Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The histology and fine structure of the testis, epididymis and sex accessory glands were studied in young adult male rats administered testosterone enanthate, 120 microgram/100 g body weight, three times weekly for 4, 8, or 12 weeks. The weights of the testis and epididymis decreased, and animals treated for 11 weeks were infertile. Alterations were found in the seminiferous tubules of all rats treated for 8 or 12 weeks, including the presence of many degenerating germ cells and a large decrease or absence of late spermatids. Study of different stages of the cycle of the seminiferous epithelium showed that the greatest number of degenerating germ cells, step 7 spermatids and pachytene primary spermatocytes, occurred at stages VII-VIII of the cycle. Some normal appearing spermatogonia, primary spermatocytes and early spermatids remained in most seminiferous tubules. Sertoli cells contained many lipid droplets and lysosome-like bodies, and degenerating cells were surrounded by Sertoli cell cytoplasm. The Leydig cells of treated animals were greatly reduced in size. Sperm progressively disappeared from the lumen of the middle segment and proximal part of the terminal segment of the epididymis after treatment for 8 or 12 weeks. Changes in the middle segment also included the appearance of intraepithelial cavities containing debris, and the presence within the epithelium of phagocytic cells that resembled leukocytes. The lumen of the proximal part of the terminal segment was often collapsed, while in the distal part of the terminal segment, the lumen was filled with cellular debris and degenerating sperm. Organelles of the principal cells of the epididymal epithelium appeared to be qualitatively unaltered. The weight of the sex accessory glands remained close to normal, and the presence of normal ultrastructural features suggested that production of secretions continued.
Anat Rec 1978 Dec
PMID:Effects of testosterone enanthate on the structure of the male reproductive tract of the rat. 73 75

Biopsy and orchiectomy specimens were collected from two adult baboons (Papio anubis) at different intervals after intratesticular injection of H3-thymidine. Zenker-formol or Bouin's fixed materials were stained with PAS-Weigert-Hematoxylin and radioautographed using the H.S.R. (Harleco Synthetic Resin) coating technique. Morphological features of most germ cells appeared similar to those of other monkeys, except that the spermatids in steps 9 to 11 showed a spike-like projection of the acrosome. Also, the type A spermatogonia showed some resemblance to the human type A spermatogonia. The cell associations consisted of 12 stages and a large number of tubular cross sections showed the presence of two or more stages. In Papio anubis, the zygotene spermatocytes are formed in stage VIII, and spermatozoa are released during stages V and VI.
Anat Rec 1976 Jun
PMID:A study of germ cell morphology and duration of spermatogenic cycle in the baboon, Papio anubis. 81 23

In normal adult rats some germ cells degenerate at several vulnerable steps of spermatogenesis. These are the type A spermatogonia, midpachytene spermatocytes, primary and secondary spermatocytes which degenerate during their respective maturation divisions and step 7 and 19 spermatitids. In the present study, these degenerating cells were examined under the electron microscope, and their frequency was determined in toluidine blue stained semithin sections of testes from normal, hypophysectomized (at 5.5 days after operation) and hypophysectomized rats injected with FSH and LH separately or in combination. With the exception of the step 19 spermatids, the degenerating germ cells underwent necrosis in vacuolated spaces delimited by Sertoli cells. In the case of the affected step 19 spermatids, an apical cytoplasmic process of the Sertoli cell initially ensheathed a long segment of their flagellum, and then each degeneration cell was drawn deep in the seminiferous epithelium where it was phagocytozed by the Sertoli cell. Soon after hypophysectomy the incidence of degenerating mid-pachytene spermatocytes, step 7 and 19 spermatids which are present in stages VII or VIII of the cycle of the seminiferous epithelium, increased significantly. In contrast the number of degenerating primary or secondary spermatocytes during the meiotic divisions seen in stage XIV of the cycle or of any other germinal cell was not significantly modified. While the injection of FSH alone had no influence on the number of degenerating cells in hypophysectomized rats, injections of LH at the two doses administered (0.7 microng or 20 microng) reduced significantly the number of degenerating cells seen in stages VII-VIII of the cycle; combined injections of FSH and LH (20 microng) reduced the number of these degenerating cells to the normal low values. Thus it appeared that the mid-pachytene spermatocytes and the step 7 and 19 spermatids, all present in the adluminal compartment of the seminiferous epithelium in stages VII or VIII of the cycle, were more sensitive to the presence of absence of gonadotropic hormones than the other germ cells present in the seminiferous epithelium.
Anat Rec 1977 Mar
PMID:Degeneration of germ cells in normal, hypophysectomized and hormone treated hypophysectomized rats. 85 Dec 37

