DOCSLIB.ORG

Seminiferous Tubules in Hypophysectomizedrams Treated with Pituitary

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Seminiferous Tubules in Hypophysectomizedrams Treated with Pituitary Effects of a single brief period of moderate heating of the testes on seminiferous tubules in hypophysectomized rams treated with pituitary extract M. T. Hochereau-de Reviers, A. Locatelli, C. Perreau, C. Pisselet and B. P. Setchell Reproductive Physiology Station, INRA. URA CNRS 1291, Nouzilly 37380, Monnaie, France; and 2On study leave from Department of Animal Sciences, Waite Agricultural Research Institute, The University of Adelaide, Glen Osmond 5064, South Australia, Australia An experiment was conducted to examine the appearance of the seminiferous tubule 20 days after a single exposure of the testes of rams to a scrotal temperature of about 42\s=deg\Cfor 45 min. Ten of the animals were surgically hypophysectomized and five were simultaneously heated; these rams were treated twice a day with ovine pituitary extract to avoid modifi- cations in the negative feedback from the testes to the pituitary and consequent changes in gonadotrophin secretion. Six intact rams (three heated and three unheated) were also studied. The pituitary extract significantly increased the testis weight and spermatogonial multipli- cations from A1 spermatogonia onwards. Twenty days after the heat treatment, testis weight was significantly reduced by heating; both tubular and intertubular tissues were affected. The total length of seminiferous tubules per testis was not modified, whereas the mean seminiferous tubule diameter was significantly reduced after heating. The total number of Sertoli cells per testis was not significantly modified, while their mean cross-sectional nuclear area was significantly reduced by heat treatment. A decrease in the number of all germ cells except A0 spermatogonia, from A1 spermatogonia onwards, was observed. The number of round spermatids decreased by 95 and 90%, slightly more than the diplotene primary spermatocytes (76 and 77%) and elongated spermatids (79 and 85%) in hypophysectomized pituitary extract-treated and intact rams, respectively. Round and elongated spermatids would be derived from germ cells that were respectively leptotene and young pachytene primary spermatocytes at the time of heating, whereas diplotene primary spermatocytes would have been type B spermatogonia. Normal spermiation did not take place and some testicular spermatozoa remained loosely attached to the seminiferous epithelium. It is con- cluded that this mild heat treatment caused considerable disruption to the spermatogenic cells, but the effect was comparable in intact rams, in which pituitary gonadotrophin secretion may have changed and in hypophysectomized rams treated with a constant dose of pituitary extract. Introduction of heating on local paracrine control from effects due to changes in gonadotrophin secretion. Interstitial tissue volumes, semin¬ iferous tubule Sertoli and cell Degeneration of the seminiferous epithelium induced by a short parameters, germ populations period of local hyperthermia has been extensively studied since were analysed. the results obtained in rats by Steinberger and Dixon (1959), and Chowdhury and Steinberger (1964) and Collins Lacy (1969) Materials and Methods and in rams by Waites and Ortavant (1968). However, after that induce of modifi¬ treatments disruption spermatogenesis, Animals cations of the intratesticular local paracrine control cannot be in secretion which dissociated from changes gonadotrophin Sixteen Ile de France adult rams were used during the season could modify germ cell production. of sexual activity, between September and December 1987. The work was the effect of a The aim of the present to analyse complete description of animals and methods of heating are mild scrotal in normal rams and in rams brief episode of heating given in a previous paper (Setchell et al, 1991). The pituitaries constant stimulation of the to dissociate the effects with testis, of ten rams (Hy) were removed surgically