Search

In vitro studies have demonstrated that thyroid hormones can enhance basal and stimulated growth hormone secretion by cultured pituitary cells. However, both in man and in the rat the effects of high thyroid hormone levels on GH secretion are unclear. The aim of our study was to test the GH response to human GHRH in hyperthyroid patients and to evaluate the effects on GH secretion of short- and long-term pharmacological decrease of circulating thyroid hormones. We examined 10 hyperthyroid patients with recent diagnosis of Graves' disease. Twelve healthy volunteers served as controls. All subjects received a bolus iv injection of GHRH(1-29)NH2, 100 μg. Hyperthyroid patients underwent a GHRH test one and three months after starting antithyroid therapy with methimazole, 10 mg/day po. GH levels at 15, 30, 45, 60 min and GH peak after stimulus were significantly lower in hyperthyroid patients than in normal subjects. The GH peak was also delayed in hyperthyroid patients. After one month of methimazole therapy, most of the hyperthyroid patients had thyroid hormone levels in the normal range, but they did not show significant changes in GH levels after GHRH, and the GH peak was again delayed. After three months of therapy with methimazole, the hyperthyroid patients did not show a further significant decrease in serum thyroid hormone levels. However, mean GH levels from 15 to 60 min were significantly increased compared with the control study. The GH peak after GHRH was also earlier than in the pretreatment study. In conclusion, the GH response to GHRH is inhibited and delayed by hyperthyroidism and returns to the normal pattern after long-term euthyroidism has been achieved with methimazole.

Salmon calcitonin (sCT) is biologically effective when intranasally (i.n.) administered. CT is the treatment of choice for Paget's disease; however, the chronic nature of the disease makes parenteral administration uncomfortable due to the high incidence of adverse reactions occurring after CT injection. The aim of our study was to investigate the efficacy, safety and tolerability of a sCT i.n. spray in the long-term treatment of Paget's disease. Ten pts (4M,6F; age between 58-74 years) with radiological lesions characteristic of Paget's disease, serum alkaline phosphatase (sALP) levels at least 50% above the normal range and never treated for their disease before, were given 200 IU/day of sCT nasal spray for 6 months. sALP levels were measured at month 3 and 6 of therapy; clinical data were recorded every month. sALP levels significantly dropped after 3 months of treatment (72 +/- 6% of basal level, p less than 0.01). After 6 months of therapy sALP levels were similar to the 3 month levels. Pain and functional impairment self-evaluated by the patients decreased after 6 months of therapy: pain index from 5.5 +/- 2.2 to 2.1 +/- 1.1, p less than 0.01; functional impairment index from 2.2 +/- 0.5 to 0.7 +/- 0.5, p less than 0.01. Side-effects were not observed during the entire period of the study. In conclusion, the 200 IU daily regimen of the i.n. spray of sCT without absorption enhancer was, for our patients, effective, safe, and well tolerated in the long-term therapy of Paget's disease.