Mechanisms involved in the water intake-related pressor response in the rat

Tavares, Rodrigo Fiacadori; Peres-Polon, Vera Lúcia; Corrêa, Fernando M.A.

doi:10.1097/00004872-200202000-00020

Cited by 10 publications

(15 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The present findings confirmed an increase in HR and BP during water drinking in humans [2] and other animals such as rats [3,6], goats [4,5], and dogs [7].…”

Section: Discussionsupporting

confidence: 85%

“…In this study, water drinking or gastric infusion of 500 ml of water in 2 min may not have resulted in sufficient intragastric pressure to trigger the responses observed by Rossi et al [9]. The data on gastric infusion revealed no significant effects on BP, HR, and MSNA, in accordance with a previous observation in rats [6]. Gastric factors might not be involved in the water drinking-induced rise in BP, at least in this drinking manner.…”

Section: Discussionsupporting

confidence: 81%

“…An enhanced sympathetic activity during drinking was suggested to play a role in the rise in BP [3,6].…”

Section: Introductionmentioning

confidence: 99%

“…Water drinking causes many physiological changes, including fluctuations in endocrine function, cardiovascular system, and fluid balance during or immediately after drinking [1][2][3][4][5][6][7]. Because these changes occur in the early phase of drinking, the contribution of absorbed water from the gastrointestinal tract may be little, if any, but neural factors such as reflex, as with receptors in the oral, pharyngeal, esophageal, or gastric regions, have been suggested.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Changes in Blood Pressure and Muscle Sympathetic Nerve Activity during Water Drinking in Humans.

Endo

Yamauchi²,

Tsutsui³

et al. 2002

JJP

View full text Add to dashboard Cite

Water drinking is recognized to be an essential behavior for fluid homeostasis and is frequently and necessarily observed in daily life. Water drinking causes many physiological changes, including fluctuations in endocrine function, cardiovascular system, and fluid balance during or immediately after drinking [1][2][3][4][5][6][7]. Because these changes occur in the early phase of drinking, the contribution of absorbed water from the gastrointestinal tract may be little, if any, but neural factors such as reflex, as with receptors in the oral, pharyngeal, esophageal, or gastric regions, have been suggested. Stimulation of the oropharyngeal region with water results in a decreased release of vasopressin and causes hypotonic diuresis in humans [1]. Recently, we have demonstrated that water drinking caused a biphasic change in blood volume; an initial hemoconcentration followed by hemodilution in humans [2]. The initial hemoconcentration was likely to be induced by a transient rise in blood pressure (BP) immediately after the onset of drinking. The rise in BP following water drinking by animals and humans might be attributed to stimuli from the oropharyngeal region, gastric distension, or other stimuli [3,[8][9][10], however, the mechanism responsible for the drinking- Japanese Journal of Physiology, 52, 421-427, 2002 Key words: pressor response, microneurography, water ingestion, gastric distension, human. Abstract:To investigate the possible involvement of the sympathetic nervous system in pressor response during water drinking, muscle sympathetic nerve activity (MSNA), blood pressure (BP), and heart rate (HR) were continuously measured in healthy young volunteers throughout the experiments of a 5-min control, 2 min of drinking 500 ml water, and a 28-min recovery. To avoid the effects of water passing through the oropharyngeal and esophageal regions and/or effects of swallowing, an equal amount of water was directly infused to the stomach through a stomach tube for 2 min. Water drinking caused a transient increase in mean arterial pressure (MAP) and HR immediately after drinking (⌬MAP, 12.6Ϯ2.1 mmHg; ⌬HR, ϩ19.9Ϯ1.7 beats/min at the peak). An abrupt decrease of MSNA was observed directly during water drinking (⌬burst rate, Ϫ6.9Ϯ1.3 bursts/min; ⌬total activity, Ϫ2,606Ϯ 491 U/min), and it increased to the baseline level thereafter. Gastric infusion had little or no effect on MAP, HR, and MSNA. The present study demonstrated that a pressor response during water drinking was associated with the attenuation of MSNA and not generated by gastric infusion of water at the same rate as in this drinking manner. In conclusion, the rapid rise in BP might be caused through stimulations from the oropharyngeal region, swallowing-induced factors, and/or a feedforward mechanism by a central descending signal from the higher brain centers.

