Kidney androgens

Androgen Kidney -Glucuronidase Acid phosphatase Plaut and Fishman (1963)... 

Older adults with cardiac problems or kidney disease are at increased risk for sodium and water retention when taking the androgens or anabolic steroids. 

The adult male prostate contains abundant acid phosphatase which it secretes into the semen. The production of this enzyme is governed by the circulating levels of androgenic hormones. Castration or estrogen administration markedly reduces the prostatic urinary acid phosphatase of males. Other organs such as the liver, kidney, spleen, red cells and platelets also contain significant amounts of acid phosphatase. 

Flutamide is an androgen receptor antagonist that achieves peak concentrations approximately 2 to 4 hours after an oral dose. Flutamide is metabolized extensively, with a terminal half-life of about 8 hours. Bicalutamide achieves peak concentrations approximately 6 hours after the dose, with a terminal half-life of 6 to 10 days. Bicalutamide undergoes stereospecihc metabolism, where the S-enantiomer is cleared more rapidly by the liver than the -enantiomer. Nilutamide achieves peak serum concentrations between 1 to 4 hours after an oral dose and has a terminal half-life of 38 to 60 hours. Nilutamide is metabolized extensively, with less than 2% excreted as unchanged drug by the kidney. Side effects common to these agents are hot flashes, gynecomastia, and decreased libido. Flutamide tends to be associated with more diarrhea and requires three-times-daily administration, whereas bicalutamide is dosed once daily. Nilutamide may cause interstitial pneumonia and is associated with the visual disturbance of delayed adaptation to darkness. 

Isern, J., et al. Functional analysis and androgen-regulated expression of mouse organic anion transporting polypeptide 1 (Oatpl) in the kidney. Biochim. Biophys. Acta 2001, 1518, 73-78. 

Hormones are intercellular messengers. They are typically (1) steroids (e.g., estrogens, androgens, and mineral corticoids, which control the level of water and salts excreted by the kidney), (2) polypeptides (e.g., insulin and endorphins), and (3) amino acid derivatives (e.g., epinephrine, or adrenaline, and norepinephrine, or noradrenaline). Hormones maintain homeostasis—the balance of biological activities in the body for example, insulin controls the blood glucose level, epinephrine and norepinephrine mediate the response to the external environment, and growth hormone promotes normal healthy growth and development. 

The catabolism of plasma testosterone and other androgens occurs primarily in the liver (Fig. 63.3), where they are conjugated into water-soluble compounds that are excreted by the kidney as the urinary 17-ketosteroids. 

The protein anabolic actions of androgens on bone and skeletal muscle are responsible for the larger stature of males than females. Androgens induce some degree of anabolism in other tissues, including bone marrow, liver, kidney, and heart. They also have several other actions, not necessarily associated with maleness, such as lymphoid tissue regression during puberty. 

Figure 12.1 Anabolic-androgenic steroids, such as Depo -Testosterone, are often injected directly into muscle tissue. In teens, steroid use can slow or halt bone growth and damage the heart, kidneys, and liver.

Kidney tumors caused by several different compounds, including 1,4-dichlorobenzene, isophorone, and unleaded petrol, have been found to be both sex dependent and species dependent. Thus, only male rats suffer from oc2-p-globulin nephropathy and renal tubular adenocarcinoma as a result of the accumulation of a compound-protein complex in the epithelial cells of renal proximal tubules (see chap. 6). The synthesis of the protein involved, a2-[i-globulin, is under androgenic control in the male rat. 

A sex difference in the toxicity of chloroform to the kidney occurs in mice. Male animals are more sensitive than females. The reason is that chloroform is metabolized more rapidly in male mice than females and this is affected by male hormones (androgens). 

Anemia. Testosterone and similar compounds are potent stimulators of erythropoietin synthesis from the kidneys and other tissues.109 Erythropoietin, in turn, stimulates production of red blood cell synthesis in bone marrow. Human erythropoietin, however, can now be synthesized using recombinant DNA techniques. Hence, various types of anemia that occur secondary to renal disease, cancer chemotherapy, and so forth are usually treated directly with recombinant erythropoietin.109 Nonetheless, androgens may be used as an adjunct to erythropoietin and other drugs to stimulate red blood cell production in certain patients with severe or recalcitrant anemia.10... 

Mastomys is an African rodent that is intermediate in size and that has physical characteristics between the mouse and rat. It has been studied because of the presence of an androgen-responsive prostate in the female. Fahnestock reported the cloning of cDNAs from Mastomys. Two of these cDNAs were expressed in the kidney as well as the submandibular gland, and one is hypothesized to code for a true tissue kallikrein [22]. A third kallikrein was found only in the submandibular gland. DNA sequence analysis and hybridization studies demonstrate that Mastomys represents an interesting hybrid between mouse and rat [22],... 

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