Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The haemodynamic effects of different dosages of adenosine were studied using colour flow Doppler sonography (CFDS) in 33 men, whose penile vascular bed responded well to papaverine. In six cases, we injected 25, 50, 100, 250 micrograms dosages of adenosine intracavernously at 15 min intervals and no erection occurred. However, 500 and 1000 micrograms doses of adenosine increased the arterial blood velocities for a few seconds in five cases. Later on, in eight cases, we infused 80 and 120 micrograms/kg/min adenosine for 3 min and only with 120 micrograms/kg/min dosage, did we observe clinical response and significant changes in CFDS parameters. Finally, 120 micrograms/kg/min adenosine dosage was infused for 10 min in 14 men and eight showed full erection while six had only tumescence. As adenosine was rapidly metabolized by adenosine deaminase, the erection lasted for only 5 to 13 min. No prolonged erection and no other side-effect was observed. In addition no fibrosis and curvature was detected 6 months after the injections. We found that, in men, 10 min infusion of 120 micrograms/kg/min adenosine increased the arterial flow and to some extent venous resistance, resulting in full erection or tumescence. Therefore, adenosine may be used as an agent for the diagnosis of vasculogenic impotence, but further studies for determining the standard dosage of adenosine are needed.
 ...
PMID:Adenosine: a new agent in the diagnosis of impotence. 779 19

L-arginine is conditionally essetcial amino acid, required for normal cell growth, protein synthesis, ammonia detoxification, tissue growth and general performance, proposed in the treatment of men sterility and prevention of male impotence. The aim of the present paper was to estimate the activity of the enzymes of adenine nucleotide metabolism: 5'-nucleotidase (5'-NU), adenosine deaminase (ADA), AMP deaminase, and xanthine oxidase (XO), during dietary intake of L-arginine for a period of four weeks of male Wistar rats. Adenosine concentration in tissues is maintained by the relative activities of the adenosine-producing enzyme, 5'-NU and the adenosine-degrading enzyme-ADA adenosine deaminase. Dietary L-arginine intake directed adenine nucleotide metabolism in liver, kidney, and testis tissue toward the activation of adenosine production, by increased 5'-NU activity and decreased ADA activity. Stimulation of adenosine accumulation could be of importance in mediating arginine antiatherosclerotic, vasoactive, immunomodulatory, and antioxidant effects. Assuming that the XO activity reflects the rate of purine catabolism in the cell, while the activity of AMP deaminase is of importance in ATP regeneration, reduced activity of XO, together with the increased AMP-deaminase activity, may suggest that adenine nucleotides are presumably directed to the ATP regenerating process during dietary L-arginine intake.
 ...
PMID:L-arginine intake effect on adenine nucleotide metabolism in rat parenchymal and reproductive tissues. 2262 85