What Is The Function Of The Blood Testis Barrier?

Thus, the function of the blood-testis barrier is to sequester germ cells residing in the adluminal compartment from the circulatory and lymphatic systems, and together with local immune suppression , to provide an immunoprivileged microenvironment for the completion of meiosis (for reviews, see Refs. 18–21).

What is blood-testis barrier definition?

The blood–testis barrier is a physical barrier between the blood vessels and the seminiferous tubules of the animal testes .

What does the blood-testis barrier separate?

The blood-testis barrier (BTB) is one of the tightest blood-tissue barriers in the mammalian body. It divides the seminiferous epithelium into the basal and the apical (adluminal) compartments .

What do the Sustentacular cells secrete?

Sertoli cells secrete various proteins , including androgen-binding protein, as well as hormones such as inhibin and anti-Müllerian hormone (in the fetus; see Chapter 5). These cells produce enzymes that convert testosterone to estrogen and to 5α-dihydrotestosterone (DHT).

What is the function of the specialized tight junctions between adjacent Sertoli cells?

Within the mammalian testis, specialized tight junctions between somatic Sertoli cells create basal and apical polarity within the cells, restrict movement of molecules between cells, and separate the seminiferous epithelium into basal and adluminal compartments .

What is rated testis?

The rete testis (/ˈriːti ˈtɛstɪs/ REE-tee TES-tis) is an anastomosing network of delicate tubules located in the hilum of the testicle (mediastinum testis) that carries sperm from the seminiferous tubules to the efferent ducts. It is the counterpart of the rete ovarii in females.

What is the blood brain barrier?

The blood-brain barrier (BBB) is a crucial immunological feature of the human central nervous system (CNS). Composed of many cell types, the BBB is both a structural and functional roadblock to microorganisms, such as bacteria, fungi, viruses or parasites, that may be circulating in the bloodstream.

What maintains the blood-testis barrier?

The blood-testis barrier is stabilized by a large number of component proteins including subsurface actin filaments and actin-binding proteins such as espin .

What are the steps in spermiogenesis?

Spermiogenesis is comprised of four phases. These phases are (1) Golgi phase, (2) Cap phase, (3) Tail phase, and (4) Maturation phase . Following spermiogenesis is spermiation. The spermatozoa are released from the seminiferous tubules to migrate to epididymis where they become fully-differentiated, motile spermatozoa.

What is Adluminal compartment?

In the adluminal compartment, spermatocytes derived from spermatogonia in the basal compartment undergo meiosis to form spermatids that progressively mature (spermiogenesis), with the more mature germ cells occupying positions closer to the lumen, until mature spermatozoa are released into the lumen of the tubule ( ...

What is the main function of Sertoli cells?

Sertoli cells facilitate the progression of germ cells to spermatozoa via direct contact and by controlling the environment milieu within the seminiferous tubules . The regulation of spermatogenesis by FSH and testosterone occurs by the action of these hormones on the Sertoli cells.

What stimulates Leydig cells?

Luteinizing hormone (LH) secreted by the pituitary gland in response to gonadotropin-releasing hormone (GnRH) from the hypothalamus, initiates steroid formation by binding to the Leydig cell LH receptor (LHR) which, through coupling to G protein, stimulates Leydig cell cyclic adenosine 3′,5′-monophosphate (cAMP) ...

Do females have Sertoli cells?

The Sertoli cells are normally located in the male reproductive glands (the testes). They feed sperm cells. The Leydig cells, also located in the testes, release a male sex hormone. These cells are also found in a woman’s ovaries, and in very rare cases lead to cancer.

What is a primary Spermatocyte?

: a diploid spermatocyte that has not yet undergone meiosis .

What is Type A and Type B spermatogonia?

There are three subtypes of spermatogonia in humans: Type A (dark) cells, with dark nuclei . These cells are reserve spermatogonial stem cells which do not usually undergo active mitosis. ... Type B cells, which undergo growth and become primary spermatocytes.

What do nurse cells produce?