Hypogonadism, Pituitary

Chorionic gonadotropin (HCG) is extracted from human placentas. The actions of HCG are identical to those of the pituitary LH. The hormone is used to induce ovulation in anovulatory women. This drug is also used for the treatment of prepubertal cryptorchism (failure of the testes to descend into the scrotum) and in men to treat selected cases of hypogonadotropic hypogonadism. 

Damage and destruction of the pituitary gland may result in secondary hypothyroidism, hypogonadism, adrenal insufficiency, growth hormone deficiency, hypoprolactinemia, or... 

Routinely assess acromegaly complications, including blood pressure, glucose tolerance, fasting lipid profile, cardiac evaluations (if clinically indicated), colonoscopy, dual-energy x-ray absorptiometry (DEXA) scan (hypogonadal only), evaluation of residual pituitary function, and evaluation of sleep apnea. 

Endocrine disorders (hypogonadism and pituitary, adrenal, and thyroid disorders)... 

Causes of organic ED include diseases that compromise vascular flow to the corpora cavernosum (e.g., peripheral vascular disease, arteriosclerosis, essential hypertension), impair nerve conduction to the brain (e.g., spinal cord injury, stroke), and are associated with hypogonadism (e.g., prostate or testicular cancer, hypothalamic or pituitary disorders). 

Habiby, R. L., Boepple, P., NachtigaU, L., Sluss, P. M., Crowley, W. F., and Jameson, J. L. (1996) Adrenal hypoplasia congenita with hypogonadotropic hypogonadism—evidence that DAX-1 mutations lead to combined hypothalamic and pituitary defects in gonadotropin production. J. Clin. Invest. 98, 1055-1062. 

Hypogonadotropic hypogonadism (congenital or acquired) Idiopathic gonadotropin or luteinizing hormone releasing hormone (LHRH) deficiency or pituitary-hypothalamic injury from tumors, trauma, or radiation. 

Testicular failure may occur before puberty and present as delayed puberty and the eunuchoid phenotype, or after puberty, with the development of infertility, impotence, or decreased libido in otherwise fully virilized males. The source of hypogonadism can be testicular, as occurs in primary hypogonadism, or it may result from abnormalities of the hypothalamic-pituitary axis, as in secondary hypogonadism. 

DES is a synthetic estrogen that inhibits ovulation by affecting release of pituitary gonadotropins. Some of its uses include treatment for hypogonadism, primary ovarian... 

Ironically, sustained non-pulsatile administration of GnRH or GnRH analogs inhibits the release of FSH and LH by the pituitary in both women and men, resulting in hypogonadism. 

GnRH can stimulate pituitary function and is used to treat infertility caused by hypothalamic hypogonadotropic hypogonadism in both sexes. A portable battery-powered programmable pump and intravenous tubing allows pulsatile GnRH therapy every 90 minutes. 

FSH or hMG are indicated for pituitary or hypothalamic hypogonadism with infertility. 

Androgenic effects Androgenic steroids are used in males with inadequate androgen secretion. [Note Hypogonadism can be due to Leydig cell dysfunction or, secondarily, to failure of the hypothalamic-pituitary unit. In each instance, androgen is indicated.]... 

The penis has two corpora cavernosa, which have many interconnected sinuses that fiU with blood to produce an erection. The penis also has one corpus spongiosum, which surrounds the urethra and forms the glans penis. Acetylcholine works with other neurotransmitters (i.e., cyclic guanylate monophosphate, cyclic adenosine monophosphate, vasoactive intestinal polypeptide) to produce penile arterial vasodilation and ultimately an erection. Causes of organic ED include diseases that compromise vascular flow to the corpora cavernosum (e.g., peripheral vascular disease, arteriosclerosis, essential hypertension), impair nerve conduction to the brain (e.g., spinal cord injury, stroke), and are associated with hypogonadism (e.g., prostate or testicular cancer, hypothalamic or pituitary disorders). 

Hypogonadotropic hypogonadism occurs when defects in the hypothalamus or pituitary prevent normal gonadal stimulation. Causative factors include congenital or acquired panhypopituitarism, hypothalamic syndromes, GnRH deficiency, hyperprolactinemia, malnutrition or anorexia, and... 

Decreased concentrations of 17-KSs usually are found in men with primary hypogonadism (Klinefelter s syndrome and castration), in secondary hypogonadism (panhypopituitarism), and in women with pituitary hypoadrenahsm (Addison s disease). Increased concentrations are found in patients with testicular tumors (interstitial cell tumor and chorioepithelioma), adrenal hyperplasia, and adrenal carcinoma, and in some women with hirsutism. 

Bromocriptine Alcohol Bromocriptine is an ergot alkaloid and a dopamine receptor D2 agonist that inhibits prolactin release from the pituitary gland [228]. Bromocriptine is typically used to treat Parkinsonian syndrome as well as hyperprolactinaemia, growth hormone- and prolactin-related disorders such as menstrual disorders, infertility, and hypogonadism. 

Destruction of the pituitary gland may result in secondary hypothyroidism, hypogonadism, adrenal insufficiency, growth hormone deficiency, and hypoprolactinemia. The formation of certain types of pituitary tumors may result in pituitary hormone excess. Pituitary tumors may also physically compress the pituitary and prevent the release of the trophic hypothalamic factors that regulate pituitary hormones. In this chapter, the pathophysiology and role of pharmacotherapy in the treatment of acromegaly, short stature, hyperprolactinemia, and panhypopituitarism will be discussed. 

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