Secretions of the Testis and Epididymis

Total Page:16

File Type:pdf, Size:1020Kb

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. The number of spermatozoa can be dramatically reduced about 20 days after heating the testis to about body temperature for 1 to 3 hr without affecting or only slightly reducing the flow of fluid, and without apparently affecting its composition (Setchell, Voglmayr & Hinks, 1971; Setchell & Waites, 1972). However, the fluid leaving the rete testis is not exactly representative of the fluid inside the seminiferous tubules. Fluid removed from the tubules by micro- puncture contains more spermatozoa and potassium and less sodium and chloride than rete testis fluid (Tuck, Setchell, Waites & Young, 1970; Levine & Marsh, 1971). Furthermore, the fluid which is secreted into a droplet of oil in a seminiferous tubule (so-called 'primary fluid') contains even more potassium and less sodium and chloride, i.e. its composition approaches that ofintracellular fluid (Tuck et al., 1970). It would therefore appear that two fluid secretions are involved. Firstly, in the seminiferous tubules, there is a potassium- and bicarbon¬ ate-rich secretion which is then mixed with that from the rete testis epithelium. This second secretion probably contains sodium and chloride in plasma-like concentrations ; if this assumption is made, then it can be calculated from the 165 Downloaded from Bioscientifica.com at 09/29/2021 11:33:00AM via free access 166 . P. Setchell potassium or sodium concentrations of primary and rete testis fluid that the ratio of the volume of tubular to rete secretion is about 1:10. A value of this order for this ratio is also suggested by the concentration of spermatozoa in tubular and rete testis fluid in the rat (Tuck et al., 1970; Levine & Marsh, 1971 ; Setchell & Waites, 1972) and also from the calculated concentration of sper¬ matozoa in the total fluid trapped inside the testis by efferent duct ligation (Setchell, Duggan & Evans, 1973). Mechanism of secretion and its control The earlier observations by Barack (1968) and Setchell & Linzell (1968) suggested that the flow ofrete testis fluid was not affected by gonadotrophins and secretion is not immediately affected by hypophysectomy (Setchell, 1970b). However, Burgos & Vitale-Calpe (1969) reported that ovine luteinizing hor¬ mone (LH), injected into anaesthetized hamsters in enormous doses, caused increases in flow from a catheter in the rete testis. We were not able to confirm their observations, reproducing the dose of LH and other conditions as closely as possible, but using the weight gain of the testis after efferent duct ligation to measure fluid secretion (Setchell et al., 1973), and it would appear that Burgos & Vitale-Calpe's results were probably due to the expression of pre-formed fluid. In any case, they found that flow from their rete testis catheters declined during their periods of observation, in contrast to our observations of continuing and steady flow offluid in animals of many other species, both anaesthetized and conscious. Vitale-Calpe & Burgos (1970a, b) also suggested, from electron microscopical observations, that LH caused shedding of spermatozoa from the germinal epithelium. Again using a different technique, our results do not support this suggestion (Setchell et al., 1973). We counted the numbers of spermatozoa in rat and hamster testes, the efferent ducts of one testis of each animal being ligated (EDL) 10 hr previously, at which time half the animals were injected with LH. If LH were causing the release of spermatozoa from the germinal epithelium, then one would expect that there would be fewer spermatozoa in the unligated testes of the LH-injected animals than in the unligated testes of the albumin-injected controls, but no difference between the EDL testes, and there¬ fore a larger difference between the EDL and ligated testes after LH injection. This was not the case, and therefore we conclude that Vitale-Calpe & Burgos' results must have been due to unrepresentative sampling, always a problem when quantitative conclusions are drawn from the tiny samples examined under the electron microscope. Text-fig. 1. A diagram of the optical density along a disc gel