RÉSUMÉ
We examined the hypothesis that right handers and left handers may differ in sensory perceptions and respiratory responses to J receptor stimulation with intravenous injections of lobeline HCl in incremental doses. The comparison was made between 6 right handers and 9 left handers (all males) for (i) the dose of lobeline required to produce sensory threshold (viz., first appearance of respiratory sensations) and cough threshold (first appearance of cough); and (ii) latency and duration of sensations for sensory and cough threshold. All these comparisons were not found to be significant statistically. The sensation of breathlessness, and feelings of drowsiness, giddiness and headache were perceived in 3 of the 9 left handers, and in none of the right handers, but the difference was not significant. Reflex bradycardia was recorded only in left handers (5 of 9). The time (sec) for cough threshold was negatively correlated to threshold dose of lobeline (r = -0.5, and P < 0.05). The left handers perceived cough at the threshold as more distressing as compared with right handers (VAS P < 0.05). In conclusion, handedness did not influence J receptor responses to i.v. lobeline.