Case Study Of Foetal Leydig Cells

Testosterone is released from the leydig cells and circulates the body. Like estrogen, testosterone can enter the target cell, bypassing the cell membrane and is transported to the nucleus by a carrier protein. Testosterone is also a transcription factor in which testosterone binds to genes and influences the function. Depending on the type of cell, testosterone can be converted into another form before reaching the nucleus. Only about seven percent of circulating testosterone is converted to dihydrotestosterone (DHT) and less than one percent is converted to estrogen. Testosterone first takes effect in the womb, allowing male reproductive organs to differentiate from female organs. The presence or absence of testosterone determines whether a baby will be male or female. At the onset of maturity, testosterone also signals other cells in the testes to begin production of sperm. Secondary sex characteristics include hair distribution on the face and body, the deepening of the voice as testosterone causes a growth in the larynx, induced male pattern fat distribution, bone growth, increase in sex drive and behavior. The hypothalamus regulates the amount of testosterone circulating the body by releasing follicle stimulating hormone and luteinizing hormone (Nieschlag, Behre, and Nieschlag, 2012). Testosterone utilizes a negative feedback loop by acting upon the hypothalamus to inhibit GnRH release and on the pituitary

1. These enzymes are used by the sperm to create an opening in the corona radiata, zona pellucida, and plasma membrane of the oocyte for the sperm to pass through

*. Low levels of _____ in the female embryo allow the normal development of female sex organs.

Gigantism is abnormally large growth during childhood caused by excess growth hormone secreted by the anterior pituitary gland.

Hypothyroidism often causes a person to sleep a lot, but the person is still tired. The parathyroids are located within the thyroid, secrete parathormone, and controls levels of calcium and phosphates in the body. The parathyroids are also involved with controlling excitability levels (Morris and Maisto, 2002).

This complex organ can be found in upper right side of the abdomen. It is unique because it is a dual functioning organ. The first function is to control the body’s blood sugar level. The second function is to secrete insulin and glucagon. Lastly, I studied the testes of the fetal pig, which I found at the end of the scrotum under the skin. The teste are a key part in the process of secreting testosterone. After completing this section I began to dissect the last system of the pig.

Testosterone belongs to a class of male hormones called androgens that is vital for sexual and reproductive development. The National Institutes of Health regards “testosterone as the most important male hormone”(Rettner). Although the primary role of testosterone directly relates to males, women also produce testosterone at lower levels. Women’s total levels are about a “tenth to a twentieth of men’s levels”(Rettner). According to the Mayo Clinic, this hormone plays a role in sex drive, sperm production, fat distribution, red cell production, and maintenance of muscle strength and

The pituitary is stimulated to release growth hormone (GH) by growth hromone releasing hormone (GHRH) produced in the hypothalamus. It is inhibited from releasing growth hormone by growth hormone release-inhibiting hormone(GHRIH), also produced by the hypothalamus.

Many young children are vaccinated every day, but do you know what is in vaccines? Almost all vaccines have one ingredient in common: cells from aborted baby fetuses. The medical community needs to realize it is not appropriate to use fetus cells in vaccines for many reasons.

Growth hormone or somatotropin is the hormone involved in the disorder of acromegaly. Produced by somatotrophs in the anterior pituitary gland, it functions as a metabolic hormone and determinant of body size. Growth hormones functions mainly on growth effects but it also has other aiding purpose in different parts of the body such as mobilization of fats, blood level increase, glycogen breakdown and more. The chemical nature of this hormone is protein based, hence the name somatotropin. It is originally made in the hypothalamus where it is secreted, then passes through the anterior pituitary gland before it enters the bloodstream. It is regulated through negative feedback, inhibiting the release of growth hormones when the amount in the bloodstream is high already. In terms of target tissues, it is very general, pretty much all the bone structure and most of the muscular system is affected by the growth hormone. It also has a very short half-life, ranging from twenty to thirty minutes. Typically, growth hormones are secreted the most during sleep; however, it decreases with age. Growth hormones cannot be naturally conjugated due to its own ability to inhibit its release when it is too much in the body already.

Luteinizing hormone releasing hormone (LHRH) agonists therapy may be used to enhance a negative feedback loop between the anterior pituitary and testicles, thus inhibiting the production of TST. LHRH agonists replicate the effects of endogenous luteinizing hormone which cause an acute rise in TST production — followed by a significant decrease in long term TST levels. LHRH antagonists may be used to disrupt the hypothalamic pituitary axis and inhibit the production of male sex androgens. The therapeutical index of LHRH antagonists may be greater than that of LHRH agonists because they do not cause the acute flare in TST as

• Testosterone - a male hormone produced mainly in the testes. Testosterone causes the development of male sex characteristics, such as a deep voice and a beard. It also strengthens muscles and bone mass.

In class, we watched a film that informed us about the growing irregularities in male reproduction and the possible environmental changes that are associated with it. These changes are not only affecting humans but also several land and aquatic species. Using several experimentations and observations, scientists aim to trace the effect of estrogenic compounds in the environment on males. If we are not able to determine the cause and stop it, the process and its modifications on the male reproductive system may eventually result in male sterility.

Q1. This infant exhibits a genetic defect known as 21-hydroxylase deficiency classical congenital adrenal hyperplasia (CAH), which "is an inherited disorder that affects the adrenal glands" (What is 21-hydroxylase deficiency, 2010, NIH). The female infant in this case study exhibits the 'classic' form of the condition, resulting in ambiguous genitalia. "The adrenal glands are located on top of the kidneys and produce a variety of hormones that regulate many essential functions in the body. In people with 21-hydroxylase deficiency, the adrenal glands produce excess androgens, which are male sex hormones" (What is 21-hydroxylase deficiency, 2010, NIH). Females with the condition may exhibit male sex traits such hirsutism and pattern baldness as well as irregular menstruation and impaired fertility.

At the beginning of open biopsy, the skin over the testicle was cleaned with a germ-killing (antiseptic) medicine. The area around covered with a sterile towel. (As like what was done in onset of local anesthesia.) The testis was grasped between the thumb and forefinger of the non-dominant hand. An incision was then made over the same area immediately. The size of the incision was about over 0.5– 1cm . An vascular area close to midportion of medial, lateral or anterior surface of the testis was chosen, tunica albuginea incised longitudinally with a 150 ultrasharp knife. The testicular parenchyma (approximately 50-750 mg) was excised with sharp, curved scissors and placed in temperature-adopted Hams F10 culture medium supplemented with 10% Plasmanate. Wet preparations transferred to the in vitro fertilization (IVF) lab. Individual tubules were isolated by immediate initial dispersal of the specimen with two sterile glass slides. Mincing of the tissue with a sterile scissors in the Hams F10 medium additional allowed for mechanical dispersal and preparing sequential passes of tissue suspension (detection of fully condensed spermatids) through a 24-gauge angiocatheter. As soon as spermatozoa were identified, no further testicular incisions are made. To prevent devascularization of the testis from damage to the subtunical