Synergism of intraventricular NaCl infusion and subpressor angiotensins in rats

1989 ◽  
Vol 256 (1) ◽  
pp. H1-H8 ◽  
Author(s):  
K. Katahira ◽  
H. Mikami ◽  
T. Ogihara ◽  
K. Kohara ◽  
A. Otsuka ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Intravenous Infusion ◽  
Wistar Rats ◽  
Concomitant Administration ◽  
Base Line ◽  
Ang Ii ◽  
Intracerebroventricular Infusion ◽  
Male Wistar Rats ◽  
The Central Nervous System

The effect of selective salt infusion to the central nervous system on the blood pressure (BP) regulation was examined in male Wistar rats. Hypertonic NaCl (0.8 M, 1 microliter/h) was infused into the lateral ventricle concomitantly with intravenous infusion of a subpressor dose (5.4 pmol.kg-1.min-1) of angiotensin II (ANG II) or its analogues for 7 days using osmotic minipumps. The BP was not increased by intracerebroventricular infusion of NaCl alone at this dose but was significantly and consistently increased by concomitant intravenous infusion of ANG II or its analogues. The increases in the BP over the base-line values on day 7 in groups on infusions of ANG II, ANG III, and pentasarcosyl-ANG II [(Sar)5ANG II] were 29 +/- 5 mmHg (n = 9, P less than 0.05), 8 +/- 2 mmHg (n = 8, P less than 0.05), and 19 +/- 3 mmHg (n = 6, P less than 0.05), respectively. The responses to hexamethonium, prazosin, and antagonists of arginine vasopressin and ANG II were examined in separate sets of conscious and unrestrained animals that had received intracerebroventricular infusion of NaCl and intravenous infusion of ANG II for the preceding 6 days. These animals showed significantly greater depressor responses only to hexamethonium and prazosin than control. These results indicate that the pressor effect of continuous and concomitant administration of intracerebroventricular NaCl and intravenous ANG II is mainly due to activation of the sympathetic nerve function. Synergism of the effects of selective central sodium administration and a subpressor dose of ANG II in the central nervous system is suggested.

RAS in the Central Nervous System: Potential Role in Neuropsychiatric Disorders

2018 ◽  
Vol 25 (28) ◽  
pp. 3333-3352 ◽  
Author(s):  
Natalia Pessoa Rocha ◽  
Ana Cristina Simoes e Silva ◽  
Thiago Ruiz Rodrigues Prestes ◽  
Victor Feracin ◽  
Caroline Amaral Machado ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Central Nervous System ◽  
Nervous System ◽  
Therapeutic Potential ◽  
Neuropsychiatric Disorders ◽  
Extensive Literature ◽  
Ang Ii ◽  
Mas Receptor ◽  
The Central Nervous System ◽  
The Brain

Background: The Renin-Angiotensin System (RAS) is a key regulator of cardiovascular and renal homeostasis, but also plays important roles in mediating physiological functions in the central nervous system (CNS). The effects of the RAS were classically described as mediated by angiotensin (Ang) II via angiotensin type 1 (AT1) receptors. However, another arm of the RAS formed by the angiotensin converting enzyme 2 (ACE2), Ang-(1-7) and the Mas receptor has been a matter of investigation due to its important physiological roles, usually counterbalancing the classical effects exerted by Ang II. Objective: We aim to provide an overview of effects elicited by the RAS, especially Ang-(1-7), in the brain. We also aim to discuss the therapeutic potential for neuropsychiatric disorders for the modulation of RAS. Method: We carried out an extensive literature search in PubMed central. Results: Within the brain, Ang-(1-7) contributes to the regulation of blood pressure by acting at regions that control cardiovascular functions. In contrast with Ang II, Ang-(1-7) improves baroreflex sensitivity and plays an inhibitory role in hypothalamic noradrenergic neurotransmission. Ang-(1-7) not only exerts effects related to blood pressure regulation, but also acts as a neuroprotective component of the RAS, for instance, by reducing cerebral infarct size, inflammation, oxidative stress and neuronal apoptosis. Conclusion: Pre-clinical evidence supports a relevant role for ACE2/Ang-(1-7)/Mas receptor axis in several neuropsychiatric conditions, including stress-related and mood disorders, cerebrovascular ischemic and hemorrhagic lesions and neurodegenerative diseases. However, very few data are available regarding the ACE2/Ang-(1-7)/Mas receptor axis in human CNS.