by\|he parapharyn- Received 23 March 1992. geal route, under halothane anaesthesia (Fluothan: Pitman Downloaded from Bioscientifica.com at 09/29/2021 12:48:31PM via free access Moore 3% in 02; 103mlmin_1). Each ram received a sup¬ ation, and on 10 cross-sections at stage 2 of the classification, plementation twice a day with ovine pituitary acetone extract during the elongation of the spermatid nuclei. These numbers in saline suspension at a dose of 120 mg for 19 days were not corrected for their size and consequently the total by intramuscular injection. One milligram of this powder is numbers of elongated spermatids per testis or of spermatozoa equivalent to 40 µg of NIH Si FSH, in a bioassay of FSH after spermiation were greater than those calculated for round according to Steelmann and Powley (1953). Five of the rams spermatids. At both of these stages (6—7 and 2, respectively), were submitted at the same time to hypophysectomy (HyH) the percentages of tubules with elongated spermatids or and local testicular hyperthermia, produced by immersing the testicular spermatozoa were calculated. shaved scrotum in a temperature-controlled water bath so that the rose 42 subcutaneous temperature to between and 43°C, Statistical analyses over 15 min and remained there for 45 min (four rams) or 30 min (one ram). There was no difference due to the time of All results were evaluated by two-way analysis of variance exposure in the effect on testis weight, and the results have with hypophysectomy-hormone treatment and heating as therefore been pooled. The other five hypophysectomized factors or by nonparametric U test (Mann and Whitney, 1947). rams were treated with pituitary extract but not heated (HyU). Three intact normal rams were submitted to scrotal hyper¬ thermia (IH; two for 45 min; one for 30 min, see above) and Results three were not heated (IU). All the Hy rams were given corti¬ sone (4 ml on day 1, 3 ml on day 2, 2 ml on day 3 and 1 ml on Testis weight, interstitial tissue volume and seminiferous tubule day 4 of a 25 mg ml-1 solution) and penicillin (Extancilline, parameters Specia 2.4 x IO6 units on day 1 and 1.2 106 units on days 2 and 3). On day 20 after heating or hypophysectomy, the Testis weight was significantly reduced by heat treatment, in animals were castrated under anaesthesia. both hypophysectomized HyH and intact IH rams, by 55 and 46%, respectively (Table 1). In addition, the testis was signifi¬ Histological and morphometric techniques cantly heavier in pituitary extract treated—hypophysectomized HyU than in normal intact IU rams ( + 33%). The relative All the analyses were performed on the right testis of each volume of seminiferous tubules in the testicular parenchyma ram, as no difference between the left and testes was significantly decreased by heating ( 8.4 and —9.4% significant right — was previously detected. Pieces of testicular parenchyma (1 or respectively; = 0.05) in HyH and IH rams. However, both 2 cm3) were fixed in Bouin Hollande solution for histological interstitial tissue and seminiferous tubules were affected by analysis. Analysis of intertubular and tubular tissues was per¬ heating. The total volume of interstitial tissue was reduced 44 and and formed as previously described (Hochereau-de Reviers et al, following heating by 32%, respectively, in HyH IH 1992). The relative volumes of intertubular tissue and of semini¬ rams. Total length of seminiferous tubule per testis was not ferous tubules were determined with a 25-point ocular integra¬ modified significantly by any treatment. The mean diameters of tor on 20 fields from each testis. The diameters of the seminifer¬ seminiferous tubules were significantly decreased by heat treat¬ ous tubules cut in cross-section were determined with a ment in IH ( 23%) or HyH ( 32%) rams and significantly graphic — — tablet analysis program (Apple Software) on 20 cross-sections increased in HyU ( +15%) compared with normal IU rams. As a per animal. The total length of the seminiferous tubules per result of variations in length and diameter of the seminiferous