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SUMMARY
Pieces of adrenal medulla, together with inner zone cortical cells, were inserted into the anterior chamber of the rabbit's eye in eighty-four instances. Care was taken to exclude the outer parts of the adrenal cortex. Both chromaffin and cortical cells were vascularized by the iris and persisted in the eye for many months in spite of the presence of the whole or part of the right adrenal gland. Partial removal of the right adrenal gland was followed by a proliferation of the cortical elements of the graft. ACTH injections (5 mg twice daily for 21 days) did not induce cellular proliferation. The findings indicate that adrenocortical cells will persist in a graft and proliferate in spite of the presence of abdominal adrenocortical tissue and that the inner zone cells of the rabbit's adrenal can be successfully grafted and are capable of proliferating in response to a partial removal of the remaining normal adrenal cortex.
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SUMMARY
The effects of corticosterone and deoxycorticosterone in concentrations of 10 and 30 μ./ml. on organ cultures of extra-adrenal chromaffin cells of neonatal rabbits were investigated.
The presence of corticosterone resulted in synthesis and storage of about 35% of adrenaline. Deoxycorticosterone did not induce methylation so that the ratio of catecholamines remained at about 90% noradrenaline.
The results indicate the importance of the 11-oxy group in steroid-induced methylation of catecholamines.
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Pieces of foetal rat pancreas obtained from specimens of 18–40 mm c.r. length were implanted into the anterior chamber of the mother's eye. The subsequent changes were followed using histological methods.
Acinar tissue degenerates and completely disappears during the first 2 weeks after implantation. Duct epithelium proliferates and large numbers of islets of Langerhans are produced which contain both α and β cells. In grafts of 1 year's duration islets form the main bulk of the graft. Methods of staining the islet tissue of the rat are discussed.
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A single intravenous injection of reserpine (15 mg/kg) into albino rats of the Wistar strain will produce a near complete depletion of adrenal medullary catechol amines within 24 hr. Following this change, pressor amines are resynthesized and stored by the chromaffin cells and reach normal levels after a period of 9–14 days. During the early part of this period noradrenaline is re-formed and stored more rapidly than adrenaline, and is present in greater than normal amounts in the regions of the medulla which are normally concerned with storing adrenaline. It is, therefore, possible that methylation of the primary amine may be a rate-limiting factor in adrenaline synthesis.
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Auto- and homografts of adrenal medullae depleted of reserpine were used in order to follow the rate of synthesis and storage of pressor amines in non-innervated chromaffin cells. The changes were followed by histochemical methods. The findings indicate that there is no significant difference between the rate of storage of catechol amines in the implanted chromaffin cell and in the normal adrenal medulla.
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The distribution of chromaffin tissue in the rabbit, frog and dogfish is described and compared with findings previously reported for the human foetus. The results are correlated with the adrenaline-noradrenaline content of the tissues.
It is shown that in the dogfish, where the chromaffin tissue is completely separate from adrenocortical material, the pressor activity of the tissue is entirely due to noradrenaline. In man and rabbit the intra-adrenal chromaffin tissue contains a mixture of adrenaline and noradrenaline, whilst the pressor activity of the extra-adrenal chromaffin tissue (para-aortic bodies) is entirely due to noradrenaline.
The para-aortic bodies of the human foetus are probably endocrine organs and may be concerned with the humoral control of vasomotor tone.
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SUMMARY
The adrenaline and noradrenaline content of the adrenal medulla and medullary implants has been assessed by histochemical and assay techniques after the injection of insulin, reserpine, and choline 2:6-xylylether bromide (TM10) into Wistar and Sprague-Dawley strain rats. Insulin hypoglycaemia is without effect on implanted chromaffin cells, but reduces the adrenaline content of the intact adrenal. Reserpine reduces the catechol amine content of both normal and grafted chromaffin cells. TM10, given as a single intravenous injection, has no effect on either normal or implanted chromaffin cells.
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SUMMARY
Sections of human skin obtained from a variety of sites and from subjects of different ages have been examined. Mast cells, melanocytes and melanophores have been identified by the use of various staining procedures, but the 'chromaffin cells' reported by Adams-Ray & Nordenstam (1956) and Burch & Phillips (1958) have not been observed. The staining reactions of pressor amine-containing chromaffin cells are reviewed and contrasted with those of the granular cells of the skin.
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SUMMARY
Polymorphic cells whose granules give a positive chromaffin reaction have been identified in the liver capsule and gut of the ox, cow and sheep. These cells give a positive argentaffin and Schmorl's reaction in dichromate-fixed material, and fail to couple with alkaline diazonium compounds. These reactions are consistent with the presence of a catechol, and from the work of Bertler, Falck, Hillarp, Rosengren & Torp (1959) it would appear that they contain dopamine.
These chromaffin, dopamine-containing cells are, however, not a special type of cell but are tissue mast cells. Nuclear fast red (Herzberg) is not, as suggested by Falck, Hillarp & Torp (1959a, b), a specific stain for dopamine, but, when prepared with aluminium sulphate, it is specific for sulphated mucopolysaccharides.
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The intracellular localization of l-[4,5-3H]leucine in chromaffin cells has been observed using light and electron microscopic autoradiography and the association of the labelled amino acid with particular cell components confirmed by statistical analysis. By making observations at short intervals after a single intravenous pulse of [3H]leucine it has been possible to follow the movement of the isotope from the endoplasmic reticulum through the Golgi complex to the chromaffin granules. No evidence for movement of the label through the Golgi complex was observed in adjacent cortical cells. The time sequence of transport of the amino acid through the various cell organelles was very similar to that observed by previous workers in protein-secreting exocrine cells.
