Sarcoidosis associated with nephrocalcinosis in young children.

Three patients with nonpulmonary sarcoidosis had chronic erythema nodosum within the first 2 years of life. Each subsequently had renal sarcoidosis and nephrocalcinosis; hypercalcemia was documented in each patient and hypercalciuria in two patients. Treatment with prednisone was not uniformly successful in normalizing creatinine clearance. Nephrocalcinosis may be more common than previously reported in patients with sarcoidosis.

Luteinizing hormone-releasing hormone induces thyroxine release together with testosterone in the neotenic axolotl Ambystoma mexicanum.

In male neotenic axolotls Ambystoma mexicanum plasma concentrations of thyroxine (T4) and testosterone were increased following intravenous injection of 10 micrograms luteinizing hormone-releasing hormone. A dose of 50 micrograms influenced only plasma T4 levels. This observation suggests for the first time that a hypothalamic hormone is capable of stimulating the thyroidal axis in the neotenic axolotl.

Thyroxine and triiodothyronine in plasma and thyroids of the neotenic and metamorphosed axolotl Ambystoma mexicanum: influence of TRH injections.

Circulating levels of T3 and T4, as well as T3 and T4 content of the thyroid glands were measured by radioimmunoassay in the neotenic and metamorphosed axolotl Ambystoma mexicanum. In the two experiments which were performed plasma T4 concentrations were more elevated in metamorphosed axolotls, especially in the first experiment (2.12 +/- 0.40 ng/ml vs. 369 +/- 30 pg/ml). T3 plasma values which were only estimated in the second experiment were about five times higher in metamorphosed animals (63.2 +/- 7.4 pg/ml vs. 12.5 +/- 0.8 pg/ml). Also the thyroid hormone content of the glands was higher after metamorphosis. Nevertheless the neotenic gland still contained considerable amounts of T3 (14.7 +/- 1.8 ng and 48.3 +/- 4.8 ng/thyroid, respectively, in the first and second experiment) and T4 (530 +/- 61 ng; 2173 +/- 291 ng/thyroid). Because of the higher T3/T4 ratio found in the plasma compared to the thyroid gland, it was suggested that circulating T3 may be derived partly from peripheral T4 conversion, mainly after metamorphosis. An intravenous injection of 10 micrograms synthetic TRH was able to induce a very significant increase of the plasma T4 concentration (which was maintained during 24 hr) in the metamorphosed axolotls of the first experiment, however, not in those of the second experiment nor in the neotenic animals. Following an injection of 10 mU bovine TSH (first experiment) circulating levels of T4 were raised in both groups. The opposing TRH results could be related with the different control levels of T4 in the two experiments. However, the results indicate that TRH is capable of functioning as a possible thyrotropin-releasing factor in the metamorphosed axolotl.