after separating and staining the proteins of blood plasma, testicular lymph and rete testis fluid from a ram. Approxi¬ mately 50 /ig protein in 50 µ\ fluid were applied to the top of a 70 4 mm cylindrical 5-6% acrylamide gel pH 7-4 containing 0-5% sodium dodecyl sulphate which was run for 90 min at 60 V and 6 mA/gel. The gel was stained overnight with 0-25% naphthalene black in 25% isopropyl alcohol and 10% acetic acid, destained electrophoretically in 5% iso propylalcohol-7-5% acetic acid for 70 min, and then the optical density recorded with a Vitratron Densitometer (R. W. Evans, B. T. Hinton and B. P. Setchell, unpublished observations). Downloaded from Bioscientifica.com at 09/29/2021 11:33:00AM via free access 167 Relè testis fluid 2 3 Dislance along gel (cm) Downloaded from Bioscientifica.com at 09/29/2021 11:33:00AM via free access 168 . P. Setchell Proteins of rete testisfluid and seminiferous tubularfluid One of the most obvious features of rete testis fluid (RTF) is that, in contrast to testicular lymph and blood plasma, it contains very little protein. Moreover, it was apparent that the proteins which were present seemed to be partly similar to proteins in blood plasma and partly specific to RTF (Johnson & Setchell, 1968). These observations made with comparatively crude techniques have now been extended by Kormano, Koskimies & Hunter (1971) who examined both rete testis fluid and seminiferous tubular fluid, using step gel electrophoresis. They showed that many of the individual plasma proteins do not appear in rete testis fluid of the rat and that tubular fluid and to a lesser extent rete testis fluid contain a variety of specific proteins so that albumin constitutes a comparatively small fraction of the proteins in tubular fluid. This difference in the protein composition supports the idea of a dual origin of the fluids of the testis originally deduced from the different ionic composition (see above and Tuck et al., 1970), and it also means that immunological damage to the testis may be caused by antibodies entering the tubules, not across the blood-testis barrier which normally excludes proteins (Setchell, Voglmayr & Waites, 1969) but through the rete testis and the luminal surface of the germinal epithelium (Johnson, 1970, 1972). This idea is supported by the observation that the concentration of immuno¬ globulin is low in rete testis fluid (Johnson & Setchell, 1968) but is even lower in tubular fluid (Koskimies, Kormano & Lahti, 1971). Patterns for the proteins of Text-fig. 2. The enzyme activities per unit of protein in blood plasma and rete testis fluid compared with those from an aqueous extract of the testis in the ram. Note that the specific activity of many enzymes is higher in rete testis fluid than in blood plasma and the ratio ofthe activities in the fluid to that in the extract varies widely. Data from Suominen & Setchell (1972). AcG: N-acetyI-/3-glucosaminidase. AcP: acid phosphatase. ArS: arylsulphatase. AlkP: alkaline phosphatase. /3G1: /J-glucuronidase. G6PDH: glucose-6- phosphate dehydrogenase. G1DH : glutamate dehydrogenase. GOT : glutamate oxalacetate transaminase. GPT: glutamate pyruvate transaminase. ICDH: isocitrate dehydrogenase. LDH: lactate dehydrogenase. MDH: malate dehydrogenase. PK: pyruvate kinase. SDH: sorbitol dehydrogenase. Am pep: aminopeptidase. Amyl: -amyiase. Est: non¬ specific esterases. Hyal : hyaluronidase. Downloaded from Bioscientifica.com at 09/29/2021 11:33:00AM via free access Secretions of the testis and epididymis 169 human tubular fluid are similar to those for rat tubular fluid and show a number of specific proteins (Koskimies, Kormano & Alfthan, 1973). Rete testis fluid from rams and boars has also been analysed using 'disc', step gel and 'gradipore' electrophoresis and the presence of a number of specific proteins confirmed (R. W. Evans, B. T. Hinton and B. P. Setchell, unpublished observations, Text-fig. 1). Enzymes in rete testisfluid Some observations have also been made on the enzymic activity ofthe proteins of ram rete testis fluid. Most of the enzymes normally found in blood plasma are also found in rete testis fluid, but in lower concentrations than in plasma because of the low protein concentration.
