Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rabbits were anesthetized with urethane, and the concentration of 3',5' cyclic adenosine monophosphate (cAMP) in cerebrospinal fluid (CSF) was measured before and after injection into the cisterna magna of the following biologically active peptides and amines; adrenocorticotropin (ACTH), beta-melanocyte-stimulating hormone (beta-MSH), choroid plexus peptide IIF, arginine vasopressin, oxytocin, glucagon, epinephrine, serotonin, histamine, and acetylcholine. Only epinephrine and the lipolytic-melanotropic peptides ACTH, beta-MSH, and IIF influenced cAMP. Five to 500 mug ACTH caused a 3 to 10X increase in cAMP within 30 min; the concentration of nucleotide returned to baseline within 60-90 min after 5 or 50 mug, and remained elevated for at least 120 min after 500 mug. Effects of the same magnitude and tempo as those caused by 5 to 500 mug ACTH were produced by .1 to 10 mug beta-MSH and 5 to 500 mug IIF. Epinephrine at doses of 5 to 500 mug caused rises in cAMP of similar degree as the same dose of ACTH or peptide IIF, but the peak value was not reached until 60 to 90 min after injection.
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PMID:Effect of intrathecal injection of melanotropic-lipolytic peptides on the concentration of 3',5' cyclic adenosine monophosphate in cerebrospinal fluid. 17 24

The established cell lines isolated from mammalian kidney were characterized by its receptor activities against hormones and the ability to synthesize sulfolipids localized in the renal tubule. The level of 3':5'-cyclic AMP in JTC-12.P3 (monkey kidney) cells increased in 2 min as much as 2.5-5-fold on activation with 1.0 unit/ml of bovine parathyroid hormone or 1.9 units/ml of synthetic parathyroid hormone (1-34) resulting in intracellular cyclic AMP concentration of more than 40 pmol/mg protein. Prostaglandin E1 (14 micronM) and isopropylnorepinephrine (10 micronM) were also found to increase the concentration of cyclic AMP by more than 30- and 9-fold, respectively. Addition in medium of calcitonin, arginine vasopressin, adrenocorticotropic hormone and glucagon caused no significant changes of cyclic AMP level in the cell. In contrast, MDCK, a cell line isolated from canine kidney, reacted to arginine vasopressin, isopropylnorepinephrine and prostaglandin E1 and only slightly to parathyroid hormone. MDBK cell line derived from bovine kidney or fibroblast cell lines from rat lung and guinea pig kidney did not react to any of the hormones specific to kidney, i.e. arginine vasopressin, calcitonin or parathyroid hormone in the presence of theophylline. However, in the presence of 2 mM isobutylmethylxanthine, small but significant elevation of cellular cyclic AMP levels in response to calcitonin, arginine vasopressin, isopropylnorepinephrine and prostaglandin E1 was observed. The cell lines JTC-12, MDCK and MDBK, when incubated with H235SO4, incorporated the isotope into sulfolipids assigned as sulfatides and ceramide dihexoside sulfate or in MDCK also into cholesterol sulfate. The results suggested that JTC-12, MDCK and MDBK cell lines are epithelial origin and also JTC-12 and MDCK originated most probably from renal tubular cells of cortex and medulla, respectively.
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PMID:Hormone-specific responses and biosynthesis of sulfolipids in cell lines derived from mammalian kidney. 20 43

