UROGENITAL TRACT Dr. Sándor Katz

Urinary system - constituents

Kidney Weight: 130-140g

Kidneys - location On the posterior body wall Posterior to parietal peritoneum – retroperitoneal organ At the level of T12-L2

Kidneys - location The right kidney is lower than left.

Kidneys – covering structures Renal fascia Adipose capsule Fibrous capsule

Kidney – gross anatomy External structures: Hilum of kidney: (from anterior to posterior) Renal vein Renal artery Ureter Internal structures: Cortex Medulla Minor calices Major calices Renal pelvis

Kidney – histology: Nephron Structural and functional unit of kidney. Components: Renal corpuscle: Bowman’s capsule Glomerulus 2. Renal tubules: Proximal convoluted tubule Loop of Henle Distal convoluted tubule

Bowman’s capsule, Glomerulus Parietal layer: simple squamous epithelium Visceral layer: podocytes Glomerulus: - filters plasma Afferent arteriole Efferent arteriole (1200ml blood goes through the kidneys each minute. 125ml- glomerular filtration 124ml- reabsorbed glomerular filtration =1ml urine/min.)

Proximal and distal convoluted tubules Proximal convoluted tubule: Cuboidal cells with brush border. (Absorption: water, glucose, amino acids, Na+, vitaminC) Loop of Henle: Squamous epithelium. (Absorption: water, Na+, Cl-, Ca2+, PO4. Secretion: H+, K+.) Distal convoluted tubule: Cuboidal cells without brush border. (Absorption: water, Na+, Ca2+, HCO3- or H+. Secretion: K+, HCO3- or H+.)

Ureter Retroperitoneal 25-30cm long Shows frequent contractions Lined by urothelium

Urothelium Umbrella cells Pear shaped cells Basal cells

Urinary bladder Infraperitoneal organ Urinary trigone: ureteric openings, urethral opening Folds of mucous membrane over the openings of ureters Detrusor muscle Lined by urothelium Average capacity: 300ml

Ultrasound picture of bladder

Urethra Lined by stratified columnar epithelium. Female urethra: 2-3cm long Male urethra: 15-18cm long Represents 3 divisions: Prostate part Membranous part Spongy part

Pathology

Female reproductive system Internal constituents: Ovaries Fallopian tubes Uterus Vagina External constituents: Clitoris Labia minora 3. Labia majora

Female reproductive organs - location Infraperitoneal organs.

Ovary Connective tissue bed filled follicles with developing ova. Parts: Cortex Medulla (Women can ovulate between 10-50 years of age – 480 ovulation/reproductive period.)

Maturation of follicles 1. Primordial follicle: simple squamous epithelium 2. Primary follicle: simple cuboidal epithelium 3. Secondary follicle: stratified cuboidal epithelium 3.

Maturation of follicles 4. Graafian follicle

Fallopian tube Transports ova. Fimbriae Infundibulum Ampulla Isthmus

Uterus Fundus Body Cervix

Ligaments of uterus

Pouches of uterus Recto-uterine pouch or Douglas- pouch: Deepest point of female abdominal cavity. (fluid accumulation) Vesico-uterine pouch: No clinical relevances.

Uterus - wall Endometrium: 2. Myometrium: 3. Perimetrium: simple columnar epithelium, glands, blood vessels, connective tissue. Layers: functional: stratum compactum stratum spongyosum basal 2. Myometrium: smooth muscle 3. Perimetrium: peritoneum

Menstrual cycle Menstrual phase: loss of functional layer of endometrium. 2. Proliferative phase: development of functional layer of endometrium (glands, blood vessels) Secretory phase: preparation for the implantation of an embryo. If fertilization does not occur the menstrual flow begins.

Menstrual phase (Coiled arteries constrict – deprivation of endometrium from blood supply – discharge outer endometrium lining. Content of flow: blood, epithelium, connective tissue. Volume: 35-45ml. )

Vagina Receives secretion from uterus and penis during copulation. Pathway for fetus. Lined by stratified squamous epithelium.

External genitalia 1. Clitoris: 2 erectile bodies 2. Labia majora: folds of skin 3. Labia minora: folds of skin. No hair.

Pathology Cervix cancer

Male reproductive organs Internal components: Gonad – testis Duct – system: epididymis, deferent duct, ejaculatory duct Additional glands: seminal vesicle, prostate gland, bulbourethral gland External component: Penis

Testis Location: in a skin pouch- scrotum. Forms sperm. Produces testosterone. Connective tissue capsule. Connective tissue septa – lobules. Lobules contain 2-3 seminiferous tubules.

Testis - histology Germinal epithelium – changing characteristic – sperm. Sertoli cell: Supporting function, maintains hormone level, blood-testis-barrier. Leydig cell: Produces testosterone.

Epididymis Stores sperm. Lined by pseudostratified columnar epithelium.

Deferent duct 45 cm long. Contracts during ejaculation.

Spermatic cord Contents: Deferent duct Deferential vessels Testicular artery Pampiniform plexus Genital branch of genitofemoral nerve Cremasteric muscle Cremasteric vessels Sympathetic and parasympathetic nerves

Seminal vesicle 60% of semen. Fructose secretion.

Prostate gland 15-30% of semen. Acids secretion – activates sperm.

Bulbourethral glands Location: urogenital diaphragm. Secretes viscous fluid – lubrication of the urethra.

Penis

Penis 2 corpora cavernosa – blood sinuses 1 corpus spongiosum - urethra

Steps of erection Sexual stimulus Relaxation of the smooth muscle in cavernous space and arterioles Blood inflow (50ml) to the cavernous space Occlusion of the venous drainage Intracavernous blood pressure > systemic blood pressure ERECTION

Rectovesical pouch Deepest point of male abdominal cavity. No relevances.

Thank you for attention! References: Gray’s Anatomy for Students Elsevier, Kierszenbaum: Histology and Cell Biology: An Introduction to Pathology 2e LWW: Langman’s Medical Embryology WebPathology.com