Recommended publications
  • Te2, Part Iii
    TERMINOLOGIA EMBRYOLOGICA Second Edition International Embryological Terminology FIPAT The Federative International Programme for Anatomical Terminology A programme of the International Federation of Associations of Anatomists (IFAA) TE2, PART III Contents Caput V: Organogenesis Chapter 5: Organogenesis (continued) Systema respiratorium Respiratory system Systema urinarium Urinary system Systemata genitalia Genital systems Coeloma Coelom Glandulae endocrinae Endocrine glands Systema cardiovasculare Cardiovascular system Systema lymphoideum Lymphoid system Bibliographic Reference Citation: FIPAT. Terminologia Embryologica. 2nd ed. FIPAT.library.dal.ca. Federative International Programme for Anatomical Terminology, February 2017 Published pending approval by the General Assembly at the next Congress of IFAA (2019) Creative Commons License: The publication of Terminologia Embryologica is under a Creative Commons Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0) license The individual terms in this terminology are within the public domain. Statements about terms being part of this international standard terminology should use the above bibliographic reference to cite this terminology. The unaltered PDF files of this terminology may be freely copied and distributed by users. IFAA member societies are authorized to publish translations of this terminology. Authors of other works that might be considered derivative should write to the Chair of FIPAT for permission to publish a derivative work. Caput V: ORGANOGENESIS Chapter 5: ORGANOGENESIS
    [Show full text]
  • Kidney, Renal Tubule – Dilation
    Kidney, Renal Tubule – Dilation Figure Legend: Figure 1 Kidney, Renal tubule - Dilation in a male B6C3F1 mouse from a chronic study. Dilated tubules are noted as tracts running through the cortex and outer medulla. Figure 2 Kidney, Renal tubule - Dilation in a male F344/N rat from a chronic study. Tubule dilation is present throughout the outer stripe of the outer medulla, extending into the cortex. Figure 3 Kidney, Renal tubule - Dilation in a male B6C3F1 mouse from a chronic study. Slight tubule dilation is associated with degeneration and necrosis. Figure 4 Kidney, Renal tubule - Dilation in a male F344/N rat from a chronic study. Tubule dilation is associated with chronic progressive nephropathy. Comment: Renal tubule dilation may occur anywhere along the nephron or collecting duct system. It may occur in focal areas or as tracts running along the entire length of kidney sections (Figure 1). 1 Kidney, Renal Tubule – Dilation Renal tubule dilation may occur from xenobiotic administration, secondary mechanisms, or an unknown pathogenesis (see Kidney – Nephropathy, Obstructive (Figure 2). Dilation may result from direct toxic injury to the tubule epithelium interfering with absorption and secretion (Figure 3). It may also occur secondary to renal ischemia or from prolonged diuresis related to drug administration. Secondary mechanisms of tubule dilation may result from lower urinary tract obstruction, the deposition of tubule crystals, interstitial inflammation and/or fibrosis, and chronic progressive nephropathy (Figure 4). A few dilated tubules may be regarded as normal histologic variation. Recommendation: Renal tubule dilation should be diagnosed and given a severity grade. The location of tubule dilation should be included in the diagnosis as a site modifier.
    [Show full text]
  • Anatomical and Morphological Study of the Kidneys of the Breeding Emu (Dromaius Novaehollandiae)
    Turkish Journal of Zoology Turk J Zool (2016) 40: 314-319 http://journals.tubitak.gov.tr/zoology/ © TÜBİTAK Research Article doi:10.3906/zoo-1506-21 Anatomical and morphological study of the kidneys of the breeding emu (Dromaius novaehollandiae) 1, 2 3 2 3 Katarzyna MICHAŁEK *, Danuta SZCZERBIŃSKA , Marta GRABOWSKA , Danuta MAJEWSKA , Maria LASZCZYŃSKA 1 Department of Physiology, Cytobiology, and Proteomics, Faculty of Biotechnology and Animal Husbandry, West Pomeranian University of Technology in Szczecin, Szczecin, Poland 2 Department of Poultry and Ornamental Bird Breeding, West Pomeranian University of Technology in Szczecin, Szczecin, Poland 3 Department of Histology and Developmental Biology, Pomeranian Medical University, Szczecin, Poland Received: 15.06.2015 Accepted/Published Online: 05.01.2016 Final Version: 07.04.2016 Abstract: We analyzed 16 kidneys obtained from 15-year-old emus, Dromaius novaehollandiae. Emus were kept at an experimental farm in Poland. The results showed that each kidney was composed of 3 parts: cranial, medial, and caudal divisions. Histological results demonstrated that the kidneys consisted of 2 zones: the cortex and the medulla. The cortex made up the majority of the kidney, while the medulla formed only a small portion of the organ. Proximal and distal tubules and 2 types of glomeruli (looped and loopless) were localized in the cortex. Each of these glomeruli was characterized by tightly arranged mesangial cells. Proximal and distal tubules had a distinctive simple low cuboidal epithelium. The luminal surface of the proximal tubules had a brush border membrane, formed by numerous microvilli. The renal medulla of emu kidneys formed irregularly positioned characteristic cones of different sizes.
