Effects of a synthetic rat adrenomedullin on regional hemodynamics in rats

He, Hongbin; Bessho, Hideki; Fujisawa, Yoshihide; Horiuchi, Kensuke; Tomohiro, Atsufumi; Kita, Tomoyuki; Aki, Yasuharu; Kimura, Shoji; Takahashi, Toshiaki; Abe, Youichi

doi:10.1016/0014-2999(94)00683-x

Cited by 84 publications

(45 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This finding was compatible with the previous report that AM and CGRP exerted a potent vasodilator action via cAMP (7). Although HR was increased by both peptides, implying that reflexive sympathetic activation occurs as a result of both treatments, CI was increased by AM (23,24) but not by CGRP (15,16), in agreement with previous reports. This finding was probably due to the difference in cardiac-afterload reduction between the AM and CGRP groups.…”

Section: Discussionsupporting

confidence: 92%

Regional Hemodynamic Effects of Adrenomedullin in Wistar Rats: A Comparison with Calcitonin Gene-Related Peptide.

et al. 2002

View full text Add to dashboard Cite

Section: Discussionsupporting

confidence: 92%

Regional Hemodynamic Effects of Adrenomedullin in Wistar Rats: A Comparison with Calcitonin Gene-Related Peptide.

et al. 2002

View full text Add to dashboard Cite

“…also reported that AM2/IMD was found in heart. AM has been detected in the heart (3,25) and has a direct action on the heart (10,22). Thus AM2/IMD, as well as AM, may exert a direct positive inotropic effect.…”

Section: Discussionmentioning

confidence: 96%

“…AM is a multifunctional peptide that exhibits various actions, such as cardiovascular, renal, and respiratory regulation, as well as central nervous system regulation and regulation of other hormone secretions (2,10,12,16,21,28). AM has also been implicated in various disease states, such as heart failure and renal dysfunction (1,7,9,14,17,18,20).…”

mentioning

confidence: 99%

Roles of adrenomedullin 2 in regulating the cardiovascular and sympathetic nervous systems in conscious rats

Fujisawa¹,

Nagai²,

Miyatake³

et al. 2006

American Journal of Physiology-Heart and Circulatory Physiology

Self Cite

View full text Add to dashboard Cite

. Roles of adrenomedullin 2 in regulating the cardiovascular and sympathetic nervous systems in conscious rats. Am J Physiol Heart Circ Physiol 290: H1120 -H1127, 2006. First published October 14, 2005; doi:10.1152/ajpheart.00461.2005.-Recently, a new member of the calcitonin gene-related peptide (CGRP) family, adrenomedullin 2 (AM2) or intermedin (IMD), was identified. AM2/ IMD has been shown to have a vasodilator effect in mice and rats and an effect on urine formation in rats. In the present study, we investigated the effects of intravenously infused rat AM2 (rAM2) on blood pressure (BP), heart rate (HR), renal sympathetic nerve activity (RSNA), and renal blood flow (RBF) in conscious unrestrained rats relative to the effects of rat adrenomedullin (rAM) and proadrenomedullin NH 2-terminal 20 peptide (rPAMP). Intravenous infusion of rAM2 (5 nmol/kg) significantly decreased BP and increased HR, RSNA, and RBF. These hypotensive and sympathoexcitatory effects diminished after 20 min, and HR returned to control levels 30 min after cessation of the infusion. In contrast, a significant increase in RBF was still evident 60 min after cessation of the peptide infusion. The duration of BP, HR, and RSNA responses was longer with rAM (5 nmol/kg) than with rAM2 infusion, whereas the increases in RBF induced by rAM2 and rAM were similar in their amplitude and duration. Infusion of rPAMP (200 nmol/kg) increased HR and RSNA but had no effect on RBF. Baroreceptor denervation suppressed, but did not diminish, the increases in HR and RSNA to rAM2. These findings indicate that the physiological roles of rAM2 and rAM are similar and that rAM2 also has a long-lasting vasodilator action on the renal vascular bed.hemodynamics; sympathetic outflow; vasodilation ADRENOMEDULLIN (AM), a potent 52-amino acid vasodilator, was originally isolated from tissue extracts of human pheochromocytoma (15). AM is a multifunctional peptide that exhibits various actions, such as cardiovascular, renal, and respiratory regulation, as well as central nervous system regulation and regulation of other hormone secretions (2,10,12,16,21,28). AM has also been implicated in various disease states, such as heart failure and renal dysfunction (1,7,9,14,17,18,20). Recently, a new member of the calcitonin generelated peptide (CGRP) family, adrenomedullin 2 (AM2) or intermedin (IMD), was identified (23, 26). Administration of AM2/IMD decreased blood pressure (BP) in mice and rats (23,26), and this effect was partially blocked by AM and CGRP receptor antagonists (23). Takei et al. (26) reported AM2 expression in the kidneys, lungs, gastrointestinal system, thymus, and brain. Most recently, Taylor et al. (27) demonstrated that IMD protein immunoreactivity was present in plasma, as well as in heart, lungs, kidneys, stomach, pituitary gland, and brain. These findings suggest that AM2/IMD is present in various organs of mammals and that AM2/IMD may have physiological effects similar to those of AM and CGRP.Intrarenal infusion of human AM2 decreased BP in a dosedepende...

