Einfluß verschiedener Hormone auf die Bildung von Adenosin‐3′ : 5′‐monophosphat und Guanosin‐3′: 5′‐monophosphat durch partikuläre Präparationen aus der Rattenniere

Abstract

Hormonal influences on the formation of adenosine 3': 5'-monophosphate (Ado-3': 5I-P) have been studied in particulate preparations from rat kidney. Adenylate cyclase activity has been determined by measuring labeled Ado-3': 5'-P formed from labeled ATP (1 mM) in the presence of Mg++ (10 mM) and an ATP regenerating system.Hormonal effects on adenylate cyclase obtained from different parts ofthe kidney were found to correspond with the known tubular sites of action of these hormones in micropuncture studies. -Parathyroid hormone and thyrocalcitonin which are known to inhibit the reabsorption of inorganic phosphate in the proximal part of the renal tubule, increased the activity of adenylate cyclase obtained from renal cortex. The influence of these hormones on medullary adenylate cyclase activity was very small. Cortical adenylate cyclase activity was increased by parathyroid hormone in concentrations as low as 3 nM. A maximum 4.5-fold stimulation occurred with 10 pM parathyroid hormone. Over the same concentration range, thyrocalcitonin stimulated cortical adenylate cyclase. I n contrast to parathyroid hormone, maximal stimulation by thyrocalcitonin was only 2.5-fold. -The permeability for water of the distal convoluted tubules and the collecting ducts of the rat kidney is known to be increased by antidiuretic hormone. This hormone (Lysa-vasopressin) as well as oxytocin stimulated both cortical and medullary adenylate cyclase. The enzyme prepared from the medulla of rats with a hereditary hypothalamic diabetes insipidus (Bratteboro strain) was activated up to 4-fold by the addition of lysine vasopressin in concentrations between and 10-6 M. For comparable stimulation by oxytocin about 50 times higher concentrations were necessary than of lysine vasopressin. This finding corresponds to the lower antidiuretic potency of oxytocin compared to antidiuretic hormone. -By addition of neurohypophyseal hormones as well as of parathyroid hormone or thyrocalcitonin in very high concentrations, medullary and cortical adenylate cyclase activities were decreased compared to the activities measured in the presence of maximally effective hormone amounts. Trichlorisobutanol, which is used as a preservative in hormone preparations, caused no decrease in enzyme activity. -When antidiuretic hormone was added a t a maximally effective concentration to a cortical adenylate cyclase preparation in combination with parathyroid hormone or thyrocalcitonin a t nearly maximally effective concentrations, the effects of the hormones were essentially additive.Prostaglandin E, known to influence the permeability for water in the urinary bladder of the toad and in collecting ducts from mammalian kidneys, had no significant effect on medullary adenylate cyclase activity when added in concentrations between 3 -10-lo and 3 * lop6 M.Prostaglandin El was also without effect in the presence of lysine vasopressin (25 nM). Neither isoproterenol nor noradrenaline (50 pM) altered medullary adenylate cyclase activity although adrenergic stimulating agents h...

Cellular Action of Antidiuretic Hormone in Mice with Inherited Vasopressin-Resistant Urinary Concentrating Defects

“…1, the urine osmolalities in each of the four experiments on each genotype (Table I) have been plotted as a function of the maximal AVP-stimulated activity of adenylate cyclase. There is a highly signifi-'The data supporting this assertion are contained in a thesis, and it is not clear from the published report (34) whether the increase in en-.yme activity refers to absolute values or to a proportional increase over basal activity.…”

“…Schultz, Jaboks, Bdhme, and Schultz (34) measured the activity of renal medullary adenylate cyclase in rats with hypothalamic diabetes insipidus (Brattleboro strain), which are in a state of chronic water diuresis that can be corrected by vasopressin (35). Although they found lower basal activity of adenylate cyclase in these rats, the stimulation by vasopressin was greater, not less, than in control animals (34). 4 In rats with polyuria induced by potassium depletion, Pawlson, Taylor, Mintz, Field and Davis (33) found an increase rather than a decrease in the renal medullary concentration of cyclic AMP in response to vasopressin.…”

Hormonal Control of Renal Phosphoenolpyruvate Carboxykinase Activity during Development of the Rat

“…However, as with glucagon, cAMP has no effect on kidney PEP carboxykinase activity. Glucagon does not stimulate cAMP production in kidney but parathyroid hormone, thyrocalcitonin and some catecholamines, such as norepinephrine and isopretenol do [19,27]. Clearly, these hormones are unlikely to influence renal PEP carboxykinase activity.…”

Metabolism of Isolated Kidney Tubules Independent Actions of Catecholamines on Renal Cyclic Adenosine 3′: 5′‐Monophosphate Levels and Gluconeogenesis

“…Gua-3':5'-P has been discussed as second messenger of the a-adrenergic action by Goldberg [29] and by Gill and Casper [21]. Although Gua-3':5'-P has been found to be formed and secreted by the kidney in vivo and in vitro [8,30,31], and cr-adrenergic stimulation in vivo increased Gua-3':5'-P excretion [32], the experimental evidence for the role of this cyclic nucleotide in adrenergic actions in the kidney is sparse.…”