TY - JOUR
T1 - The effect of centrally administered adenosine on fetal breathing movements
AU - Bissonnette, John M.
AU - Roger Hohimer, A.
AU - Knopp, Sharon J.
N1 - Funding Information:
Acknowledgements. The authors thank Ms G. WiUeke for technical :~,si~tance and Ms K. Stepper for preparation of the manuscript. This study was supported by National h~stitu~,¢so f Health Grants HL 38039 and HD 10034. No reprints are available.
PY - 1991/5
Y1 - 1991/5
N2 - The central effects of the adenosine analogue l-2-N6-(phenylisopropyl) adenosine (l-PIA) on breathing movements was determined by making injections into the fourth ventricle in unanesthetized fetal sheep. Administration of 0.5 μg l-PIA reduced the percent time during which fetal breathing occurred from 48.0 ± 5.2 (SEM) to 19.5 ± 6.1. Inspiratory slope was reduced to 62 ± 5.5 and 43 ± 5.7 percent of the control values when 0.2 and 0.5 μg l-PIA were given respectively. The effects of l-PIA on the percent time fetal breathing movements occurred and on inspiratory slope were prevented by the prior systemic administration of theophylline (plasma concentrations ∼15 μg/ml). When the vehicle for l-PIA, dimethyl sulfoxide in Ringer solution was given into the fourth ventricle or when 0.5 μg l-PIA was given systemically, there was no effect on fetal breathing. None of these protocols resulted in a change in sagittal sinus blood pH, PO2 or, PCO2. These data indicate adenosine acts at the brain stem to depress fetal respiratory drive.
AB - The central effects of the adenosine analogue l-2-N6-(phenylisopropyl) adenosine (l-PIA) on breathing movements was determined by making injections into the fourth ventricle in unanesthetized fetal sheep. Administration of 0.5 μg l-PIA reduced the percent time during which fetal breathing occurred from 48.0 ± 5.2 (SEM) to 19.5 ± 6.1. Inspiratory slope was reduced to 62 ± 5.5 and 43 ± 5.7 percent of the control values when 0.2 and 0.5 μg l-PIA were given respectively. The effects of l-PIA on the percent time fetal breathing movements occurred and on inspiratory slope were prevented by the prior systemic administration of theophylline (plasma concentrations ∼15 μg/ml). When the vehicle for l-PIA, dimethyl sulfoxide in Ringer solution was given into the fourth ventricle or when 0.5 μg l-PIA was given systemically, there was no effect on fetal breathing. None of these protocols resulted in a change in sagittal sinus blood pH, PO2 or, PCO2. These data indicate adenosine acts at the brain stem to depress fetal respiratory drive.
KW - Adenosine, and fetal breathing
KW - Control of breathing, central mediators
KW - Fetal breathing, effect of adenosine
KW - Theophylline, and fetal breathing
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U2 - 10.1016/0034-5687(91)90123-Z
DO - 10.1016/0034-5687(91)90123-Z
M3 - Article
C2 - 1876764
AN - SCOPUS:0025806282
SN - 1569-9048
VL - 84
SP - 273
EP - 285
JO - Respiratory Physiology and Neurobiology
JF - Respiratory Physiology and Neurobiology
IS - 2
ER -