testis was calculated from the testis weight, the relative volume tubules, the surface areas of their basement membrane per of seminiferous tubules and the cross-sectional area of semini¬ Sertoli cell were significantly depleted by heating. The total ferous tubules (Attal and Courot, 1963) after correction for numbers of Sertoli cells per testis were not affected by any histological shrinkage. treatment, whereas their nuclear cross-sectional areas were The Sertoli cells, and significantly decreased by heat treatment ( 15% in HyH and A0, Ax spermatogonia, leptotene diplo¬ — tene and round were counted 9% in IH rams, respectively; < 0.05; Table 1). primary spermatocytes spermatids — in 10 cross-sections (10 µ thick) at stage 8 (spermatogonia and 1 and round spermatids), stage (leptotene), stage 3 (diplotene) of Germ cell the cycle of the seminiferous epithelium (Ortavant, 1959). For populations these cells, the corrected numbers of nuclei per cross-section, The total numbers of A0 spermatogonia per testis were not including those of the Sertoli cells that were assumed to be affected by any treatment (Table 2). Heating the testes induced spheres, were calculated by the formula of Abercrombie (1946). a significant fall, 20 days later, in the daily production of Aj The nuclear cross-sectional area of Sertoli cells was measured on spermatogonia, by 54 and 45% in HyH and IH rams, respect¬ 20 nuclei per animal at stage 8 (Ortavant, 1959). The total ively. Heating the testes induced a significant fall in the daily numbers of Sertoli and germ cells per testis were calculated production of leptotene primary spermatocytes, 20 days later, from the total length of seminiferous tubules per testis and the to the same extent as that of Aj spermatogonia ( 64 and — corrected numbers of germ cells per cross-section. The daily 30% in HyH and IH rams, respectively); gonadotrophin treat¬ — production of germ cells was calculated from their total ment of hypophysectomized rams significantly increased this numbers per testis divided by the duration of the seminiferous daily production in HyU rams compared with normal IU rams epithelium cycle, i.e. 10.4 days in the ram (Ortavant, 1959).
Load more

Recommended publications
  • Male Reproductive System
    MALE REPRODUCTIVE SYSTEM DR RAJARSHI ASH M.B.B.S.(CAL); D.O.(EYE) ; M.D.-PGT(2ND YEAR) DEPARTMENT OF PHYSIOLOGY CALCUTTA NATIONAL MEDICAL COLLEGE PARTS OF MALE REPRODUCTIVE SYSTEM A. Gonads – Two ovoid testes present in scrotal sac, out side the abdominal cavity B. Accessory sex organs - epididymis, vas deferens, seminal vesicles, ejaculatory ducts, prostate gland and bulbo-urethral glands C. External genitalia – penis and scrotum ANATOMY OF MALE INTERNAL GENITALIA AND ACCESSORY SEX ORGANS SEMINIFEROUS TUBULE Two principal cell types in seminiferous tubule Sertoli cell Germ cell INTERACTION BETWEEN SERTOLI CELLS AND SPERM BLOOD- TESTIS BARRIER • Blood – testis barrier protects germ cells in seminiferous tubules from harmful elements in blood. • The blood- testis barrier prevents entry of antigenic substances from the developing germ cells into circulation. • High local concentration of androgen, inositol, glutamic acid, aspartic acid can be maintained in the lumen of seminiferous tubule without difficulty. • Blood- testis barrier maintains higher osmolality of luminal content of seminiferous tubules. FUNCTIONS OF SERTOLI CELLS 1.Germ cell development 2.Phagocytosis 3.Nourishment and growth of spermatids 4.Formation of tubular fluid 5.Support spermiation 6.FSH and testosterone sensitivity 7.Endocrine functions of sertoli cells i)Inhibin ii)Activin iii)Follistatin iv)MIS v)Estrogen 8.Sertoli cell secretes ‘Androgen binding protein’(ABP) and H-Y antigen. 9.Sertoli cell contributes formation of blood testis barrier. LEYDIG CELL • Leydig cells are present near the capillaries in the interstitial space between seminiferous tubules. • They are rich in mitochondria & endoplasmic reticulum. • Leydig cells secrete testosterone,DHEA & Androstenedione. • The activity of leydig cell is different in different phases of life.
