[Exposure to ammonium persulphate by inhalation: effect on the NANC inhibitory neurotransmitters in the guinea pig trachea].
To evaluate the effect of ammonium persulphate (AP) inhalation on NANC inhibitory (i-NANC) neurotransmitters of guinea pig airways, we exposed eight guinea pigs to AP (1 mg/m3), by aerosol inhalation for 30 minutes daily for three weeks. Control animals inhaled saline aerosol. After the last exposure, the isolated trachea was mounted in an organ bath and electrically stimulated in the presence of hyoscine, piperoxane and propranolol. The i-NANC responses were evaluated as decreases in intraluminal pressure and expressed as area under the curve (AUC, Pa x seconds). The isolated tracheae were treated with a-chymotrypsin, L-NAME, zinc protoporphyrin IX and ODQ, that inhibit the production or action of the single neurotransmitters, like peptides, NO and CO. In the exposed individuals, the NANC relaxations were below 50%, as compared to controls (P < 0.01). NO and CO were the neurotransmitters responsible for all the i-NANC responses, in similar proportions either in exposed individuals or in controls. In conclusion, ammonium persulphate exposure impairs the i-NANC control of airway tone without specifically affecting any neurotransmitter.
Dellabianca
A
A
Università degli Studi di Pavia, Dipartimento di Medicina Preventiva, Occupazionale e di Comunità. antonio.dellabianca@unipv.it
Tonini
S
S
Faniglione
M
M
De Amici
E
E
De Angelis
S
S
Balestra
B
B
Candura
S M
SM
D000645:Ammonium Sulfate / Q000008:administration & dosage / Q000009:adverse effects*; D000818:Animals; D066298:In Vitro Techniques; D001239:Inhalation; D008297:Male; D050479:Neurotransmitter Transport Proteins / Q000187:drug effects*; D013552:Swine; D014132:Trachea / Q000187:drug effects*
D050479:Neurotransmitter Transport Proteins; C031276:ammonium peroxydisulfate; D000645:Ammonium Sulfate