Lipid-mobilizing effect has been observed for nearly all the accepted pituitary hormones and for several suggested pituitary 'lipotrophins'. Pituitary hormone preparations are usually not homogeneous, and even a highly purified ACTH (p.ACTH) contains less than 30 per cent pure adrenocorticotrophin.
Crude ACTH (c.ACTH) was found to be 250 times more adipokinetic in rabbits than p.ACTH, indicating that this effect was mainly due to impurities.
A lipid-mobilizing fraction (LMFr) was precipitated from a human pituitary gland extract before the preparation of growth hormone and crude gonadotrophins, whereby the adipokinetic effect of these preparations in the rabbit became negligible. Removal of LMFr gave an electrophoretically purified growth hormone with reduced molecular weight and an increased somatotrophic potency per unit weight in a radioimmunoassay system.
Injection of the lipotrophic preparations into rabbits lowered the serum calcium level, and concentrations below 3 meq./l were observed, often accompanied by convulsions and in some instances by death.
It is concluded that the adipokinetic and hypocalcaemic effects of c.ACTH, p.ACTH and the employed human growth hormone preparations in rabbits may be due to contaminations. It is suggested that the LMFr contains a human pituitary lipotrophic factor which may also be responsible for the hypocalcaemia observed in the rabbit.
EJE is committed to supporting researchers in demonstrating the impact of their articles published in the journal.
The two types of article metrics we measure are (i) more traditional full-text views and pdf downloads, and (ii) Altmetric data, which shows the wider impact of articles in a range of non-traditional sources, such as social media.
More information is on the Reasons to publish page.
Sept 2018 onwards | Past Year | Past 30 Days | |
---|---|---|---|
Full Text Views | 0 | 0 | 0 |
PDF Downloads | 0 | 0 | 0 |