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Y Munari

Publications and source records attributed to Y Munari.

5 recordsLinked to original sources
PubMed1977

Thyroxine secretion by isolated hog thyroid cells: a cyclic AMP independent pathway.

The release of 131I-labeled thyroxine (T4) from isolated hog thyroid cells was increased 1.5--2-fold by thyrotropin (TSH). Dibutyryl cyclic AMP failed to reproduce this TSH action. In this in vitro system another cell activity, T4 synthesis, was stimulated in an essentially identical fashion by TSH and dibutyryl cyclic AMP (time course of action, dose-response relationship). 3-Isobutyl-1-methylxanthine (IBMX), 0.5 mM, did not alter the basal [131I]T4 release whereas it enhanced the [131I]T4 synthesis. TSH, 60 MU/ml, increased the intracellular cyclic AMP concentration 3-4-fold. Chlorpromazine (5 X 10(-4)M) abolished the TSH stimulation of cyclic AMP accumulation but did not alter the TSH-induced increase in [131I]T4 secretion. It is concluded that the TSH action on [131I]T4 secretion by isolated thyroid cells is not mediated by the adenylate cyclase-cylic AMP system.

Animals↗
PubMedDate not supplied

[Proceedings: Iodine metabolism in isolated human thyroid cells (hyperplastic goitre and toxic adenoma) (author's transl)].

We present here data on hormone synthesis and thyroxine secretion by isolated human thyroid cells. Thyroid cells were dispersed by trypsinization. Thyroid tissue was surgically obtained from two euthyroid patients with hyperplastic goitre and from two thyrotoxic patients with toxic adenoma. In 6 hr incubation experiments, we observed that isolated human thyroid cells, i) concentrated iodide, ii) synthetized iodothyronines, iii) released thyroxine in the incubation medium. Each parameters was TSH dependant. That thyroxine release was due to a secretion process is suggested by similar and further documented data obtained with isolated hog thyroid cells. This technique may provide further help for thyroid physiopathology investigation in humans.

Adenoma↗
PubMedDate not supplied

[Multiple effects of resorcinol on thyroid function (author's transl)].

In rats, I.V. injected resorcinol led to a decrease in thyroid radioiodine uptake and labelled iodothyronine/iodotyrosine ratio with no changes in the percent of thyroidal labelled iodide or radioiodine release. When thyroid lobes were incubated in vitro with radioiodine, resorcinol concentrations from 10(-3)M to 10(-6)M gave an increase in the percent of thyroidal labelled iodide and iodotyrosine/iodothyronine ratio. In animals fed 5% resorcinol for 2 weeks we observed an increase in thyroid weight, a decrease in plasma T4, no change in the percent of free T4, a decrease in T4 half life and no significant changes in T3 half life. Thyroidal labelled MIT/DIT and T3/T4 atios increased. Resorcinol, given in diet during 5 days to rats which had a low thyroidal thyroglobulin content after PTU administration for 2 weeks, gave, in comparison with rats fed PTU only, an increase in thyroidal thyroglobulin/DNA ratio and a decrease in thyroidal radioiodine release contrasting with an increase in plasma TSH. These differences did not exist when resorcinol was given for one month.

Administration, Oral↗