The scrotal testes of albino rats aged 35 and 45 days were immersed in water at constant temperatures of 43 degrees C, 44 degrees C, or 45 degrees C for periods of 15-45 min in a special heating device. At an age of 60 days, the rats were mated in individual cages with two primiparous rats each. At an age of 90 days, they were killed and their testes were histologically processed. Rats with testes that had been subjected to heating when the animals were 45 days old showed both alterations of the seminiferous tubules and a decrease in fertilizing capacity. The effect of heat was greater in animals at 45 than at 35 days of age. In heat-treated testes, tubules contained PAS-positive concretion, sometimes engulfed by macrophage-derived giant cells and multinucleate cells derived from spermatids that failed to separate during spermiogenesis. The decrease in testicular volume observed after heat treatment was due mainly to reduced parenchymal volume. Thermic lability of seminiferous stem cells increases with age until adulthood, and recovery from heat injury declines.
An anatomical study of the tricuspid valve was carried out in 50 human hearts of both female and male individuals using a method of dissection which preserves the integrity of the valve. Morphometric criteria such as area of cusp, width of cusp base, relation between commissure depth and cusp depth and morphological criteria such as the presence of atrioventricular cusp node, number of tendinous cords, perimeter of fibrous ring, and properties of papillary m. were adopted for characterization of a cusp. In 64% of cases, commissural cusps were present independent of the number of tricuspid cusps. The tricuspid valve was not consistently tricuspid, but was observed to present 2, 4, 5 or 6 cusps in 72% of cases.
Doses of cimetidine (50 mg/kg b/w) were administered to adult male Wistar rats over 52 consecutive days. Besides plasma testosterone levels, morphological and morphometric aspects of the seminiferous tubules as well as histochemical analysis of the lipid content by oil red O were emphasized. Abnormal tubules exhibiting disorganization of their cellular association, loss of germ cells, and multinucleated giant spermatids were usually found. Significant reductions of testis weight and tubular diameter at specific stages (VII-IX), as well as lack of contact between Sertoli cells and spermatids in tubules at stage IX, suggest a possible interference of cimetidine on the histoarchitecture of the seminiferous epithelium. The dense concentration of lipid inclusions in tubules at postspermiation stages indicates phagocytosis and degradation of germ cells. Since no change in serum testosterone levels was verified in cimetidine-treated rats, the authors could not exclude the possibility that besides an antiandrogenic effect, other biochemical factors necessary for normal spermatogenesis could be involved in the testicular alterations.
Summary. Rats were surgically made bilaterally cryptorchid and after 4\p=n-\8days the testes were returned to the scrotum. After 70 days fertility was tested by pairing with females. Fertility was restored in 5/6 rats with testes cryptorchid for 4 or 5 days, but only 2/9 were fertile when the duration of cryptorchidism was 6\p=n-\8days. The sterility was due to irreversible degeneration of the spermatogonial stem cells. The testes of infertile males were smaller and lighter than those of fertile males and the seminiferous tubule diameters were reduced.
It has been confirmed that cryptorchidism may affect the control mechanism of gonadotrophin secretion. This has been based on morphological aspects of the adenohypophysis of cryptorchid rats which have shown an increase in basophilic and vacuolated basophilic cells, an increase known to be related to the production of gonadotrophin. The morphological alterations observed in the testes, prostates, seminal vesicles and ductus deferentes of these cryptorchid animals, the quiescence and the responses of their seminal vesicles and ductus deferentes to sympathomimetic and parasympathomimetic drugs indicated that these cryptorchid animals may be somewhere between normal and castrated rats, although not equidistant from either. Comparison of wet weights and of occurrence of spontaneous contractions, and determination of drug parameters in seminal vesicles and ductus deferentes taken from normal, castrated or crptorchid rats, suggested that the development and the spontaneous or the pharmacological responses of male accessory organs of reproduction are independent phenomena.
Early pubertal albino rats aged 20 days were made bilaterally cryptorchid by surgery, and groups with 5, 15, 25, and 35 days of cryptorchidism were submitted to bilateral orchiopexy. Fertility of all rats 110 days of age was tested by mating with female rats. Despite histological changes in the germinal epithelium of 35-day cryptorchid testes, orchiopexy restored fertility.
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