U. S. v. Euler

A specific kind of noradrenaline granules in the vesicular gland and the vas deferens of the bull

Abstract Noradrenaline containing granules from the vas deferens and the vesicular gland of the adult bull show a spontaneous NA release rate which is about 3 times lower than that in granules from bovine splenic nerves. The granules also differ from splenic nerve granules with regard to amine uptake and in response to various drugs. It is suggested that the appearance of a special kind of NA granules in the accessory male genital organs studied is related to the special function and to the occurrence of short adrenergic neurons characteristic of these organs.

CATECHOLAMINES AND NUCLEOTIDES IN PHAEOCHROMOCYTOMA.

Abstract Isolated catecholamine (CA) storage granules from a phaeochromocytoma were studied in vitro . The tumour granules had a high NA content, while A amounted to only a few per cent of the total CA. Most of the amines were particle bound. The storage granules had a lower density and adenine nucleotide content than bovine adrenal medullary granules. Thus only a minor part of the CA in this tumour could be stored by a mechanism requiring stoichiometric relationship between amines and adenine nucleotides. On incubation in vitro ATP was lost at a slightly higher rate than the CA, leading to an increase in the molar CA/ATP ratio. The ATP lost was quantitatively recovered as AMP in the extragranular medium. ATP-splitting activity occurred to some extent in the particle-free supernatant but was more evident in the high speed sediment. When the tumour was stored in a refrigerator at +2° a gradual loss of CA occurred while the ATP remained unchanged. Thus from the third day and onwards a CA/ATP ratio giving an equivalence ratio close to unity was established. On incubation of such granules the rate of CA loss was found to be slightly increased while that of ATP loss was unchanged. ATP or ADP and magnesium addition to the incubation medium partly prevented the spontaneous decrease of the storage granule CA. Phenoxybenzamine caused a profound fall in the CA and ATP content, while reserpine did not have any clearcut effects on the granules, in the concentrations used.

Uptake of catecholamines in the rabbit heart after depletion with decaborane

Abstract After 80–90 per cent depletion of the rabbit heart with decaborane, injection of noradrenaline (NA) causes an increase of the amine content to near normal values. The amines taken up show normal distribution between the high speed sediment and supernatant, indicating a dynamic equilibrium between the particulate and the supernatant fractions. The amines taken up leave the heart gradually in some 20 hours. When either the 1- or the d-isomer of adrenaline (A) is injected together with 1-NA, 2–3 times more of 1-A than of dA is taken up for the same amount of 1-NA. The two isomers appear to leave the stores at a similar rate.