Rana pipiens larval beaks of consist of column cells, sheath cells and basal cells which supply cells to column and sheath. Each column consists of disk-like precone cells, cone cells and keratinized cone cells; they are cells in different stages of the process of keratinization. Breaks first appear externally at embryonic stage 24. Epidermal cells align at the tip of the jaw at stage 21. They increase in number and change in shape. Keratinization starts at stage 23. By stage 24, the apical column cells are keratinized and the histological organization is set for the whole larval period. During the larval period, the numbers of column cells increase until stages VIII or IV, stay relatively constant during mid-larval stages, and decrease at late larval stages. The beak is completely shed at stage XX. The widening of the beaks goes on during the entire larval period. Along the cutting edge of the jaw the tooth spikes increase in number and in individual width as the animal grows older and larger. Thyroid hormone causes a premature reduction of the column cell number and a precocious beak loss. The loss of break at metamorphic climax is thyroid dependent event.
Anat Rec 1975 Aug
PMID:Development of beaks of Rana pipiens larvae. 108 23

Basal and follicle-stimulating hormone (FSH)-stimulated cyclic AMP (cAMP) productions by seminiferous tubular segments from irradiated adult rats were investigated at defined stages of the epithelial cycle when specific spermatogenic cells were low in number. Seven days post-irradiation, depletion of spermatogonia did not influence the basal cAMP production, but FSH response increased in stages II-VIII. Seventeen days post-irradiation when spermatocytes were low in number, there was a small increase in basal cAMP level in stages VII-VIII and FSH-stimulated cAMP production increased in stages VII-XII and XIII-I. At 38 days when pachytene spermatocytes and round spermatids (steps 1-6) were low in number, a decreased basal cAMP production was measured in stages II-VI and IX-XII. FSH-stimulated cAMP output increased in stages VII-XII but decreased in stages II-VI. At 52 days when all spermatids were low in number, basal cAMP levels decreased in all stages of the cycle, whereas FSH response was elevated only in stages VII-XII. All spermatogenic cell types seem to have an effect on cAMP production by the seminiferous tubule in a stage-specific fashion. Germ cells appear to regulate Sertoli cell FSH response in a paracrine way, and a part of cAMP may originate from spermatids stimulated by an unknown FSH-dependent Sertoli cell factor. The FSH-dependent functions may control such phenomena as spermatogonial proliferation, final maturation of spermatids, and onset of meiosis.
Anat Rec 1990 May
PMID:Cellular regulation of basal and FSH-stimulated cyclic AMP production in irradiated rat testes. 216 27

Plasmids containing sequences 3' of the adult beta 1 globin gene of Xenopus laevis are unstable on propagation in a range of E. coli host strains. Up to 300 bp of Xenopus DNA are lost by rec A independent recombination between (AT)37 and (AT)17 sequences. Additionally, smaller deletions occurring in or around the (AT)37 sequence are observed. Deletion of these potential cruciform structures occurs in the absence of exonuclease I, exonuclease V and exonuclease VIII as the same pattern of deletion events is observed in recA recBC sbcB and recBC sbcA recE strains.
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PMID:RecBC, sbcB independent, (AT)n-mediated deletion of sequences flanking a Xenopus laevis beta globin gene on propagation in E. coli. 301 63

The RecE pathway of genetic recombination in Escherichia coli K-12 was defined to be the pathway that is utilized in deoxyribonucleic acid exonuclease V (ExoV)-defective cells which express constitutively recE+, the structural gene for deoxyribonucleic acid exonuclease VIII. Dependence on ExoVIII was shown by the occurrence in a recB21 sbcA23 strain of recombination deficiency mutations in recE, the structural gene for ExoVIII. Point mutations in recE were found as well as deletion mutations in which the entire Rac prophage, carrying recE, was lost. In addition, strain construction and mutagenesis revealed the dependence of the RecE pathway on recA+ and on recF+. Dependence on a fourth gene was shown by a mutation (rec-77) which does not map near the other genes. The problem of distinguishing the RecE pathway from that previously called RecF is discussed.
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PMID:Genetic analysis of the RecE pathway of genetic recombination in Escherichia coli K-12. 625 42