show abstract

“…The present findings confirmed an increase in HR and BP during water drinking in humans [2] and other animals such as rats [3,6], goats [4,5], and dogs [7].…”

Section: Discussionsupporting

confidence: 85%

Section: Discussionsupporting

confidence: 81%

“…An enhanced sympathetic activity during drinking was suggested to play a role in the rise in BP [3,6].…”

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Changes in Blood Pressure and Muscle Sympathetic Nerve Activity during Water Drinking in Humans.

Endo

Yamauchi²,

Tsutsui³

et al. 2002

JJP

View full text Add to dashboard Cite

show abstract

“…Hypophysectomy was carried out under tribromoethanol anesthesia according to the procedure described by Zarrow et al (1964). Adrenal demedullation was carried out under tribromoethanol anesthesia as described previously (Tavares et al, 2002). Hypophysectomized or demedullated animals were allowed to recover for 5 days before being implanted surgically with intracerebral guide cannulas.…”

Section: Methodsmentioning

confidence: 99%

Pressor effects of electrical stimulation of medial prefrontal cortex in unanesthetized rats

Tavares

Antunes‐Rodrigues

Corrêa

2004

J of Neuroscience Research

View full text Add to dashboard Cite

The medial prefrontal cortex (MPFC) is involved in central nervous system (CNS)-mediated cardiovascular modulation. We compared the cardiovascular effects of electrical stimulation (EE) of the MPFC in unanesthetized rats to those observed after stimulation of the same area in urethane-anesthetized rats. Electrical stimulation (35, 106, 177, 247, 318, and 389 microA rms/10 sec, 60-Hz sine wave) of the MPFC of urethane-anesthetized rats caused depressor responses of stimulus-related intensity. The cardiovascular response to electrical stimulation of the MPFC in unanesthetized rats was characterized by stimulus-related pressor responses. No significant heart rate changes were observed during the EE period in any case. The pressor response to electrical stimulation (106 microA rms/10 sec, 60-Hz sine wave) of the MPFC was not affected by intravenous pretreatment with the vasopressin antagonist dTyr(CH(2))(5)(Me)AVP (50 microg/kg, intravenously), by hypophysectomy, or by intravenous pretreatment with the angiotensin II antagonist losartan (1 mg/kg, intravenously). The pressor response was blocked by intravenous pretreatment with the ganglionic blocker mecamylamine (2 mg/kg, intravenously) but was not affected by adrenal demedullation, thus suggesting involvement of the neural component of the sympathetic nervous system without a major involvement of its hormonal component. Our results confirmed the occurrence of depressor responses after electrical stimulation of the MPFC in urethane-anesthetized rats and evidenced that only pressor responses are observed after its stimulation in unanesthetized rats. The fact that the pressor response to the stimulation of the MPFC was blocked by a ganglioplegic suggests that the MPFC has functional excitatory actions over the sympathetic nervous system.

show abstract

Cardiovascular effects of noradrenaline microinjection into the medial part of the superior colliculus of unanesthetized rats

Pelosi

Tavares

Fernandes³

et al. 2009

Brain Research

View full text Add to dashboard Cite

Mechanisms involved in the water intake-related pressor response in the rat

Cited by 10 publications

References 27 publications

Changes in Blood Pressure and Muscle Sympathetic Nerve Activity during Water Drinking in Humans.

Changes in Blood Pressure and Muscle Sympathetic Nerve Activity during Water Drinking in Humans.

Pressor effects of electrical stimulation of medial prefrontal cortex in unanesthetized rats

Cardiovascular effects of noradrenaline microinjection into the medial part of the superior colliculus of unanesthetized rats

Contact Info

Product

Resources

About