Recent studies have suggested a selective effect of atrial natriuretic peptide (ANP) in regulating NaCl reabsorption in juxtamedullary nephrons. We examined (a) functional differences between medullary thick ascending limbs from long and short loops of Henle (lMAL and sMAL, respectively) and (b) the interaction of ANP and arginine vasopressin (AVP) on Cl- transport (JCl) in these two segments. AVP-, glucagon-, and calcitonin-stimulated cAMP accumulation was higher in lMAL than in sMAL. 10(-10) M AVP increased JCl in lMAL but not in sMAL. ANP-stimulated cGMP production was higher in lMAL than in sMAL. 10(-10) and 10(-8) M ANP inhibited AVP-stimulated JCl in lMAL by 26-30% (from 70.3 +/- 11.4 to 51.7 +/- 13.6 pmol/mm per min and from 88.1 +/- 10.1 to 61.8 +/- 11.7 pmol/mm per min, respectively), and this effect was mimicked by 10(-5) to 10(-4) M cGMP. This effect of ANP in lMAL could account for a large part of the ANP-induced natriuresis and diuresis in vivo, in that the rate of NaCl reabsorption in MAL is the largest among distal nephron segments, providing the chemical potential energy for the renal countercurrent multiplication system.
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PMID:Effects of atrial natriuretic peptide and vasopressin on chloride transport in long- and short-looped medullary thick ascending limbs. 132 36

Identification of hormone target sites in the nephron has been achieved in part using autoradiography, and largely with microdissection and microanalysis techniques that permit quantitative measurements of hormone binding or postbinding effects in discrete nephron segments. The nephron target sites of hormones whose intracellular second messenger is known have been located by measuring their stimulatory effect on cyclic AMP or GMP production along the nephron. These hormones include arginine vasopressin, parathyroid hormone, calcitonin, and beta-adrenergic catecholamines. In contrast, the action sites of hormones whose cellular mediators are less well understood have been identified using micro modifications of conventional binding techniques scaled down to the minute (less than or equal to 1 microgram protein) amount of tissue available. In this group are aldosterone, corticosterone, insulin, angiotensin II, alpha-adrenergic catecholamines and dopamine. Atrial natriuretic peptides and glucagon have been studied with both methods. The precise localization of hormone receptors and sites of action in the functionally heterogeneous nephron is critical for understanding the interactions between the kidney and the endocrine system in fluid volume homeostasis, blood pressure control, and in biochemical and metabolic regulation.
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PMID:Hormone receptors and sites of action in the kidney. 132 67

The inner medullary collecting duct (IMCD) of the rat consists of two structurally and functionally distinct segments, i.e., the initial and the terminal IMCD. To identify factors that may regulate the transport function in the IMCD segments, we assessed whether catecholamines, carbachol, prostaglandin E2 (PGE2), bradykinin, glucagon, calcitonin, parathyroid hormone, or epidermal growth factor affects adenosine 3',5'-cyclic monophosphate (cAMP) production in microdissected tubules in the presence and absence of arginine vasopressin (AVP, 0.1 nM). All experiments were performed in the presence of 3-isobutyl-1-methylxanthine, and cAMP was measured by radioimmunoassay. Epinephrine (greater than or equal to 50 nM) and clonidine (greater than or equal to 1 microM) markedly decreased AVP-induced cAMP levels in both IMCD segments. However, phenylephrine did not show an effect. The inhibitory effect of epinephrine was blocked by yohimbine (50 nM) but not by prazosin (50 nM). In isolated perfused terminal IMCDs, epinephrine inhibited AVP-stimulated urea permeability. Isoproterenol (1 microM), in the absence of AVP, caused a significant increase in cAMP level only in the initial IMCD. Propranolol (1 microM) inhibited this isoproterenol effect, but atenolol did not. Dopamine (less than or equal to 1 microM) had no effect on cAMP levels in either IMCD segment. Carbachol, PGE2, and the various peptide hormones had no effect on cAMP levels (+/- AVP) in either IMCD segment. We conclude that an adrenergic beta 2-receptor is present only in the initial IMCD, where its occupation increases cAMP production. We conclude also that an adrenergic alpha 2-receptor is present in both IMCD segments, where its occupation inhibits AVP-induced cAMP production.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hormone and autacoid regulation of cAMP production in rat IMCD subsegments. 135 41

