EFFECTS OF PITUITARY HORMONES AND CORTICOSTERONE ON LIPOLYSIS IN HYPOPHYSECTOMIZED RATS

1974 ◽  
Vol 77 (3) ◽  
pp. 502-508 ◽  
Author(s):  
Ekkehard Schillinger ◽  
Erich Gerhards
Keyword(s):  
Growth Hormone ◽  
Adrenal Gland ◽  
Pituitary Gland ◽  
Hormonal Regulation ◽  
Pituitary Hormones ◽  
Fat Cells ◽  
Isolated Fat Cells ◽  
Hypophysectomized Rats ◽  
Pituitary Homogenate

ABSTRACT Removal of the pituitary gland in rats reduces basal lipolysis and greatly diminishes the lipolytic response of isolated fat cells towards L-epinephrine, ACTH and dibutyryl-cyclic-3′5′-AMP (DB-cAMP). Subcutaneous application for 5 days of ACTH, LH, FSH, GH and TSH, single or in combination, does not appreciably influence the responsiveness of fat cells towards lipolytic stimulation. Administration of a hypophyscal homogenate restores the sensitivity of fat cells of hypophysectomized rats. A similar effect is obtained with a combination of growth hormone and corticosterone. In hypophysectomized-adrenalectomized animals only the combination of growth hormone and corticosterone, but not a pituitary homogenate, produces a normal responsiveness of fat cells towards lipolytic stimuli. It is concluded that both the pituitary and adrenal gland are intimately involved in the hormonal regulation of lipolysis in fat cells.

Hormonal regulation of hepatic multidrug resistance-associated protein 2 (Abcc2) primarily involves the pattern of growth hormone secretion

2006 ◽  
Vol 290 (4) ◽  
pp. G595-G608 ◽  
Author(s):  
Francis R. Simon ◽  
Mieko Iwahashi ◽  
Ling-Jia Hu ◽  
Ishtiaq Qadri ◽  
Irwin M. Arias ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Multidrug Resistance ◽  
Hormonal Regulation ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Pituitary Hormones ◽  
Bile Canaliculus ◽  
Mrna Levels ◽  
Hypophysectomized Rats

Biliary excretion is the rate-limiting step in transfer of bilirubin, other organic anions, and xenobiotics across the liver. Multidrug resistance-associated protein 2 (Mrp2, Abcc2) is the major transporter for conjugated endo- and xenobiotic-conjugated compounds into bile. Hormones regulate bilirubin and xenobiotic secretion into bile, which have dimorphic differences. Therefore, we examined the possible role of sex steroids and growth hormone in the regulation of Mrp2. In ∼8-wk-old rats, mRNA, transcriptional activity, and hepatic content of Mrp2 were selectively increased fourfold ( P < 0.001) in females compared with males. In males, estrogens increased and testosterone decreased Mrp2 mRNA and protein, whereas no significant effect was measured in females, suggesting either a direct effect on the liver or an alteration in growth hormone secretory pattern. After hypophysectomy, Mrp2 mRNA was markedly reduced and the effects of estrogens and testosterone on Mrp2 were prevented, supporting the role of pituitary hormones in controlling Mrp2 expression. Mrp2 increased following growth hormone infusion in males. Mrp2 mRNA was decreased in growth hormone-deficient “Little” mice. Growth hormone infusions in hypophysectomized rats partially restored Mrp2 levels, whereas thyroxine addition returned Mrp2 mRNA and protein to basal levels. Morphology as well as biochemical measurements demonstrated that Mrp2 was localized to the bile canaliculus in equal density in both genders, whereas hormone replacements increased Mrp2 in hypophysectomized animals. In cultured hepatocytes, thyroxine did not have an effect, but growth hormone alone and combined with thyroxine increased Mrp2 mRNA levels. In conclusion, Mrp2 levels are regulated by the combination of thyroxine and different growth hormone secretory patterns.

IN VITRO AND IN VIVO EFFECT OF GROWTH HORMONE ON ALDOSTERONE SECRETION

1960 ◽  
Vol 38 (1) ◽  
pp. 1069-1075
Author(s):  
O. J. Lucis ◽  
E. H. Venning
Keyword(s):  
Growth Hormone ◽  
Adrenal Gland ◽  
Human Growth Hormone ◽  
Human Growth ◽  
Secretion Rate ◽  
Aldosterone Secretion ◽  
Hypophysectomized Rats

Porcine, monkey, and human growth hormone have no effect on the in vitro secretion of aldosterone by the rat adrenal gland. When monkey growth hormone is injected into hypophysectomized rats, the adrenals of these animals secrete, under in vitro conditions, increased amounts of aldosterone with no change in the secretion rate of corticosterone. The plasma of these rats contains a substance which appears to stimulate the secretion of aldosterone in the adrenals of normal rats.