    [Show full text]
  • Determination of the Elongate Spermatid\P=N-\Sertolicell Ratio in Various Mammals
    Determination of the elongate spermatid\p=n-\Sertolicell ratio in various mammals L. D. Russell and R. N. Peterson Department of Physiology, School of Medicine, Southern Illinois University, Carbondale, IL 62901, U.S.A. Summary. Criteria were devised for determining the elongate spermatid\p=n-\Sertolicell ratio in various mammalian species at the electron microscope level. When data from particular species were pooled, the values were: rabbit, 12\m=.\17:1,hamster, 10\m=.\75:1; gerbil, 10\m=.\64:1;rat, 10\m=.\32:1; guinea-pig, 10\m=.\10:1;vole, 9\m=.\75:1;and monkey, 5\m=.\94:1. The elongate spermatid\p=n-\Sertolicell ratio is a measure of the workload of the Sertoli cell and is a prime factor determining their efficiency. The higher the ratio, the higher the sperm output is likely to be per given weight of seminiferous tubule parenchyma for a particular species. Introduction The number of spermatozoa provided in the ejaculate is determined by a number of factors but the major influence is the number of spermatozoa produced in the testis. In mammals that breed continuously testicular sperm production appears to be related to the size of the testis, especially the seminiferous tubule compartment. Here the kinetics of spermatogenesis dictate how many germ cells (spermatogonia) become committed to the spermatogenic process and also the time it takes these germ cells to go through various cell divisions and transformations to become a spermatozoon. The index of sperm production, or the daily sperm production, is expressed as the number of spermatozoa produced per day by the two testes of an individual, whereas the index of efficiency of sperm production is the number of spermatozoa produced per unit weight or volume of testicular tissue (Amann, 1970).
    [Show full text]
  • Seminiferous Tubules to Epididymis in the Mouse: a Histological and Quantitative Study
    TRANSPORT OF SPERMATOZOA FROM SEMINIFEROUS TUBULES TO EPIDIDYMIS IN THE MOUSE: A HISTOLOGICAL AND QUANTITATIVE STUDY BRUCE M. BARACK Department of Anatomy, Washington University School of Medicine, St. Louis, Missouri, U.S.A. (Received 1st May 1967) Summary. The histology and structure of the seminiferous tubules, the tubuli recti, the rete testis and the ductuli efferentes of the adult albino mouse were studied in conjunction with the effect of unilateral ligation of the ductuli efferentes on the testis of the operated side under various experimental conditions. Results indicate that the amount of fluid produced within the testis is sufficient to flush the tubular system at least once a day and therefore eight times/spermatogenic cycle and that this fluid passage is the major factor in the transport of spermatozoa from the seminiferous tubules to the ductuli efferentes. The possibility of an interaction between the Sertoli cell and associated spermatids in early spermiogenesis resulting in secretion of fluid by the Sertoli cell is discussed. INTRODUCTION The mechanism of transport of immotile spermatozoa from the seminiferous tubules to the epididymis is still in question. The consequences of unilateral ligation of the ductuli efferentes or the head of the epididymis on the testis of the operated side have been described by Van Wagenen (1924, 1925), White (1933), Harrison (1953) and Harrison & Macmillan (1954) in the rat; Ladman & Young (1958) in the guinea-pig; Baillie (1962) in the mouse and Gaddum & Glover (1965) in the rabbit. These investigators found that following ligation there occurs a generalized dilatation of the seminiferous tubules accompanied by a varying degree of shedding and/or degeneration of the seminiferous epithelium.
