Adenylate deaminase deficiency

Carnitine deficiency Impaired j3-oxidation with lipid accumulation, see text Adenylate deaminase deficiency Impaired anaerobic tolerance. 

Fig. 1 Distribution of specific activities of adenylate deaminase In 34 normal human muscle biopsies as a function of the % area (or volume) occupied by type 2 fibers. Although the data show considerable scatter, the least-squares-fltted regression (solid line) indicates a nearly 3-fold higher specific activity in type 2 than in type 1 fibers The dashed curves show the 95% confidence limits for the regression line, while the dotted curves show the 90% tolerance limits (with 0.25) for the population, for use in evaluating individual cases. Shorni in circles are the values for three putative carriers the mother (M) and father (F) of a deficient male, and the son (S) of a deficient father. All three are below the lower tolerance limit for the papulation at the appropriate fiber-type distribution, although they are much higher than the levels encountered in deficient patients (<. 05 EU/mg protein). Note that normals, carriers, and deficients could not be discriminated statistically where type 2 fibers account for less than 25% of the biopsy area. Note also that one carrier (F) would have been Interpreted as normal on the basis of simple mean specific activity, or if he were assumed to have the usual fiber type distribution (45-60% type 2).

Fishbein, W.N., J.L. Griffin, K. Nagarajan, J.W. Winkert, and V.W. Armbrustmacher. 1979. Immunologic uniqueness of muscle adenylate deaminase and genetic transmission of the deficiency state. Clin. Res. 27 274A. 

In 1978 Fischbein et al, described 5 patients with a myo-adenylate deaminase (MAD) deficiency, which were detected during a histochemical screening of 250 consecutive muscle biopsies. The deficiency was confirmed by a biochemical assay of the enzyme. Clinically three of the patients complained of muscle cramping, in one case associated with postexercise fatigue. CK was only moderately elevated, the myogram showed minor abnormalities, in muscle there were histologically no or only slight alterations. These three patients didn t show any muscle weakness or atrophy. 

Adenosine also stimulates the adenylate cyclase of other tissues, including guinea pig cerebral cortex slices (Sattin and Rail, 1970), isolated bone cells (Peck et al., 1974), platelets (Mills and Smith, 1971), fetal rat brain cell cultures (Gilman and Schrier, 1972), and lymphocytes (Wolberg et al., 1975). It is of interest that adenosine increases the concentration of cAMP in lymphocytes, which inhibits their in vitro cytol-ysis of tumor cells. Inhibition of adenosine deaminase potentiates the effect of adenosine. It is supposed that the impairment of lymphocyte function in adenosine deaminase deficiency is possibly related to the stimulatory effect of adenosine on lymphocyte adenylate cyclase (Wolberg et al., 1975). In brain slices, adenosine is released during depolarization (Shimizu et al., 1970 Schultz and Daly, 1973a,b). 

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