    [Show full text]
  • 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]
  • PROSTATE and TESTIS PATHOLOGY “A Coin Has Two Sides”, the Duality of Male Pathology
    7/12/2017 PROSTATE AND TESTIS PATHOLOGY “A Coin Has Two Sides”, The Duality Of Male Pathology • Jaime Furman, M.D. • Pathology Reference Laboratory San Antonio. • Clinical Assistant Professor Departments of Pathology and Urology, UT Health San Antonio. Source: http://themoderngoddess.com/blog/spring‐equinox‐balance‐in‐motion/ I am Colombian and speak English with a Spanish accent! o Shannon Alporta o Lindsey Sinn o Joe Nosito o Megan Bindseil o Kandace Michael o Savannah McDonald Source: http://www.taringa.net/posts/humor/7967911/Sindrome‐de‐la‐ Tiza.html 1 7/12/2017 The Prostate Axial view Base Apex Middle Apex Sagittal view Reference: Vikas Kundra, M.D., Ph.D. , Surena F. Matin, M.D. , Deborah A. Kuban, M.Dhttps://clinicalgate.com/prostate‐cancer‐4/ Ultrasound‐guided biopsy following a specified grid pattern of biopsies remains the standard of care. This approach misses 21% to 28% of prostate cancers. JAMA. 2017;317(24):2532‐2542. http://www.nature.com/nrurol/journal/v10/n12/abs/nrurol.2013.195.html Prostate Pathology Inflammation / granulomas Categories Adenosis, radiation, atrophy seminal vesicle Biopsy Benign TURP HGPIN Unsuspected carcinoma is seen in 12% of Atypical IHC TURP cases. glands Prostatectomy Subtype, Gleason, Malignant fat invasion, vascular invasion Other malignancies: sarcomas, lymphomas Benign Prostate Remember Malignant Glands Lack Basal Glands Cells Basal cells Secretory cells Stroma 2 7/12/2017 Benign Prostatic Lesions Atrophy Corpora amylacea (secretions) Seminal Vesicle Acute inflammation GMS Basal cell hyperplasia Basal cell hyperplasia Granulomas (BPH) (BPH) coccidiomycosis Mimics of Prostate Carcinoma Atrophy. Benign Carcinoma with atrophic features Prostate Carcinoma 1. Prostate cancer is the most common, noncutaneous cancer in men in the United States.
    [Show full text]
  • Fluid on the Germinal Epithelium in the Rat Lynn M
    Effects of obstruction of the flow of seminiferous tubule fluid on the germinal epithelium in the rat Lynn M. C. Pilsworth, B. T. Hinton and B. P. Setchell Department ofPhysiology, A.R.C. Institute ofAnimal Physiology, Babraham, Cambridge CB2 4AT, UK. Summary. Blocking the lumen of a single seminiferous tubule by introducing a plug of non-toxic latex produced a lesion in that tubule, but not in immediately adjacent tubules. The lesion extended for up to 50 mm from the end of the latex. Nearest to the block the tubule was completely aspermatogenic; further along the tubule, the lesion was less severe, involving disorganization and reduction in germ cell numbers, with the cells showing vacuolation, pycnosis and karyolysis. Binucleate and giant cells were common, and cells were often exfoliated into the lumen. The lesion tended to increase in length with longer times after introduction of the plug, but there appeared to be no preferential involvement of the shorter segment of the tubule between the block and the rete. The transition from damaged to healthy tubule was abrupt. Introduction The blood-testis barrier controls the composition of the seminiferous tubule fluid, which is thought to be important for the nurture of germ cells. Its composition probably reflects the conditions within the adluminal compartment of the germinal epithelium in which meiosis is completed (Setchell, 1970, 1978, 1980; Setchell & Waites, 1975). In addition, a possible involvement of fluid in the entrainment of the spermatogenic wave has been suggested (Perey, Clermont & Leblond, 1961) and flow of fluid may be important in the regulation of spermatogenesis.