    [Show full text]
  • PROTEINS of the SEMINIFEROUS TUBULE FLUID in MAN\P=M-\EVIDENCEFOR a BLOOD\P=M-\TESTISBARRIER
    PROTEINS OF THE SEMINIFEROUS TUBULE FLUID IN MAN\p=m-\EVIDENCEFOR A BLOOD\p=m-\TESTISBARRIER AARNE I. KOSKIMIES, MARTTI KORMANO and OLOF ALFTHAN Department of Anatomy, University of Helsinki, and Department of Urology of the Second Surgical Clinic, University Central Hospital, Helsinki, Finland (Received 16th December 1971) Summary. Seminiferous tubule fluid was collected by micropuncture from ten human testes immediately after orchidectomy and subjected to high resolution step gradient acrylamide gel electrophoresis. The pro- tein patterns of the fluid were compared with those of serum and intratesticular lymph. The seminiferous tubule fluid always contained a number of proteins not seen in serum or in testicular lymph and a few proteins which were electrophoretically identical with those in serum. The bulk of these relatively weak serum bands consisted of albumin. Disturbance of spermatogenesis did not influence either the appearance of specific proteins or the degree of serum contamination. The present results are interpreted to mean that in man, as in ani- mals, there is an effective blood\p=m-\testisbarrier. The specific proteins of the seminiferous tubules may be elaborated by Sertoli cells. INTRODUCTION The seminiferous tubules secrete a fluid which carries the spermatozoa out of the testis and into the epididymis. The existence of such a fluid has been recognized for some time (von Mihalkovics, 1873; Stieda, 1877), and its circulation was studied microscopically either in normal testes (Rolshoven, 1936) or after ligation of the efferent ducts in experimental animals (Young, 1933). However, it has only recently been shown that the composition of the fluid is unique. This is due both to the existence of a barrier mechanism which prevents the entry of various substances into the seminiferous tubule and to secretory phenomena within the seminiferous epithelium (Setchell, 1971).
    [Show full text]
  • Pdf (726.57 K)
    The Egyptian Journal of Hospital Medicine (July 2017) Vol.68 (2), Page 1260-1271 The Diagnostic Value of Combined Conventional MRI and Diffusion Weighted MRI in Diagnosis of Non-Palpable Undescended Testes Aisha Dabnon Abd Alnabie Faculty of Medicine, Ain Shams University ABSTRACT Background: MRI is noninvasive imaging tool, does not involve ionizing radiation and yields multiplanar images but it is sometimes less efficient in locating intra-abdominal functioning testicles and it fails to locate most of the atrophied testicles. Additional MRI assessments, as fat-suppressed T2WI and DWI are useful methods to improve the accuracy and sensitivity of diagnosis of non-palpable testes. Objective of the Study: is to assess the value of adding diffusion-weighted sequences (DWI) to routine magnetic resonance imaging (MRI) in identifying and locating nonpalpable undescended testes. Results: a combination of DWI and conventional MRI including Fat-supp. T2WI sequence is the most accurate means of detecting and localizing non-palpable undescended testes. The findings of DWI complement the information on the location of undescended testes obtained with conventional MRI. In addition, DWI is helpful in detection of testicular viability or atrophy properly before the operation. Keywords: magnetic resonance imaging; undescended testes, diffusion, fat-suppression T2WI. been shown to have low sensitivity in identifying INTRODUCTION non- Undescended testis or cryptorchidism, a condition in which one or both testicles are not appropriately positioned in the scrotum at birth. It is the most palpable testicles preoperatively in a recent meta- common congenital genitourinary anomaly in boys analysis (4). and has an incidence of 1–3% in term and 15–30% in Conventional MRI is moderately specific in premature male infants.
    [Show full text]
  • Histology of Male Reproductive System
    Histology of Male Reproductive System Dr. Rajesh Ranjan Assistant Professor Deptt. of Veterinary Anatomy C.V.Sc, Rewa 1 Male Reproductive System A-Testis B-Epididymis C-Ductus Deferens D-Urethra 1-Pelvic part 2-Penile part E-Penis G-Accessory Glands 1. Seminal vesicles 2-Prostate gland 3-Bulbouretheral gland/ Cowper’s gland Testis The testis remains covered by: Tunica vaginalis- The outermost covering (peritoneal covering of the testis and epididymis). It has a parietal and visceral layer. The parietal layer remains adhered to the scrotum while the visceral layer adheres to the capsule of the testis. The space between the these two layers is called the vaginal cavity. The layers consists of mesothelium lining and connective tissue that blends with the underlying connective tissue of the scrotum. Tunica albuginea: Capsule of the testis Consists of dense irregular connective tissue, predominantly collagen fibers, few elastic fibers and myofibroblast. It has vascular layer (Tunica vasculosa) that contains anatomizing branches of testicular artery and veins. The tunica albuginea gives connective tissue trabeculae called septula testis which converge towards the mediastinum testis. The septula testis divides the testicular parenchyma into number of testicular lobules. Each lobule contains 1-4 seminiferous tubules. Mediastinum testis is a connective tissue area containing the channels of rete testis, large blood and lymph vessels. In bull it occupies the central position along the longitudinal axis of the gonad. Interstitial cells (Leydig cells) The inter-tubular spaces of the testis contain loose C.T., blood and lymph vessels, fibrocytes, free mononuclear cells and interstitial cells called Leydig cells.
