH index less than 0.99.     

Studies on relationship between testicular capsule and sperm transport in rat testis

Aim: In SD rats, histological changes in the testis were observed after bilateral capsulotomy (of the tunica albuginea) in order to investigate the physiological role of the testicular capsule on sperm transport. Methods: Bilateral longitudinal capsulotomy was devised to disrupt the capsular contractile function. With this technique, only the tunica vaginalis and tunlca albuginea were slit open, leaving the tunica vasculosa intact to embrace the underlying testicular parenchyma. After capsulotomy, the structural changes in the seminiferous tubules, the transitional distal seminiferous segment, and the rete testis were observed. Results: In the capsulotomized testis, there was sperm retention at the transitional seminiferous segment and progressive degenerative changes in seminiferous tubules. Conclusion: The results clearly indicated that an intact testicular capsule was required for normal sperm transport from the seminiferous tubules into the rete testis. This is the first attempt to study the physiological role of the testicular capsule in intact animals.     

Effect of the antiandrogen, WIN 49,596, on the descent of the testis in the male rat

Testicular descent in the male rat is believed to be an androgen dependent event with dihydrotestosterone the most likely active androgen. To provide further insight into the endocrinology of this important physiological event, we treated male rats with the antiandrogen, WIN 49596 (50 mg./kg./day), from day 1 to day 27 of age and evaluated its effect on the post-natal androgen-dependent events in this animal model. It was determined that while treatment with WIN inhibited the weights of the ventral prostate, seminal vesicles and penis when compared to those seen in castrate animals, the drug only caused a 19% (3/16) inhibition in the descent of the testes when compared to the control group (0/16; p = 0.112). These data together with those previously obtained in animals exposed to selective inhibitors of the 5-alpha reductase enzyme suggest that other factors possibly working in tandem with androgens play a predominant role in testicular descent in the rat.     

The role of pineal gland volume in the development of scoliosis

Purpose

Adolescent idiopathic scoliosis (AIS) is believed to be caused by genetic, neurological, osseous growth anomalies, histological variables including muscle fiber percentage and core structure changes, metabolic and hormonal dysfunction, vestibular dysfunction, and platelet microarchitecture. The objective of this study was to contribute to the determination of the cause of AIS by analyzing the changes in pineal gland volume in AIS cases.

Methods

Study (AIS) and control group were each comprised of 26 patients who met the inclusion requirements. Scoliosis radiograph and MRI of the pineal glands were used for radiological examinations. The distribution of age, gender, Risser grading for skeletal radiological development, and sexual maturation according to Tanner categorization were uniform and statistically insignificant between groups.

Results

When the pineal gland volumes of the cases were evaluated according to age, the AIS group was found to have significantly reduced pineal gland volumes in all age groups. The pineal gland volume was found to be 38.1% lower in the AIS group compared to the control group (p˂0.001). In the AIS group, patients aged 13 years had the lowest pineal gland volume (77.2 ± 13.86 mm³), while patients aged 15 years had the highest volume (97.9 ± 16.47 mm³).

Conclusion

Changes in pineal gland volume support the role of the pineal gland in the etiopathogenesis of AIS.

     

Embryonal carcinoma with teratomatous elements in the region of the pineal gland

An embryonal carcinoma with teratomatous elements arising in the region of the pineal gland of an eight-year-old boy is reported. Radiation therapy, chemotherapy and surgical intervention failed, and he died 16 months after the onset of the symptoms. His clinical and autopsy findings are described.     

Thyroid-testis interrelationship during the development and sexual maturity of the rat

The effects of thyroidectomy and treatment with thyroxine (T4) were studied in immature male rats to evaluate the role of the thyroid in the development of testicular functions. Thyroidectomy inhibited gametogenesis and development of the Leydig cell in these rats. However, the effects could be reversed by administration of 10 micrograms T4 (i.p.) daily for 30 days.