LIPOLYSIS IN CHICKEN ADIPOSE TISSUE IN VITRO

1969 ◽  
Vol 43 (2) ◽  
pp. 285-294 ◽  
Author(s):  
D. R. LANGSLOW ◽  
C. N. HALES
Keyword(s):  
Growth Hormone ◽  
Adipose Tissue ◽  
Sodium Succinate ◽  
Fat Cells ◽  
Propranolol Hydrochloride ◽  
Isolated Fat Cells ◽  
Adipose Tissue In Vitro ◽  
High Concentrations ◽  
Long Acting

SUMMARY The effects on lipolysis of various compounds have been studied in intact chicken adipose tissue and in isolated fat cells prepared from chicken adipose tissue. Glucagon stimulated lipolysis at concentrations down to 1 ng./ml. in intact pieces and 0·1 ng./ml. in isolated fat cells. The effect was enhanced by high concentrations of insulin. No anti-lipolytic effect of insulin was observed. Adrenaline, noradrenaline, porcine corticotrophin (ACTH) and long-acting ACTH were lipolytic but the effects were small and high concentrations were required. The adrenaline effect was blocked by propranolol hydrochloride. Dibutyryl 3′,5′-(cyclic)-AMP and theophylline stimulated lipolysis as did a combination of crude chicken growth hormone and hydrocortisone sodium succinate. It was concluded that the pattern of response of chicken adipose tissue was markedly different from that of the rat.

Effect of chronic administration of insulin on pituitary gland content of growth hormone in the normal rat

1970 ◽  
Vol 48 (2) ◽  
pp. 85-89 ◽  
Author(s):  
Robert L. Hazelwood ◽  
John G. Galaznik
Keyword(s):  
Growth Hormone ◽  
Body Weight ◽  
Young Adult ◽  
Pituitary Gland ◽  
Chronic Administration ◽  
Female Rats ◽  
Pituitary Glands ◽  
Hypophysectomized Rats ◽  
Normal Rat ◽  
Gland Content

Acetone-dried pituitary glands from young adult female rats (starting weight 165–168 g) previously injected (s.c.) with doses of insulin of 0.5 U to 1.0 U/kg body weight for 4 days, and then with 2.0 U/kg 6 days a week for an additional 34 days, were bioassayed in young hypophysectomized rats for growth hormone content. Insulin-injected rats gained significantly more weight than saline-injected controls. The tibia cartilage width of the insulin-injected donor rats was greater than that of control rats after 9, 17, 24, and 31 days of insulin; pituitary gland preparations from these insulin-injected rats increased tibia cartilage widths slightly but significantly over those of rats injected with control pituitary gland preparations.

THE LIPID-MOBILIZING EFFECT OF SOME PITUITARY GLAND PREPARATIONS

1967 ◽  
Vol 56 (4) ◽  
pp. 626-648 ◽  
Author(s):  
Olav Trygstad
Keyword(s):  
Growth Hormone ◽  
Pituitary Gland ◽  
Serum Calcium Level ◽  
Human Growth ◽  
Pituitary Hormones ◽  
Unit Weight ◽  
Pituitary Hormone ◽  
Human Pituitary ◽  
Human Pituitary Gland ◽  
Gland Extract

ABSTRACT 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.

THE PREPARATION OF SHEEP GROWTH HORMONE

1963 ◽  
Vol 26 (2) ◽  
pp. 259-263 ◽  
Author(s):  
A. L. C. WALLACE ◽  
K. A. FERGUSON
Keyword(s):  
Growth Hormone ◽  
Anterior Pituitary ◽  
Deae Cellulose ◽  
Pituitary Hormones ◽  
Starch Gel Electrophoresis ◽  
Epiphysial Cartilage ◽  
Pituitary Glands ◽  
Hypophysectomized Rats ◽  
Starch Gel ◽  
Main Components

SUMMARY Growth hormone has been prepared from sheep pituitary glands by chromatography of a simple buffer extract on DEAE-cellulose. The preparation appears to be free of other anterior pituitary hormones but shows two main components when analysed by starch gel electrophoresis. These components appear similar to those present in standard preparations of ox growth hormone. Sheep growth hormone prepared by this method is not significantly less active than purified ox growth hormone when compared by the tibial-epiphysial cartilage response in hypophysectomized rats.

The Effect of Pituitary Gland Disorders on Glucose Metabolism: From Pathophysiology to Management

2020 ◽  
Vol 53 (01) ◽  
pp. 16-23
Author(s):  
Guy I. Sydney ◽  
Konstantinos Michalakis ◽  
Ilias P. Nikas ◽  
Eleftherios Spartalis ◽  
Stavroula A. Paschou
Keyword(s):  
Growth Hormone ◽  
Glucose Metabolism ◽  
Pituitary Gland ◽  
Management Strategies ◽  
Pituitary Hormones ◽  
Current Management ◽  
Lifestyle Management ◽  
Appropriate Treatment ◽  
Unfavorable Effect ◽  
Circulating Levels

AbstractThis review aims to explore, present, and discuss disorders of glucose metabolism implicated in pituitary gland diseases, the appropriate interventions, as well as the therapeutic challenges that may arise. Pituitary pathologies may dysregulate glucose homeostasis, as both the excess and deficiency of various pituitary hormones can affect glucose metabolism. Increased circulating levels of growth hormone, glucocorticoids or prolactin have been shown to mainly provoke hyperglycemic states, while hypopituitarism can be associated with both hyperglycemia and hypoglycemia. Addressing the primary cause of these disorders with the use of surgery, medical treatment or radiotherapy forms the cornerstone of current management strategies. Physicians should bear in mind that some such medications have an unfavorable effect on glucose metabolism too. When unsuccessful, or until the appropriate treatment of the underlying pituitary problem, the addition of established antidiabetic therapies might prove useful. Further studies aiming to discover more accurate and effective drug preparations in combination with optimal lifestyle management models will contribute to achieving a more successful glycemic control in these patients.

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