    [Show full text]
  • EFFECTS of RECOMBINANT HUMAN INTERFERON-Α-2B on TESTICULAR MORPHOLOGY, TESTOSTERONE PRODUCTION and AROMATASE GENE in ALBINO RAT MODEL
    EFFECTS OF RECOMBINANT HUMAN INTERFERON-α-2b ON TESTICULAR MORPHOLOGY, TESTOSTERONE PRODUCTION AND AROMATASE GENE IN ALBINO RAT MODEL A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Anatomy By Salman Ahmed Farsi Kazi MBBS,M.Phil Department of Anatomy Faculty of Medicine & Allied Medical Sciences Isra University, Hyderabad, Sindh October 2016 EFFECTS OF RECOMBINANT HUMAN INTERFERON-α-2b ON TESTICULAR MORPHOLOGY, TESTOSTERONE PRODUCTION AND AROMATASE GENE IN ALBINO RAT MODEL By Salman Ahmed Farsi Kazi MBBS,M.Phil Name Supervisor/Co-supervisors Prof. Dr. M. Ghiasuddin Shah Rashdi Ph.D Prof. Dr Fatehuddin Khand Ph.D Dr Jameel Ahmed Gandahi Ph.D DEDICATION This thesis is dedicated to my beloved mother and father My wife, kids and my teachers CERTIFICATE This is to certify that Dr Salman Ahmed Farsi Kazi s/o Muhammad Khan Kazi has carried out research work on the topic “Effects of Recombinant Human Interferon-α-2b on testicular morphology, testosterone production and aromatase gene in albino rat model” under my supervision and that his work is original and his thesis is worthy of presentation to Isra University for awarding the degree of “Doctor of Philosophy” in the subject of Anatomy. Prof. Dr. M. Ghiasuddin Shah Rashdi Supervisor _____________________ Signature of Supervisor iv ACKNOWLEDGEMENT With the deep and profound sense of gratitude and thanks to the almighty ALLAH for giving me the chance for completing this thesis, I am greatly indebted to my respected Supervisor, Professor Dr Ghiasuddin Shah Rashdi and Co-supervisors Professor Dr Fatehuddin Khand and Dr Jameel Ahmed Gandahi for their cooperation, guidance and constructive criticism in the successful completion of this thesis and without their help, this manuscript was not possible to complete.
    [Show full text]
  • Degeneration of the Germinal Epithelium Caused by Severe Heat Treatment Or Ligation of the Vasa Efferentia P
    Plasma FSH, LH and testosterone levels in the male rat during degeneration of the germinal epithelium caused by severe heat treatment or ligation of the vasa efferentia P. M. Collins, W. P. Collins, A. S. McNeilly and W. N. Tsang *Department ofZoology, St. Bartholomew''s Medical College, Charterhouse Square,London; XDepartment of Chemical Pathology, St. Bartholomew''s Hospital, London E.C.I, U.K.; and Department ofObstetrics andGynaecology, King's Hospital MedicalSchool,London, S.E.5, U.K. Summary. Rats were treated by exposure of the scrotum to a temperature of 43\s=deg\C for 30 min or bilateral ligation of the vasa efferentia and bled at 0, 3, 7,14 and 21 days after treatment. In heat-treated rats FSH levels rose linearly from pretreatment levels while those in efferentiectomized animals remained unchanged for 3 days before increasing. In both groups FSH concentrations reached similar maximum values after 7 days and were significantly higher than those of intact controls at 7, 14 and 21 days. LH levels, although not generally different from those in the controls, rose from pretreatment levels in parallel with FSH. No differences were found in testosterone concentrations in any of the groups. Histological examination at 3 weeks after treatment confirmed that the germinal epithelium consisted mainly of spermatogonia and Sertoli cells. The cytological appearance and lipid content of the Leydig cells of the aspermatogenic testes were indistinguishable from those of the controls and the weight and histological appearance of the accessory sex organs and the fructose content of the coagulating glands were also normal.
