Age-related respiratory responses to substance P in normal sheep.
The in vivo effects of substance P (SP) on respiratory parameters in four different age groups of sheep were examined. Intravenous SP (10(-8) to 5 x 10(-6) mol kg-1 bodyweight) caused a dose-dependent reduction in dynamic compliance and increase in respiratory resistance in all four groups. The bronchoconstrictor response was age-related, with the greatest response occurring in the youngest age group (four to six months). In the oldest group (over four years) there was minimal bronchomotor response to SP, but a dose-dependent apnoea was present. These findings indicate that there is an age-related alteration in the respiratory response to SP in sheep.
Corcoran
B M
BM
Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Summerhall.
Haigh
A L
AL
D000375:Aging / Q000502:physiology*; D000818:Animals; D005260:Female; D012119:Respiration / Q000187:drug effects*; D012756:Sheep / Q000502:physiology*; D013373:Substance P / Q000494:pharmacology*
D013373:Substance P