] i was monitored in Fluo 3-acetoxymethyl esterloaded myotubes by either confocal microscopy or fluorescence microscopy, with the use of out-of-focus fluorescence elimination. The mass of IP 3 was determined by radioreceptor displacement assay. [Ca 2ϩ ] i changes after either aldosterone (10-100 nM) or testosterone (50-100 nM) were observed; a relatively fast (Ͻ2 min) calcium transient, frequently accompanied by oscillations, was evident with both hormones. A slow rise in [Ca 2ϩ ] i that reached its maximum after a 30-min exposure to aldosterone was also observed. Calcium responses seem to be fairly specific for aldosterone and testosterone, because several other steroid hormones do not induce detectable changes in fluorescence, even at 100-fold higher concentrations. The mass of IP 3 increased transiently to reach two-to threefold the basal level 45 s after addition of either aldosterone or testosterone, and the IP 3 transient was more rapid than the fast calcium signal. Spironolactone, an inhibitor of the intracellular aldosterone receptor, or cyproterone acetate, an inhibitor of the testosterone receptor, had no effect on the fast [Ca 2ϩ ] i signal or in the increase in IP 3 mass. These signals could mean that there are distinct nongenomic pathways for the action of these two steroids in skeletal muscle cells. steroid hormones; inositol 1,4,5-trisphosphate; calcium waves; nongenomic pathway STEROID HORMONES ARE CAPABLE of producing rapid (within 2 min) effects in several cell types (12,22,36). These rapid responses are not compatible with the classical mechanism of action proposed for these hormones, which involves binding to intracellular receptors, transcriptional processes, and protein synthesis (1, 20). Thus, for rapid steroid effects, the existence of membrane receptors for steroids has been proposed (2, 37). In skeletal muscle, steroid hormones have long been known to modulate gene expression, and hormones like testosterone have been related to both muscle hypertrophy (4, 25) and upregulation of a number of proteins (31). In particular, glucocorticoids and mineralocorticoids have been related to up-and downregulation, respectively, of sodium pumps in skeletal muscle (10), implying the presence of steroid hormone receptors in muscle cells. Because all these effects have been the result of chronic (hours to days) treatments, it would be interesting to know whether exposure to these hormones is also accompanied by fast nongenomic events.The signal transduction mechanism for the rapid action of steroids in some cellular models could be regulated by second messengers such as intracellular calcium ([Ca 2ϩ

Diffuse intestinal ganglioneuromatosis is a hamartomatous polyposis characterized by a disseminated, intramural or transmural proliferation of neural elements involving the enteric plexuses. It has been associated with MEN II, neurofibromatosis type 1 and hamartomatous polyposis associated with phosphatase and tensin homolog mutation. We report the case of a female patient with a history of a breast and endometrial tumor who presented in a colonoscopy performed for rectal bleeding diffuse ganglioneuromatosis, which oriented the search for other characteristic findings of Cowden syndrome given the personal history of the patient. The presence of an esophagogastric polyposis was also noted. Cowden syndrome is characterized by skin lesions, but it is rarely diagnosed by these lesions, because they are usually overlooked. Intestinal polyposis is not a major diagnostic criterion but it is very useful for early diagnosis. The combination of colonic polyposis and glucogenic acanthosis should orient the diagnosis to Cowden syndrome.

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