Effects of cotton bract extract (CBE) on airway smooth muscle and nerves.
Fedan-JS; Franczak-MS; Cahill-JF; Kosten-CJ; Morey-P
Proceedings of the Seventh Cotton Dust Research Conference, beltwide cotton production research conferences, January 3-4, 1983, San Antonio, Texas. Wakelyn PJ, Jacobs RR, eds. Memphis, TN: The National Cotton Council of America, 1983 Jan; :4 pages
The effect of a crude aqueous extract of cotton bract (CB) was investigated on isolated trachealis muscle of dogs and guinea-pigs. Bracts, typical of those incorporated into harvested cotton were collected, ground to powder, and extracted in non pyrogenic water. The filtrate was lyophilized to dryness and the resulting powder reconstituted in sterile non pyrogenic saline. Animals were anesthetized and tracheas removed. Single or paired tracheal segments were prepared, mounted in water jacketed organ chambers and equilibrated under resting tension for one hour. Test drugs included phentolamine (50602), propranolol (525666), guanethidine (55652), and atropine (51558). Doses used ranged from 0.0001 to The neurogenic responses of tissues to electrical field stimulation were measured at 7 minute intervals. CB produced contraction of both tissues. Cumulative additions of CB in dogs lead to progressively greater contractile response. CB produced responses at lesser concentrations in guinea-pigs and at higher concentrations induced relaxation of the tissues. CB did not provoke 5-HT like activity in the trachealis of either species. CB potentiated the stimulation induced contractions of dog trachealis but not of guinea- pig tissue. The CB potentiated stimulation, produced a relaxing effect on the guinea-pig trachealis but had little or no effect on the responses of the dog tissues. In the presence of phentolamine, propranolol, and guanethidine the neurogenic contraction responses of the trachealis were reduced significantly to CB in guinea-pigs. The opposite response was observed in dogs. In the presence of atropine, CB produced a significant potentiation of stimulation induced relaxation response in guinea-pig trachealis. Methysergide did not in any 5-HT like response in the dog or guinea-pig. The authors conclude that a species difference exists in response to CB effects on airways smooth muscle and on neurotransmission to the muscle which could influence the normal control of its tone.
Cotton-dust; Animal-studies; Biological-effects; Neuromuscular-system; Electrical-stimulation; Electrophysiological-measurements; Muscle-contraction; Neurophysiology; Nerve-fiber-excitation;
50-60-2; 525-66-6; 55-65-2; 51-55-8;
Proceedings of the Seventh Cotton Dust Research Conference, beltwide cotton production research conferences, January 3-4, 1983, San Antonio, Texas