ACCUMULATION OF ALPRENOLOL IN SOME POLYPEPTIDE HORMONE PRODUCING CELLS AND IN MELANIN-CONTAINING TISSUES

1975 ◽  
Vol 79 (1) ◽  
pp. 202-208 ◽  
Author(s):  
Premysl Slanina ◽  
Hans Tjälve
Keyword(s):  
Characteristic Feature ◽  
Pituitary Gland ◽  
Distribution Pattern ◽  
Pancreatic Islets ◽  
Adrenergic Receptor ◽  
Endocrine Cells ◽  
Whole Body ◽  
Blocking Drug ◽  
High Accumulation ◽  
Receptor Blocking

ABSTRACT The distribution of the β-adrenergic-receptor blocking drug alprenolol labelled with 3H was studied in mice by whole body autoradiography. The most characteristic feature in the distribution pattern was the accumulation in endocrine cells within the pancreatic islets, the adrenal medulla, the pituitary gland and some cells of the thyroid, presumably representing the parafollicular cells. A high accumulation was also observed in melanin-containing tissues.

STUDIES ON THE TISSUE-DISPOSITION AND FATE OF [14C]STREPTOZOTOCIN WITH SPECIAL REFERENCE TO THE PANCREATIC ISLETS

1978 ◽  
Vol 89 (2) ◽  
pp. 339-351 ◽  
Author(s):  
Eva Britt Johansson ◽  
Hans Tjälve
Keyword(s):  
Pancreatic Islets ◽  
High Capacity ◽  
Whole Body ◽  
Side Chain ◽  
High Accumulation ◽  
Methyl Group ◽  
Whole Body Autoradiography ◽  
Selective Labelling ◽  
Chinese Hamsters ◽  
Tissue Disposition

ABSTRACT The tissue-disposition and fate of [14C]streptozotocin, labelled in the methyl-group of the N-nitrosomethylurea side-chain, have been studied in mice. Whole-body autoradiography, quantified by densitometric measurements, showed that the pancreatic islets had a high capacity to accumulate radioactivity after the injection of [14C]streptozotocin. Microautoradiography of the pancreas showed that centrally located cells were labelled while peripherally located cells contained a low labelling, indicating a selective labelling of the β-cells. A high radioactivity was present in the liver and the cortex of the kidney at most survival intervals. About 17 % of the radioactivity was exhaled as 14CO2 during 6 h, which shows that the methyl group of the N-nitrosomethylurea side-chain is split off. Radioactivity was shown to be incorporated in the acid-insoluble precipitate of the pancreatic islets, the liver, the kidney, and the exocrine pancreas. This may, to a varying extent, be due both to alkylating reactions and to incorporation of radioactivity in the macromolecules of the tissues via normal metabolic pathways. About 44 % of the radioactivity was excreted as unchanged [14C]streptozotocin in the urine during 24 h, while about 1 % of the radioactivity was found in the faeces. Whole-body autoradiography of [14C]streptozotocin in two Chinese hamsters and one rat also showed a high accumulation of radioactivity in the pancreatic islets in these species.

ACCUMULATION OF NICOTINE IN PANCREATIC ISLETS AND CALCITONIN-PRODUCING CELLS IN MICE AND CHICKS DEMONSTRATED BY MICRO- AND WHOLE-BODY AUTORADIOGRAPHY

1973 ◽  
Vol 58 (1) ◽  
pp. 21-NP ◽  
Author(s):  
PREMYSL SLANINA ◽  
HANS TJÄLVE
Keyword(s):  
Pancreatic Islets ◽  
Biogenic Amines ◽  
Whole Body ◽  
High Accumulation ◽  
Metabolic Studies ◽  
Whole Body Autoradiography ◽  
Parafollicular Cells ◽  
Ultimobranchial Glands ◽  
Endocrine Organs

SUMMARY By autoradiographic methods, nicotine was shown to be specifically accumulated in the pancreatic islets in mice. The results also indicated a high accumulation of nicotine in the parafollicular cells of the thyroid in mice and an accumulation was also shown in the ultimobranchial glands in chicks. Like the parafollicular cells of the thyroid in mammals, the ultimobranchial glands of birds are known to produce calcitonin. Metabolic studies with nicotine in vitro and autoradiographic studies with the main nicotine-metabolite cotinine, indicated an accumulation of unchanged nicotine (not metabolites) in the cells. The results are discussed in view of the fact that biogenic amines have been shown to be operative in these endocrine organs. It is suggested that nicotine can share common transport and/or storage mechanisms with biogenic amines in the cells. An effect of nicotine on hormone storage and/or release may take place via an interference with aminergic mechanisms in the cells.

The Influence of Adrenergic Receptor Blocking Agents on the Mouse Thyroid

1970 ◽  
Vol 39 (6) ◽  
pp. 781-791 ◽  
Author(s):  
Pat Kendall-Taylor ◽  
D. S. Munro
Keyword(s):  
Adrenergic Receptor ◽  
Adenosine Monophosphate ◽  
Thyroid Stimulating Hormone ◽  
Adrenergic Blockade ◽  
Blocking Drug ◽  
Receptor Blocking ◽  
Long Acting ◽  
Adrenergic Blocking ◽  
Mouse Thyroid

1. The influence of adrenergic receptor blocking drugs on the mouse thyroid gland maintained in vitro has been investigated. 2. Phentolamine, an α adrenergic blocking drug, and propranolol, a β blocking drug, inhibited the release of [131I]iodothyronines from pre-labelled mouse thyroids, which otherwise occurred when the glands were incubated in the presence of thyroid stimulating hormone, long acting thyroid stimulator, or cyclic 3′5′-adenosine monophosphate. 3. Evidence is presented to show that (a) the inhibition is not due to adrenergic blockade, (b) the effect cannot wholly be attributed to the prevention of adenyl cyclase activation, (c) the mechanism of action of the two drugs is dissimilar. 4. The observed clinical response in the treatment of thyrotoxicosis does not appear to be related to this antithyroid effect of propranolol.

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