Effects of noradrenaline and adrenaline on the thyroid

Abstract

When Labbe, Tinel & Doumer (1922) first described a patient with a phaeochromocytoma they noticed swelling of the root of the neck in the attacks of sweating, pallor and hypertension. Strombeck & Hedberg (1939) described swelling of the thyroid as at least part of the cause of this increase in neck size.It has been shown that phaeochromocytomata, in different patients, secrete varying proportions of noradrenaline and adrenaline (von Euler, 1951), and Barnett, Blacket, Depoorter, Sanderson & Wilson (1950) have described swelling of the region of the thyroid in two subjects given infusions of noradrenaline. We have carried out a number of experiments in both man and dogs to study this finding further, with particular reference to the changes in blood flow which occur. A preliminary report of these findings has appeared previously (Mowbray & Peart, 1958). METHODSMan Infusions of noradrenaline and adrenaline were given to fifty-one healthy young adults; forty-nine male and two female. All subjects were at rest on normal diet and infusions were given from 30 to 90 min after their midday meal.Infusions containing 4 pg/ml. of either noradrenaline or adrenaline in 0-9 % saline were given into an antecubital vein. The infusions were for periods of 30-90 min, and the infusion rate was adjusted so that the systolic blood pressure for most individuals lay between 170 and 190 mm Hg. The dose of both substances required to maintain this lay between 15 and 30 ug/min.Measurements of blood pressure were made by sphygmomanometer. The measurements of thyroid blood flow were made with a modification of Hensel's heated thermocouple needle (Mowbray, 1959). In this procedure a heated thermocouple is cooled by the tissue blood flow and a reference thermocouple in the same needle compensates for changes in tissue temperature. It was possible to contain the thermocouples and heater in a No. 12 hypodermic needle, which was small enough to be inserted almost painlessly in the thyroid through a small bleb of intradermal procaine solution. Readings of thyroid blood flow were made at 2 min intervals in most subjects, although direct recording of the blood flow has also been used. For this purpose a mirror galvanometer was used for taking spot readings and a DC amplifier with a direct-writing milliammeter for the continuous recordings.

Efferent Neuroendocrine Pathways of Sympathetic Superior Cervical Ganglia

“…Therefore, the present results differed in part from our previous obser vations in chronically SCGx rats in which the impending increase in thyroid response to TSH 7 days after surgery could be explained satisfactorily by an exclusive, intrathyroidal effect of denervation [42], There is no general consensus about the sort of influence that catecholamines exert on thyroid cells. Acute intraven ous injections of epinephrine or NE to dogs [38] or sheep [18] affected thyroid blood flow without changing the la beled hormone secretion. In rabbits, a continous infusion of epinephrine caused thyroid vasocontriction as well as a de pression of radioiodine uptake [7], A similar decrease in 1311 uptake was found in rats after epinephrine administration [5].…”

Central nervous system mediated stimulation by thyrotropin-releasing hormone of microcirculation in thyroid gland of rats.

“…This finding led us to consider that TRH in the CNS is capable of modifying the activity of the specific autonomic nerve efferents. On the other hand, the effects of epinephrine upon the thyroid have been extensively studied and shown to diminish thyroid blood flow (Ackerman and Arons, 1958;Mowbray and Peart, 1960;Falconer, 1967;Ahn et al, 1969). Contrary, acetylcholine is known to enhance thyroid blood flow (Soderberg 1958(Soderberg , 1959.…”

Evidence of intrathyroidal accumulation of TSH receptor antibody in Graves' disease

“…The thyroid, therefore, may be under constant stimulation. The increase in the TR-ab level due to adrenalin administration was probably due to adrenalin-induced constriction of the capillaries in the thyroid tissues (11), resulting in a voluminous flow of the TR-ab retained in the thyroid into the vein (10). However, some of our patients showed no increase in the TR-ab level, which may be due to the following factors: (a) The adrenalin concentrations used in the present study may not have been sufficiently high for adequate constriction of the capillaries in the thyroid tissues, (b) There may have been technical problems in the cannulation of the superior thyroid artery and the intra-arterial injection of adrenalin, for example, the tip of the cannula may have ruptured the arterial wall during the injection of adrena¬ lin, (c) The interval between adrenalin injection and blood sampling may have been inappropriate, (d) TR-ab in the non-responsive patients might not be produced in the thyroid gland.…”