    [Show full text]
  • Universidad Católica De Santa Maria
    UNIVERSIDAD CATÓLICA DE SANTA MARIA FACULTAD DE CIENCIAS E INGENIERIAS BIOLOGICAS Y QUIMICAS PROGRAMA PROFESIONAL DE MEDICINA VETERINARIA Y ZOOTECNIA “Identificación ecográfica de quistes en rete testis de alpacas en edad reproductiva en la Asociación de Criadores de Alpacas Sector Phacco, Distrito de Pitumarca, Provincia de Canchis, Cusco 2013” “Sonographic identification of cysts in rete testis of alpacas reproductive age in Alpacas Breeders Association Sector Phacco, Pitumarca District, Canchis Province, Cusco 2013” Tesis presentada por la Bachiller: FERNANDA CAROLINA PRADO CAYO Para optar el Título Profesional de: MEDICO VETERINARIO Y ZOOTECNISTA AREQUIPA- PERÚ 2013 1 DEDICATORIA Dedico mi tesis a Dios, mis padres y a mi hermano que me acompañaron en todo momento, nunca me sentí sola porque los llevo en el corazón, gracias porque a pesar de la distancia siempre están aquí conmigo, porque se preocuparon tanto para que sea una profesional, gracias por su apoyo. 2 AGRADECIMIENTOS A Dios por ser mi guía cada día en mi vida diaria. A la Universidad Católica de Santa María por ser mi Alma Mater y el lugar que sentí como mi segundo hogar. Al Programa Profesional de Medicina Veterinaria y Zootecnia porque me brindo la confianza de realizar mi carrera profesional y desempeñarse así en la sociedad. A los Docentes, por compartir conmigo sus enseñanzas y su dedicación para lograr culminar mi carrera profesional. A mi Asesor Mg. Fernando Fernández Fernández por su apoyo incondicional durante el desarrollo de mi proyecto de investigación. A mis Jurados: Mg. Gary Villanueva Gandarillas, Mg. Guillermo Vásquez Rodríguez, Mg. Jorge Zegarra Paredes; por su dedicación, comprensión y enseñanzas que me aportaron durante este tiempo.
    [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]
  • Nomina Histologica Veterinaria, First Edition
    NOMINA HISTOLOGICA VETERINARIA Submitted by the International Committee on Veterinary Histological Nomenclature (ICVHN) to the World Association of Veterinary Anatomists Published on the website of the World Association of Veterinary Anatomists www.wava-amav.org 2017 CONTENTS Introduction i Principles of term construction in N.H.V. iii Cytologia – Cytology 1 Textus epithelialis – Epithelial tissue 10 Textus connectivus – Connective tissue 13 Sanguis et Lympha – Blood and Lymph 17 Textus muscularis – Muscle tissue 19 Textus nervosus – Nerve tissue 20 Splanchnologia – Viscera 23 Systema digestorium – Digestive system 24 Systema respiratorium – Respiratory system 32 Systema urinarium – Urinary system 35 Organa genitalia masculina – Male genital system 38 Organa genitalia feminina – Female genital system 42 Systema endocrinum – Endocrine system 45 Systema cardiovasculare et lymphaticum [Angiologia] – Cardiovascular and lymphatic system 47 Systema nervosum – Nervous system 52 Receptores sensorii et Organa sensuum – Sensory receptors and Sense organs 58 Integumentum – Integument 64 INTRODUCTION The preparations leading to the publication of the present first edition of the Nomina Histologica Veterinaria has a long history spanning more than 50 years. Under the auspices of the World Association of Veterinary Anatomists (W.A.V.A.), the International Committee on Veterinary Anatomical Nomenclature (I.C.V.A.N.) appointed in Giessen, 1965, a Subcommittee on Histology and Embryology which started a working relation with the Subcommittee on Histology of the former International Anatomical Nomenclature Committee. In Mexico City, 1971, this Subcommittee presented a document entitled Nomina Histologica Veterinaria: A Working Draft as a basis for the continued work of the newly-appointed Subcommittee on Histological Nomenclature. This resulted in the editing of the Nomina Histologica Veterinaria: A Working Draft II (Toulouse, 1974), followed by preparations for publication of a Nomina Histologica Veterinaria.