Intracerebroventricular infusion of RU28318 blocks aldosterone-salt hypertension

1990 ◽  
Vol 258 (3) ◽  
pp. E482-E484 ◽  
Author(s):  
E. P. Gomez-Sanchez ◽  
C. M. Fort ◽  
C. E. Gomez-Sanchez
Keyword(s):  
Blood Pressure ◽  
Central Nervous System ◽  
Nervous System ◽  
Systolic Blood Pressure ◽  
Urine Volume ◽  
Intracerebroventricular Infusion ◽  
Mineralocorticoid Antagonist ◽  
Salt Hypertension ◽  
The Central Nervous System ◽  
Dose Dependent

The chronic intracerebroventricular (icv) infusion of aldosterone in rats and dogs elevates the blood pressure within 10-14 days at doses far below those that produce hypertension systemically. The effect in rats is dose dependent and blocked by the concomitant icv infusion of the antimineralocorticoid, prorenone. The effect of the icv infusion of RU28318, another specific spironolactone mineralocorticoid antagonist, on the hypertension produced by chronic subcutaneous (sc) administration of aldosterone in sensitized rats was reported. Miniosmotic pumps were used to deliver 1 micrograms/h aldosterone sc and 1.1 micrograms/h RU8318 icv. Over a 24-day period the indirect systolic blood pressure of the control, RU28318 icv, and aldosterone sc plus RU28318 icv groups increased from 105 to 123 mmHg and were not significantly different from each other, whereas the aldosterone sc group increased to 156 mmHg. RU28318, icv or sc, did not alter the increase in urine volume produced by aldosterone sc, and there was no significant differences in weight between the groups. This study provides evidence of the importance of the central nervous system in the pathogenesis of hypertension produced by systemic mineralocorticoid excess.

A new pharmacological approach to the diagnosis of hyperprolactinaemic states: the nomifensine test

1980 ◽  
Vol 93 (2) ◽  
pp. 139-148 ◽  
Author(s):  
Andrea R. Genazzani ◽  
Franco Camanni ◽  
Ferdinando Massara ◽  
Enrico Picciolini ◽  
Daniela Cocchi ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Pituitary Adenoma ◽  
Antidepressant Drug ◽  
Sella Turcica ◽  
Pituitary Tumour ◽  
Base Line ◽  
Clear Cut ◽  
The Central Nervous System ◽  
Plasma Prl

Abstract. The prolactin-(Prl) lowering effect of nomifensine (Nom), an antidepressant drug which activates dopamine (DA) neurotransmission mainly by inhibiting DA re-uptake in the central nervous system (CNS), was investigated in normoprolactinaemic subjects, in subjects with physiological puerperal hyperprolactinaemia or pathological hyperprolactinaemia. Nom (200 mg po) administered to 23 normoprolactinaemic women induced a significant decrease in baseline Prl, which was more marked (about 50% inhibition at 120 min) and prompt (30 min) in the subjects who had 'high' Prl levels (>12<20 ng/ml) (13 subjects) than in those with 'low' Prl levels (≤ 12 ng/ml). Also in 9 puerperal women (postpartum day 2) oral administration of 200 mg Nom was followed by a clear-cut decrease of base-line Prl, which started at 30 min and reached nadir values at 150–180 min (about 60% inhibition). Administration of Nom (200 mg po) to 47 subjects with pathological hyperprolactinaemia evidenced the presence of Nom non-responder (36 cases) or responder (11 cases) subjects. In 22 of the Nom non-responder subjects the existence of a Prl-se creting pituitary tumour was established at surgery by selective removal of an adenoma via the transsphenoidal route; of the 14 subjects who did not undergo surgery, 1 had evident and 5 had minor alterations of the sella turcica and, in addition, in 3 subjects the duration of amenorrhoea was longer than 5 years. Only 5 subjects of this group had no radiological alterations of the sella turcica, in presence of basal Prl levels ranging between 50–126 ng/ml. In contrast, 10 out of the 11 Nom-responder subjects had a radiologically normal sella turcica and basal Prl levels lower than 50 ng/ml. Administration of 2-Br-α-ergocriptine (2.5 mg po), a direct stimulant of pituitary DA receptors, to subjects with pathological hyperprolactinaemia (39 cases) induced a striking fall in plasma Prl levels (about 80% inhibition at 240 min), irrespective of the type of Prl responsiveness to Nom. These results indicate that Nom lowers plasma Prl levels in both normoprolactinaemic and hyperprolactinaemic subjects; in the latter, by virtue of its ability to affect selectively DA neurotransmission in the CNS, the drug appears capable of discriminating between individuals with and without pituitary adenoma.

scholarly journals Standarization of a Protocol of Immunohistochemistry for the Detection of Brain Microglia in Wistar Rats

2017 ◽  
Vol 19 (3) ◽  
pp. 45
Author(s):  
Karol Ramírez Chan DDS, MSc, PhD ◽  
Jaime Jaime Fornaguera-Trías PhD
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Immune System ◽  
Wistar Rats ◽  
Secondary Antibody ◽  
Research Activity ◽  
The Central Nervous System ◽  
Near Future ◽  
The Brain ◽  
Microglia Morphology

Objective: Standardize a protocol of immunohistochemistry that has been widely used in C57BL/6J mice to identify microglia of the central nervous system in Wistar rats.  Materials and Methods: This research activity was carried out in two parts. In the first part, a protocol of immunohistochemistry was implemented to identify microglia in the central nervous system of 6 Wistar rats. A primary antibody with reactivity to rat and a specific secondary antibody to the primary were used. Once the protocol was established in rats' brains, an immunological challenge was produced with the intraperitoneal application of lipopolysaccharide in 2 Wistar rats, in order to evidence the changes in microglia morphology.  Results and Discussion: We demonstrate that without making major modifications to the original protocol, it can also be used to identify microglia in adult Wistar rats. In the near future, this immunostaining protocol will be applied to elucidate the bidirectional interaction between the brain and the immune system, under homeostatic conditions and different physiological and pathological stimuli.

