Hyperglycaemia adrenaline

Reserpine, Chlorpromazine and other Psycholeptic Drugs Reserpine depletes postganglionic sympathetic fibres of their noradrenaline and the peripheral sympathetic responses of animals which have been pretreated with reserpine are those which would be expected to follow loss of sympathetic transmitter . Thus, in adrenalectomized, reserpinized cats, stimulation of the splanchnic nerves does not produce the increase in blood pressure which is seen in non-reserpinized animals. Hexamethonium normally produces hypotension due to ganglionic blockade in the reserpinized animal it is without effect. Reserpine also causes a loss of adrenaline from the adrenal medulla. Since this adrenaline is liberated into the blood stream, it is not surprising that reserpine causes hyperglycaemia. 

Small doses of adrenaline, inactive in control animals, have also been reported to protect adrenalectomized rats from the severe shock produced by egg-white [120, 244]. In fact, it has been suggested that the adrenal medulla, and not the adrenal cortex, protects rats from a fatal anaphylactoid response [392, 606]. Moreover, both adrenaline and noradrenaline inhibit the anaphylactoid reaction produced by egg-white [94, 119, 231, 248, 489] or dextran [125, 250] in the intact animal. Noradrenaline (a more potent vasoconstrictor than adrenaline) was always less active in these studies so that inhibition is probably not related to vasoconstriction (a classical alpha adrenergic action on the Ahlquist classification of adrenergic receptors [19]). Protection may involve an effect on carbohydrate metabolism as adrenaline is more potent than noradrenaline in producing hyperglycaemia [75, 356]. Moreover, the inhibitory effect of adrenaline on the anaphylactoid reaction [445] and its hyperglycaemic activity [116, 604] are inhibited by beta, but not by alpha, adrenergic blockade. 

Trendelenburg, U., Thyroid and hyperglycaemia produced by adrenaline and noradrenaline, Brit. J. Pharmacol. 8, 454 (1953). 

Adrenaline Tyrosine derivative Adrenal medulla Most cells Numerous vascular effects. Increased glycolysis and lipolysis. Hyperglycaemia... 

Hyperglycaemia is found in diabetes mellitus when insufficient insulin is present. This may be a primary condition or secondary to other conditions, e.g. when insulin antagonists are present in excess as in Cushing s disease (due to excess glucocorticoids), acromegaly (due to excess growth hormone) or phaeochromocytoma (due to excess adrenaline). 

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