    [Show full text]
  • On the Morphology of the Renal Tubules of Vertebrates
    AUTHOR'S ABSTRACT OF THIS PAPER ISSUED BY THE BIBLIOQRAPHIC SERVICE NOVEMBER 10. ON THE MORPHOLOGY OF THE RENAL TUBULES OF VERTEBRATES G. CARL HUBER Department of Anatomy, University of Michigaa TWENTY-TWO FIGURES A comparative study of the renal tubules of the different classes of vertebrates was projected nearly twenty years ago, soon after publishing results of a study on the development and shape of the uriniferous tubules of the higher mammah.1 In this study, as projected, it was purposed to reconstruct the excre- tory tubules of the pronephros and mesonephros of certain of the lower vertebrates, including amphibia, and the metanephric tubules of certain reptiles, birds and mammalia. In the re- construction, by the Born wax plate method, of the pronephric tubules of a larval toad, and mesonephric tubules of an adult frog and the metanephric tubules of certain reptilia no great difficulty was experienced, and such reconstructions were made, somewhat over fifteen years ago in conjunction with Professor Ward J. MacNeal, sometime Instructor in this department. On attempting to reconstruct the metanephric tubules of birds, it was learned after unsuccessful trials that this was beyond the limits of the method, so also with endeavors to reconstruct the metanephric tubules of adult mammalia. The projected study, therefore, was abandoned for a time. The form of the adult, mammalian renal tubule was later ascertained by specially devised methods of teasing.? This special method of teasing has relatively recently been successfully used in an investigation of the form of the metanephric tubule of birds. I am in a position now, therefore, to present figures giving the morphology 1 Huber, G.
    [Show full text]
  • Respiration and Elimination of Nitrogenous Wastes Forms and Functions of Plants and Animals
    MODULE - 2 Respiration and Elimination of Nitrogenous Wastes Forms and Functions of Plants and animals 14 Notes RESPIRATION AND ELIMINATION OF NITROGENOUS WASTES Every living organism needs energy to perform various life activities, and the process of respiration fulfils this energy requirement. You have already learnt in the lesson on food and nutrition that animals take in high energy organic molecules in the form of food. During respiration, this food is broken down in the presence of oxygen and energy is released during respiration. Respiration also produces carbon dioxide, a toxic substance which is eliminated from the body. Thus, uptake of oxygen and removal of carbon dioxide is an essential requirement of all animals. At the same time numerous other toxic wastes such as ammonia, and urea are also produced in the tissues during various cellular activities. Such toxic wastes need to be removed from the body. In this lesson you will learn about removal of nitrogenous wastes and maintenance of water and salt balance in the body. OBJECTIVES After completing this lesson you will be able to : z define respiration, breathing, inspiration, expiration and vital capacity; z describe briefly the gaseous exchange in earthworm and cockroach; z describe the parts of respiratory system in the human body and mention their functions; z draw a labeled diagram of human respiratory system; z differentiate between breathing and respiration; and inspiration and expiration; z describe the mechanism of breathing and its regulation; z describe the exchange
    [Show full text]
  • Male Reproductive Organs Testes (Paired Gonads)
    Male Reproductive Organs Testes (paired Gonads) Penis Series of passageways . Epididymis . Ductus Deferens . Urethra Accessory Glands . Seminal vesicle . Prostate Functions • Paired Gonads (Testes) – Produce Spermatozoa (male germ cells) & Androgens (male sex hormones) •Penis– Copulatory organ • Series of passageways & ducts – To store the spermatozoa , ready for delivery to male copulatory organ • Male accessory glands – provide fluid vehicle for carrying spermatozoa Coverings Tunica Vaginalis Tunica Albuginea Tunica Vasculosa Outermost Layer . Tunica Albuginea (Dense connective tissue fibrous Memb.) – Consist of closely packed collagen Fibres with a few Elastic Fibres . form septa ,Project from Mediastinum Testis . Divide incompletely into pyramidal lobules with apex towards Mediatinum . Each Testis Approx-200 lobule . Each lobule has Approx1-4 seminiferous Tubules . Form loop to end in Straight tubule (20-30) • Straight tubules end up unite to form network (Rete testis) which gives off 15-20 efferent ductules • Space between tubules filled up by Loose connective tissue (collagen fibres & fibroblasts,macrophases , mast cells), blood vessels, Lymphatics & Interstitial cells of Leydig Seminiferous Tubules • Fill most of interior of Each Testes • Two types of cells • Germ cells (represent different stages of spermatogenesis) Spermatogonia (Type A & type B) Primary spermatocyte Secondary spermatocyte Spermatids Spermatozoa • Sustantacular cells (Sertoli) Mitosis Spermatogonium 44+X 44+X Type A +Y +Y Spermatogonium 44+X+ Y Type B Enlarge/Mitosis
    [Show full text]