Passive smoke effects on cough and airways in young guinea pigs: role of brainstem substance P.

Children raised with extended exposure to environmental tobacco smoke (ETS) experience increased cough and wheeze. This study was designed to determine whether extended ETS exposure enhances citric acid-induced cough and bronchoconstriction in young guinea pigs via a neurokinin-1 (NK-1) receptor mechanism at the first central synapse of lung afferent neurons, the nucleus tractus solitarius. Guinea pigs were exposed to ETS from 1 to 6 weeks of age.

Postexercise hypotension in conscious SHR is attenuated by blockade of substance P receptors in NTS.

In hypertensive subjects, a single bout of dynamic exercise results in an immediate lowering of blood pressure back toward normal. This postexercise hypotension (PEH) also occurs in the spontaneously hypertensive rat (SHR). In both humans and SHRs, PEH features a decrease in sympathetic nerve discharge, suggesting the involvement of central nervous system pathways.