The acute effects of i.v. somatostatin (250 mcg bolus followed by 250 mcg/h continuous infusion for two hours) on renal hemodynamics, renal electrolyte and water handling, and urinary excretion of catecholamines and prostaglandins, as well as on plasma concentrations of arginine vasopressin, atrial natriuretic factor, norepinephrine, epinephrine, dopamine, glucagon, and plasma renin activity were studied in seven normal subjects. Somatostatin decreased effective renal plasma flow and glomerular filtration rate, osmotic and free water clearances, urine volume, and sodium and potassium excretion, while urinary osmolality, fractional excretion of sodium, and phosphate excretion increased significantly. Plasma concentrations of arginine vasopressin, atrial natriuretic factor, norepinephrine, epinephrine, and dopamine remained unchanged, while plasma renin activity (3.0 +/- 0.25 vs 2.4 +/- 0.2 ng AngI/ml/h; p less than 0.01) and glucagon levels (40 +/- 11 vs 20 +/- 16 pg/ml; p less than 0.01) decreased. Urinary excretion of norepinephrine, epinephrine, dopamine, PGE2, and PGF2 alpha was suppressed under somatostatin. A significant positive correlation was found between urinary dopamine and sodium excretion (r = 0.7; p less than 0.001) and urinary prostaglandin E2 and glomerular filtration (r = 0.52; p less than 0.01). Without accompanying changes in plasma osmolality and vasopressin concentration significant antidiuresis occurred, suggesting a direct tubular effect of somatostatin. However, the hormone-induced changes are due mainly to the decrease in renal plasma flow. The results demonstrate that somatostatin at supraphysiological doses exerts significant effects on the kidney.
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PMID:Effect of somatostatin on kidney function and vasoactive hormone systems in health subjects. 168 Nov 32

We investigated the tubular action of endothelin in rat nephron segments. The effects of endothelin on arginine vasopressin (AVP)-, parathyroid hormone-, glucagon-, calcitonin-, and isoproterenol-dependent cAMP accumulation were studied. The following nephron segments were microdissected: glomerulus (Gl), proximal convoluted tubule (PCT), cortical and medullary thick ascending limbs of Henle's loop (cTAL and mTAL, respectively), cortical collecting duct (CCD), outer medullary collecting duct (OMCD), and inner medullary collecting duct (IMCD). Endothelin dose dependently (10(-8)-10(-10)M) inhibited AVP-dependent cAMP accumulation in CCD, OMCD, and IMCD. This effect was independent of the presence or absence of phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, Ca channel blocker nicardipine, or indomethacin, but was abolished in the presence of protein kinase C inhibitor H-7. Protein kinase C stimulator dioctanoyl glycerol mimicked the effect of endothelin. On the other hand, endothelin had no inhibitory effect on AVP-dependent cAMP accumulation in cTAL or mTAL, parathyroid hormone-dependent cAMP accumulation in Gl and PCT, or glucagon-, calcitonin-, and isoprotereol-dependent cAMP accumulation in OMCD. We conclude that endothelin specifically inhibits AVP-dependent cAMP accumulation in CCD, OMCD, and IMCD through activating protein kinase C. This effect possibly has a role in maintaining urine volume to counteract the decrease in GFR caused by endothelin itself.
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PMID:Effects of endothelin on peptide-dependent cyclic adenosine monophosphate accumulation along the nephron segments of the rat. 169 79