    [Show full text]
  • Endocrinology of the Testis Vas Efferentia Seminiferous Tubule 6-12 Tubules
    Structure of Spermatic Cord the Testis Vas Deferens Caput Epididymis Endocrinology of the Testis Vas Efferentia Seminiferous Tubule 6-12 tubules John Parrish Tunica Albuginea Corpus Epididymis References: Williams Textbook of Endocrinology Rete Testis (within the mediastinum) Cauda Epididymis Seminiferous Mediastinum Tubule Rete Testis Spermatogonia Primary Spermatocyte Seminiferous Tubule Sertoli Cells Myoid Cells »Support spermatogenesis Secondary Spermatocyte Leydig Cells »Testosterone Round Spermatids synthesis Spermatozoa Basement Membrane The Testis Capillary Sertoli Cell Germ Cell Migration Migration begins by the 4 week of gestation in cow and human. 1 Migration from endoderm through mesoderm. XY Male Y Chromosome Circulating Androgen SRY, SOX9 Testes develop • Sex Hormone Binding Globulin - 44% • Albumin - 54% (1000 fold less affinity than Leydig Cells Sertoli Cells SHBG) Differentiate Differentiate • Free - 2% SF-1 SF-1 5a-red Bioavailable Testosterone = free + albumin bound Testosterone DHT AMH AR AR SHBG is made in Liver Development of AMHR Development ABP is made in Sertoli Cells of Wollfian penis scrotum and Ducts Degeneration of accessory Both also bind estradiol Mullerian Duct sex glands Undifferentiated Gonad AMH AMH 2 Differentiated Reproductive Tracts Testicular Development Mesonephric Duct Mesonephric Tubules Female Male (Wolffian Duct) Rete Tubules Mullerian Duct Tunica Undifferentiated Albuginea Sex Chords Mesonephric Tubules Primary Sex Chords in Fetal Testis Rete Tubules Pre-Sertoli - AMH Wolffian Duct Leydig Cells - Testosterone Mullerian Duct Primary, Epithelial or Medullary Sex Chords Tunica • Primordial germ cells Gonocyte Albuginea (gonocytes) • Pre-Sertoli Cells FSH on Sertoli Cells Hypothalamus • estradiol GnRH • inhibin Negative Feedback • ABP • tight junctions • growth factors • Hypothalamus Ant. Pituitary Negative Feedback of » Testosterone conversion to Estradiol Estradiol and Inhibin » Androgen receptor is less important Negative To • Anterior Pituitary LH FSH Epid.