scholarly journals Both Nox2‐ and Nox4‐containing NAD(P)H oxidases are required for the full vasopressor effects of angiotensin‐II (Ang‐II) in the central nervous system

2007 ◽  
Vol 21 (6) ◽  
Author(s):  
Jeffrey Peterson ◽  
Melissa A. Burmeister ◽  
Xin Tian ◽  
John A. Stupinski ◽  
Ram V. Sharma ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Angiotensin Ii ◽  
Ang Ii ◽  
The Central Nervous System

Intravenous infusion of iduronidase-IgG and its impact on the central nervous system in children with Hurler syndrome

2017 ◽  
Vol 120 (1-2) ◽  
pp. S55-S56 ◽  
Author(s):  
Roberto Giugliani ◽  
Igor Nestrasil ◽  
Steven Chen ◽  
William Pardridge ◽  
Patrice Rioux
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Intravenous Infusion ◽  
Hurler Syndrome ◽  
The Central Nervous System

scholarly journals Estudo farmacológico do Heterothalamus brunioides: dose letal, atividade geral e sistema nervoso central

1987 ◽  
Vol 9 (9) ◽  
pp. 77
Author(s):  
Adriana Pizzutti dos Santos ◽  
Juliane Lavarda ◽  
Claúdio Sityá ◽  
Paulo Ricardo Führ ◽  
Ana Maria Chagas
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Wistar Rats ◽  
General Activity ◽  
Toxicological Effect ◽  
Popular Medicine ◽  
Snake Bites ◽  
The Central Nervous System

Heterothalamus brunioides Less is a native herb in Santaninha da Boa Vista (RS), and it is used in popular medicine to decrease toxilogical effect caused by snake bites. The objective of this study was to evaluate the lethal dosis as well as the effects of the aquous extract of this plant upon the general activity and central nervous system. The lethal dosis on Wistar rats was 143,2 mg/kg of the cold aquous extract and when it was boiled none toxicological effect was observed. So, this substance is thermolabile. Since the general activity was not effects by the use of this drug, there is no non-indication for its recomendation. The effect upon the central nervous system is characterized by depression.

Myelin composition in the central nervous system of mutant Han-Wistar rats

1978 ◽  
Vol 9 (2-3) ◽  
pp. 201-205 ◽  
Author(s):  
G.E. Fagc ◽  
V. Neuhoff ◽  
K.-H. Sontag ◽  
N.N. Osborne
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Wistar Rats ◽  
The Central Nervous System

The incidence of spontaneous tumors of the central nervous system of wistar rats

1976 ◽  
Vol 35 (1) ◽  
pp. 1-13 ◽  
Author(s):  
N. Sumi ◽  
D. Stavrou ◽  
H. Frohberg ◽  
G. Jochmann
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Wistar Rats ◽  
Spontaneous Tumors ◽  
The Central Nervous System

Systemic angiotensin acts at subfornical organ to facilitate activity of neurohypophysial neurons

1986 ◽  
Vol 251 (4) ◽  
pp. R712-R717 ◽  
Author(s):  
A. V. Ferguson ◽  
L. P. Renaud
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Electrical Stimulation ◽  
Subfornical Organ ◽  
System Structure ◽  
Ang Ii ◽  
Cell Excitability ◽  
Long Duration ◽  
The Central Nervous System ◽  
Synaptic Changes

Extracellular single unit recordings were obtained to investigate the effects of systemic administration of angiotensin II (ANG II) on the excitability of antidromically identified neurohypophysial neurons in the rat. Records were obtained from 89 oxytocin- or vasopressin-secreting neurons in the hypothalamic supraoptic or paraventricular nuclei. Increased excitability in response to ANG II was observed in 83% of putative vasopressin- and 75% of putative oxytocin-secreting neurons tested in intact animals. Lesion studies to identify the central nervous system site of action for such peripherally administered ANG II showed that, after electrolytic lesion of the rostral subfornical organ (SFO), neurohypophysial neurons demonstrated no increase in excitability in response to this peptide. In an attempt to correlate the synaptic events through which activation of SFO neurons may result in facilitated excitability of neurohypophysial cells, 19 cells were tested with both systemic ANG II and electrical stimulation in the SFO. These studies demonstrated that all cells which showed long-duration increases in excitability in response to electrical stimulation of SFO were also activated by systemic ANG II. It is concluded that the SFO is an essential central nervous system structure in eliciting increases in the excitability of both oxytocin- and vasopressin-secreting neurons in response to systemic ANG II. These effects may involve the activation of SFO efferents that evoke long-duration post-synaptic changes in neurohypophysial cell excitability.

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