Mouse and guinea pig epididymal tissues have been investigated by light and electron microscopic autoradiography after long intervals ranging from 24 h to 5 days postinjection (p.i.) of the glycoprotein precursors, L-fucose-6-3H or D-glucosamine-1-3H. Using modified fixations to enhance glycoprotein preservation in situ, we found intense labelling of luminal contents in at least some of the epididymal segments after all the intervals investigated. At 24 h p.i., the label in guinea pig was associated with spermatozoa during remodelling of the acrosome in segment II, and at 3 days p.i., radioactivity was trapped within sperm head associations ("rouleaux") in segment IV of the epididymis. At this time, similar rouleau labelling extended from segment IV to segment VIII. In mouse, the luminal contents of the cauda epididymis were still intensely labelled at 5 days p.i.; analysis of the electron microscopic autoradiograms showed that relative grain concentration over the spermatozoa was twice that of the epididymal plasma. This concentration was especially elevated in the region of the sperm head. These findings taken together were interpreted as the binding of secreted epididymal glycoproteins to spermatozoa during sperm transit through the epididymis. In contrast to luminal contents, the labelling of the epididymal epithelium was generally lower, except on the clear cells which showed more pronounced labelling than the neighboring principal cells in mouse cauda epididymis at 5 days p.i. This label probably originated from the resorption of luminal glycoproteins.
Anat Rec 1984 Feb
PMID:Binding of secreted glycoproteins to spermatozoa in the mammalian epididymis: a fine-structure autoradiographic study. 670 37

The ontogeny of ascending and descending spinal pathways was examined in bullfrog (Rana catesbeiana) tadpoles using the transported histochemical marker, horseradish peroxidase (HRP). The adult pattern of brainstem projections to lumbar spinal cord is evident as early as larval stage I (Taylor and Kollros, Anat. Rec., 94:7-24, 1946), although the number and size of projecting cells increases as the animal matures. These projections arise from presumptive hypothalamic neurons at the diencephalic-mesencephalic border as well as from neurons of the vestibular nucleus, oculomotor nucleus, and reticular formation. In contrast to the stability of the pattern of descending projections, the sources of fibers ascending to the brainstem change during larval life. In early larval stages, brainstem projections from lumbar spinal cord arise primarily from Rohon-Beard cells and neurons of the superficial dorsal horn. In later stages, neurons in the intermediate and ventral areas of the spinal gray can also be retrogradely labeled by HRP application to the brainstem at the level of the VIIIth nerve. Evidence of the existence of dorsal column and lateral cervical nuclei in adult frog and tadpoles older than stage VIII is presented. The ascending projections of embryonically born primary neurons were also investigated. Rohon-Beard cells, which are sensory neurons with their cell bodies in the spinal cord, were found to send ascending processes as least as far rostral as the level of the VIIIth nerve entry zone. Anterolateral and dorsal marginal cells, probable homologs, respectively, of mammalian spinal border cells and cells of Waldeyer (1888), were also found to project rostrally at least to the rhombencephalon. These marginal cells persisted through metamorphosis into adulthood.
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PMID:Spinal cord development in anuran larvae: II. Ascending and descending pathways. 698 88

Throught stage VII and early stage VIII of the cycle of the seminiferous epithelium, the heads of the late spermatids, located in a juxtaluminal position, are embedded in apical processes of Sertoli cells. These processes contain cisternae of endoplasmic reticulum (ER) of two main types, i.e., flattened and tubular, which communicate with each other to form a continuous system. Throughout the long stage VII of the cycle, these two types of cisternae undergo marked changes. In early stage VII, the flattened cisternae, developing from the subsurface cisternae which compose the "junctional specialization," form concentric sheets at the periphery and in the middle of each apical process. The less conspicuous tubular cisternae form a continuous network which is present in the bridge connecting the Sertoli cell body to the apical process, and extends along the dorsal and ventral aspects of the spermatid's head to end up as cup-shaped flattened cisternae capping the bulbs of the tubulobulbar complexes described by Russell and Clermont ('76). In mid stage VII, the flattened cisternae start to regress, while the tubular cisternae become more abundant. In late stage VII, only fragments of the flattened cisternae are present, while the tubular cisternae form a profuse and elaborate network throughout the apical process. In the following stage VIII, the tubular cisternae disperse and only remnants of ER are present at the time of the release of the spermatid into the tubular lumen. These transformations of ER cisternae suggest a complex alteration in the relationship between Sertoli cells and late spermatids prior to their release as spermatozoa.
Anat Rec 1980 Jan
PMID:Evolution of the endoplasmic reticulum in the Sertoli cell cytoplasm encapsulating the heads of late spermatids in the rat. 741 4


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