The effect of two different regimens of intravenous infusion of amino acids on glomerular filtration rate (GFR), renal plasma flow (RPF), tubular sodium and water handling judged from the clearance of lithium (CLi), and plasma concentrations of angiotensin II (Ang II), aldosterone (Aldo), arginine vasopressin (AVP), atrial natriuretic peptide (ANP), growth hormone (GH), and glucagon was investigated in healthy humans. In the first protocol (n = 11) the infusion lasted 90 min; both GFR and RPF increased significantly (median increase 7.1% and 9.1% respectively, P less than 0.05 both). In the second protocol (n = 13) the infusion lasted 30 min; both GFR and RPF tended to increase (median increase 3.5% and 7.4%) but the change did not reach significance. The changes in tubular sodium and water handling were similar in the two protocols. Absolute reabsorption rates in the proximal tubules were unaltered, resulting in an increased output into the distal tubules that was totally compensated for by an increased distal reabsorption. Thus no changes in urinary excretion of sodium and water were observed. Ang II, Aldo, AVP, ANP and GH were unchanged by amino acid infusion, but glucagon increased. It is suggested that the alterations in renal haemodynamics and distal tubular reabsorption may be mediated by glucagon.
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PMID:Effect of two regimens of intravenous amino acid infusion on renal haemodynamics, renal tubular function and sodium and water homeostatic hormones in healthy humans. 187 82

The intestinal vascular responsiveness to arginine vasopressin was evaluated in rats with chronic portal hypertension. Male Sprague-Dawley rats were made portal hypertensive by stenosis of the portal vein. Ten to twelve days after the induction of chronic portal hypertension, the responsiveness of the small intestinal circulation to cumulative doses of vasopressin was evaluated using an isolated pump-perfused small intestinal preparation. The ED50 for maximal vasoconstriction was increased twofold in portal hypertensive rats compared with control rats. To determine if the impaired responsiveness to arginine vasopressin was related to the hyperglucagonemia of chronic portal hypertension, plasma glucagon levels were elevated in normal rats to levels previously measured in portal hypertensive rats (i.e. approximately 450 pg/mL), and the dose response studies were repeated. Glucagon significantly attenuated the responsiveness of the intestinal vasculature to vasopressin. Equipotent doses of nitroprusside also attenuated intestinal vascular responsiveness to vasopressin. The results indicate that there is a reduced vascular sensitivity to vasopressin in the intestine of portal hypertensive animals and suggest that elevations in circulating vasodilators in portal hypertensive conditions may partially explain this altered vascular responsiveness.
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PMID:Intestinal vascular sensitivity to vasopressin in portal hypertensive rats. 200 29

Recent results have demonstrated altered corticotropin-releasing factor (CRF)-41 content of the neurointermediate lobe (NIL) of the pituitary gland in response to various manipulations including osmotic stimulation. This study was undertaken to determine whether changes in CRF-41 content of the NIL are accompanied by changes in intensity of CRF-41-like immunoreactivity (CRF-41-LI) of neurosecretory neurones of the hypothalamus in response to osmotic stimulation. Wistar rats of both sexes given either tap water ad libitum, 2% NaCl solution, or access to tap water was limited to 20 min daily, for 7 days. Subsets of rats from each group were adrenalectomized (ADX) or treated with dexamethasone (DEX). Thirty-six hour before perfusion with fixative consisting of buffered formaldehyde and picric acid, animals received 75 micrograms colchicine i.c.v. Forty micrometer thick vibratome sections were stained for CRF-LI, arginine vasopressin (AVP-LI) and oxytocin (OXY-LI) using the avidin-biotin-peroxidase complex method. In response to both types of osmotic stimulation magnocellular neurones of the paraventricular (PVN) and supraoptic nuclei (SON) showed increased CRF-LI, AVP-LI and OXY-LI, while CRF-LI of parvocellular perikarya of the PVN decreased. The enhanced CRF-LI seemed to appear in a subset of magnocellular neurones with OXY-LI but not AVP-LI. Increased staining intensities were also observed in magnocellular neurones in ADX rats challenged osmotically. In contrast, systemic DEX administration, as well as implantation of DEX in the area on the SON, sharply attenuated CRF-LI but not AVP-LI or OXY-LI of magnocellular neurones in osmotically stimulated rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Oxytocinergic neurons in rat hypothalamus. Dexamethasone-reversible increase in their corticotropin-releasing factor-41-like immunoreactivity in response to osmotic stimulation. 211 29


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