Influence of developmental nicotine exposure on the ventilatory and metabolic response to hyperthermia

Jonathan Ferng, Ralph F Fregosi

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

To determine whether developmental nicotine exposure (DNE) alters the ventilatory and metabolic response to hyperthermia in neonatal rats (postnatal age 2-4 days), pregnant dams were exposed to nicotine (6 mg kg-1 of nicotine tartrate daily) or saline with an osmotic mini-pump implanted subdermally on day 5 of gestation. Rat pups (a total of 72 controls and 72 DNE pups) were studied under thermoneutral conditions (chamber temperature 33°C) and during moderate thermal stress (37.5°C). In all pups, core temperature was similar to chamber temperature, with no treatment effects. The rates of pulmonary ventilation (V˙I), O2 consumption (V˙O2) and CO2 production (V˙CO2 ) did not change with hyperthermia in either control or DNE pups. However, V˙I was lower in DNE pups at both chamber temperatures, whereas the duration of spontaneous apnoeas was longer in DNE pups than in controls at 33°C. The V˙I/V˙O2ratio increased at 37.5°C in control pups, although it did not change in DNE pups. To simulate severe thermal stress, additional pups were studied at 33°C and 43°C. V˙I increased with heating in control pups but not in DNE pups. As heat stress continued, gasping was evoked in both groups, with no effect of DNE on the gasping pattern. Over a 20 min recovery period at 33°C, V˙I returned to baseline in control pups but remained depressed in DNE pups. In addition to altering baseline V˙I and apnoea duration, DNE is associated with subtle but significant alterations in the ventilatory response to hyperthermia in neonatal rats.

Original languageEnglish (US)
Pages (from-to)5201-5213
Number of pages13
JournalJournal of Physiology
Volume593
Issue number23
DOIs
StatePublished - Dec 1 2015

Fingerprint

Nicotine
Fever
Ventilation
Temperature
Hot Temperature
Apnea
Pulmonary Ventilation
Heating
Pregnancy

ASJC Scopus subject areas

  • Physiology

Cite this

Influence of developmental nicotine exposure on the ventilatory and metabolic response to hyperthermia. / Ferng, Jonathan; Fregosi, Ralph F.

In: Journal of Physiology, Vol. 593, No. 23, 01.12.2015, p. 5201-5213.

Research output: Contribution to journalArticle

@article{23dfb10c9ce945a7b6875ef1f2ea2873,
title = "Influence of developmental nicotine exposure on the ventilatory and metabolic response to hyperthermia",
abstract = "To determine whether developmental nicotine exposure (DNE) alters the ventilatory and metabolic response to hyperthermia in neonatal rats (postnatal age 2-4 days), pregnant dams were exposed to nicotine (6 mg kg-1 of nicotine tartrate daily) or saline with an osmotic mini-pump implanted subdermally on day 5 of gestation. Rat pups (a total of 72 controls and 72 DNE pups) were studied under thermoneutral conditions (chamber temperature 33°C) and during moderate thermal stress (37.5°C). In all pups, core temperature was similar to chamber temperature, with no treatment effects. The rates of pulmonary ventilation (V˙I), O2 consumption (V˙O2) and CO2 production (V˙CO2 ) did not change with hyperthermia in either control or DNE pups. However, V˙I was lower in DNE pups at both chamber temperatures, whereas the duration of spontaneous apnoeas was longer in DNE pups than in controls at 33°C. The V˙I/V˙O2ratio increased at 37.5°C in control pups, although it did not change in DNE pups. To simulate severe thermal stress, additional pups were studied at 33°C and 43°C. V˙I increased with heating in control pups but not in DNE pups. As heat stress continued, gasping was evoked in both groups, with no effect of DNE on the gasping pattern. Over a 20 min recovery period at 33°C, V˙I returned to baseline in control pups but remained depressed in DNE pups. In addition to altering baseline V˙I and apnoea duration, DNE is associated with subtle but significant alterations in the ventilatory response to hyperthermia in neonatal rats.",
author = "Jonathan Ferng and Fregosi, {Ralph F}",
year = "2015",
month = "12",
day = "1",
doi = "10.1113/JP271374",
language = "English (US)",
volume = "593",
pages = "5201--5213",
journal = "Journal of Physiology",
issn = "0022-3751",
publisher = "Wiley-Blackwell",
number = "23",