show abstract

“…Since AM increased blood flow in the isolated adrenal gland in situ and in the intact adrenal gland in vivo, this increased release by hypoxia may play a role in protecting against hypoxia of the adrenal gland. In addition, AM may facilitate the transport of catecholamines and other substances released from the adrenal gland to systemic circulation under hypoxia (36,37).…”

Section: Cells/dish) Were Cultured Under Normoxic (N) (20% O2) or Hypmentioning

confidence: 99%

Pathophysiological Function of Adrenomedullin and Proadrenomedullin N-Terminal Peptides in Adrenal Chromaffin Cells

et al. 2003

View full text Add to dashboard Cite

zyme that methylates noradrenaline into adrenaline.Acetylcholine liberated from splanchnic nerve terminals induces regulated exocytosis of constituents of chromaffin granules in a Ca 2 -dependent manner. The cholinergic receptor subtypes responsible for catecholamine release differ among species; in cows, nicotinic but not muscarinic stimulation induces catecholamine release (2), while in rats and dogs, both nicotinic and muscarinic stimulation induce catecholamine release (3, 4). In addition, the stimulation of cholinergic receptors increases catecholamine synthesis via the activation of TH, the rate limiting enzyme of catecholamine synthesis (5).In addition to catecholamines, chromaffin cells produce a IntroductionAdrenal medullary cells are endocrine cells embryologically derived from the neural crest, which synthesize and release catecholamines. They are composed of adrenaline chromaffin cells and noradrenaline chromaffin cells with minor populations of small intensely fluorescent cells and ganglionic neurons (1). Both adrenaline and noradrenaline chromaffin cells express catecholamine synthesizing enzymes, tyrosine hydroxylase (TH) and dopamine β-hydroxylase (DBH). Adrenaline cells, but not noradrenaline cells, have phenylethanolamine-N methyl transferase (PNMT), an envariety of peptides including chromogranins, opioid peptides and neuropeptide Y (6, 7), which have unique functions such as regulating catecholamine release (8), regulating antibacterial activity (9), sorting peptides from the trans-Golgi network to dense core secretory granules (10), and regulating cell adhesion (11). Catecholamines and other constituents in the chromaffin granules from chromaffin cells are released by pathophysiological stress. Hypoglycemia, hemorrhage, cold exposure or hypoxia causes exocytotic release directly via activation of chromaffin cells, as well as indirectly via activation of the preganglionic sympathetic fibers innervating chromaffin cells (1).On the other hand, adrenomedullin (AM) is a hypotensive peptide that was originally identified in human pheochromocytoma by monitoring of its action on 3 ,5 -cyclic adenosine monophosphate (cAMP) in platelets (12). The AM level in plasma is altered in various diseases; for example, it is increased in patients with hypertension and normalized by anti-hypertensive therapy, indicating that AM is involved in protection against injury occurring in various pathological conditions (13,14). The precursor of AM, the preproAM gene, also produces another hypotensive peptide, the proadrenomedullin N-terminal 20 peptide (PAMP20) (15). However, the mechanisms of action of these peptides are different. In the perfused rat mesenteric arteries, AM directly dilates vascular smooth muscle via receptor that reacts with calcitonin gene-related peptide (CGRP) (16), whereas PAMP20 inhibits noradrenaline release from sympathetic nerve endings, resulting in vasodilatation (17).These peptides are produced not only in pheochromocytoma, but also in almost all organs of the body, and regulate a variety...

show abstract

Effects of a synthetic rat adrenomedullin on regional hemodynamics in rats

Cited by 84 publications

References 14 publications

Regional Hemodynamic Effects of Adrenomedullin in Wistar Rats: A Comparison with Calcitonin Gene-Related Peptide.

Regional Hemodynamic Effects of Adrenomedullin in Wistar Rats: A Comparison with Calcitonin Gene-Related Peptide.

Roles of adrenomedullin 2 in regulating the cardiovascular and sympathetic nervous systems in conscious rats

Pathophysiological Function of Adrenomedullin and Proadrenomedullin N-Terminal Peptides in Adrenal Chromaffin Cells

Contact Info

Product

Resources

About