    [Show full text]
  • Male Reproductive System
    MALE REPRODUCTIVE SYSTEM DR.M.SARWAR ZIA Assistant professor anatomy RMU OVERVIEW Male reproductive system consists of Testes Genital ducts Accessary sex glands penis Functions of testes:- Production of spermatozoa Secretion of testosterone Actions of testosterone Actions of dihydrotestosterone Genital ducts & accessary sex glands Testes Testes derived from three sources Intermediate mesoderm Mesodermal epithelium Primordial germ cells Decent of testes At approximately 26 weeks testes descend Gubernaculum Cryptorchidism Orchioplexy Maintenance of temperature of testes in the scrotum . Countercurrent heat exchange mechanism . Sweating . Dartos muscle . Cremaster reflex Testes Tunica albuginea Tunica vasculosa Mediastinum testes Testicular lobules (250) Seminiferous tubules Interstitial loose connective tissue Interstitial cells (Leydig) Straight tubules Rete testes Seminiferous tubules Each Seminiferous tubule is . 50 cm long (30 to 80 cm) . 150 to 250µm in diameter Seminiferous epithelium Tunica propria (peritubular tissue) Spermatogenic cells Sertoli cells Sertoli cells . Structure . Sertoli cells junctional complexes Sertoli cell to Sertoli cell junctional complexes Sertoli cell to Spermatid junction Sertoli cell to basal lamina Sertoli cells functions Provide support ,protection and nutrition to developing spermatogenic cells Exocrine and endocrine secretion . Androgen binding protein(ABP) . Inhibin . Mullerian inhibiting substance (MIS) Phagocytosis Establish blood testis barrier which protects the haploid
    [Show full text]
  • Spermatogenesis Following Male Germ-Cell Transplantation (Spermatogonia/Stem Cd/Testes/ Nsc Mice) RALPH L
    Proc. Nati. Acad. Sci. USA Vol. 91, pp. 11298-11302, November 1994 Developmental Biology Spermatogenesis following male germ-cell transplantation (spermatogonia/stem cd/testes/ nsc mice) RALPH L. BRINSTER* AND JAMES W. ZIMMERMANNt Laboratory of Reproductive Physiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 Contributed by Ralph L. Brinster, August 11, 1994 ABSTRACT In the adult male, a population of diploid essentially the only self-renewing cell type in the adult stem-cell spermatogonia continuously undergoes self-renewal capable of providing a genetic contribution to the next and produces progeny cells, which Initiate the complex process generation. of cellular differentiation that results in mature spermatozoa. Because ofthe unique characteristics and potential ofstem We report here that stem cells Isolated from testes of donor cell spermatogonia, the ability to recover these cells, manip- male mice will repopulate sterile testes when injected Into ulate them in vitro, and transfer them to another testis would seminiferous tubules. Donor cell spermatogenesis in recipient provide a valuable technique to study the process of sper- testes showed normal morphological characteristics and pro- matogenesis. Furthermore, modifications ofthese cells prior duced mature spermatozoa. This methodology, besides open- to transfer could influence the development ofeggs fertilized ing new avenues of basic research Into spermatog s and by spermatozoa arising from the altered stem cells. We stem-cell self-renewal, may prove useful as a tool for biomedical describe here the requisite first step in this approach, a science and biotechnology. method to transplant testis cells from one male to another, and we demonstrate that spermatogenesis occurs from donor The only source of potentially totipotent diploid cells in the cells in the recipient male.
    [Show full text]
  • Secretions of the Testis and Epididymis
    SECRETIONS OF THE TESTIS AND EPIDIDYMIS B. P. SETCHELL Biochemistry Department, A.R.C. Institute of Animal Physiology, Babraham, Cambridge In recent years, it has become apparent that the testis produces, in addition to the androgens, considerable amounts of another type of secretion which flows from the lumina of the seminiferous tubules through the rete testis into the epididymis. Here a large part of the fluid part of the secretion is reabsorbed, but additional compounds are added as the spermatozoa pass down the epididymal duct. In this paper, attention will be largely confined to the most recent findings concerning this latter secretion, as the earlier observations have been reviewed by Setchell (1970a) and Setchell & Waites (1971). Rate offlow and ionic composition The fluid which flows from the rete testis of all species so far examined (ram, bull, boar, rat, hamster, wallaby) is a low-protein fluid, isotonic with plasma but containing about three times as much potassium, less sodium and bicarbonate and more chloride than plasma or testicular lymph. The fluid leaves the testis at a rate of between 10 and 20 \g=m\l/g testis/hr, i.e. about 40 ml/day from a 200-g testis of a ram (Voglmayr, Scott, Setchell & Waites, 1967), but to keep these figures in proportion it should be remembered that this rate of flow is exceeded five- to tenfold by the flow of lymph from the testis (Lindner, 1963; Cowie, Lascelles & Wallace, 1964) and 1000-fold by the flow of blood through the testis (Setchell & Waites, 1964). Fluid leaves the rete testis continually and at a steady rate and normally contains between 0-3 and 1 IO6 spermatozoa/ml.
    [Show full text]