}

TY - JOUR

T1 - Influence of developmental nicotine exposure on the ventilatory and metabolic response to hyperthermia

AU - Ferng, Jonathan

AU - Fregosi, Ralph F

PY - 2015/12/1

Y1 - 2015/12/1

N2 - To determine whether developmental nicotine exposure (DNE) alters the ventilatory and metabolic response to hyperthermia in neonatal rats (postnatal age 2-4 days), pregnant dams were exposed to nicotine (6 mg kg-1 of nicotine tartrate daily) or saline with an osmotic mini-pump implanted subdermally on day 5 of gestation. Rat pups (a total of 72 controls and 72 DNE pups) were studied under thermoneutral conditions (chamber temperature 33°C) and during moderate thermal stress (37.5°C). In all pups, core temperature was similar to chamber temperature, with no treatment effects. The rates of pulmonary ventilation (V˙I), O2 consumption (V˙O2) and CO2 production (V˙CO2 ) did not change with hyperthermia in either control or DNE pups. However, V˙I was lower in DNE pups at both chamber temperatures, whereas the duration of spontaneous apnoeas was longer in DNE pups than in controls at 33°C. The V˙I/V˙O2ratio increased at 37.5°C in control pups, although it did not change in DNE pups. To simulate severe thermal stress, additional pups were studied at 33°C and 43°C. V˙I increased with heating in control pups but not in DNE pups. As heat stress continued, gasping was evoked in both groups, with no effect of DNE on the gasping pattern. Over a 20 min recovery period at 33°C, V˙I returned to baseline in control pups but remained depressed in DNE pups. In addition to altering baseline V˙I and apnoea duration, DNE is associated with subtle but significant alterations in the ventilatory response to hyperthermia in neonatal rats.

AB - To determine whether developmental nicotine exposure (DNE) alters the ventilatory and metabolic response to hyperthermia in neonatal rats (postnatal age 2-4 days), pregnant dams were exposed to nicotine (6 mg kg-1 of nicotine tartrate daily) or saline with an osmotic mini-pump implanted subdermally on day 5 of gestation. Rat pups (a total of 72 controls and 72 DNE pups) were studied under thermoneutral conditions (chamber temperature 33°C) and during moderate thermal stress (37.5°C). In all pups, core temperature was similar to chamber temperature, with no treatment effects. The rates of pulmonary ventilation (V˙I), O2 consumption (V˙O2) and CO2 production (V˙CO2 ) did not change with hyperthermia in either control or DNE pups. However, V˙I was lower in DNE pups at both chamber temperatures, whereas the duration of spontaneous apnoeas was longer in DNE pups than in controls at 33°C. The V˙I/V˙O2ratio increased at 37.5°C in control pups, although it did not change in DNE pups. To simulate severe thermal stress, additional pups were studied at 33°C and 43°C. V˙I increased with heating in control pups but not in DNE pups. As heat stress continued, gasping was evoked in both groups, with no effect of DNE on the gasping pattern. Over a 20 min recovery period at 33°C, V˙I returned to baseline in control pups but remained depressed in DNE pups. In addition to altering baseline V˙I and apnoea duration, DNE is associated with subtle but significant alterations in the ventilatory response to hyperthermia in neonatal rats.

UR - http://www.scopus.com/inward/record.url?scp=84949294341&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84949294341&partnerID=8YFLogxK

U2 - 10.1113/JP271374

DO - 10.1113/JP271374

M3 - Article

C2 - 26427762

AN - SCOPUS:84949294341

VL - 593

SP - 5201

EP - 5213

JO - Journal of Physiology

JF - Journal of Physiology

SN - 0022-3751

IS - 23

ER -