Vestibular control of intermediate- and long-term cardiovascular responses to experimental orthostasis

Title:

Vestibular control of intermediate- and long-term cardiovascular responses to experimental orthostasis

Creator:

Raffai, G., Csekõ, C., Nádasy, G., and Monos, E.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:feee1968-dbda-4f6f-a540-106cc87cd41f
uuid:feee1968-dbda-4f6f-a540-106cc87cd41f

Subject:

Fyziologie člověka a srovnávací fyziologie, srdeční rytmus, heart rate, arterial blood pressure, cardiovascular control, orthostasis, vestibular lesion, 14, and 612

Type:

article, články, model:article, and TEXT

Format:

print

Description:

Sustained orthostasis elicits the elevation of arterial blood pressure (BP) via sympathetic activation in conscious Wistar rats for at least 2 hours. We tested the hypothesis whether vestibular apparatus plays a role in BP and heart rate (HR) control in response to prolonged gravitational stress. BP and HR responses to 45º head-up for either 2 or 24 hours were monitored by telemetry. Vestibular lesions (VL) were performed by a modified microsurgical-chemical technique. Horizontal BP and HR were not influenced by VL preceding 2-hour tilt. VL abolished the sustained 2-hour BP response to head-up tilt (8.3±0.9 mm Hg relative to horizontal values) while suppressed HR transiently only. VL eliminated diurnal BP fluctuations and decreased HR in horizontal position for 24 hours. Head-up tilt for 24 hours increased BP and HR progressively in intact animals, raising their daily average value by 5.6±0.7 mm Hg and 22.2±6 BPM, respectively. VL resulted in an initial BP rise followed by progressive BP reduction in response to long-term head-up tilt (4±2.2 mm Hg) without eliminating the tachycardia (34.4±5.4 BPM). Thus, blockade of labyrinthine inputs attenuates the BP responses elicited by both intermediate and long-term gravitational stress of orthostatic type. However, other sensory inputs derived from non-vestibular cues (e.g. proprioceptive, visual, visceral, cutaneous etc.) seem to be effective enough to maintain BP normal., G. Raffai ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2010 Volume:59 | Number:1

Harvested from:

CDK

Metadata only:

false