tokens: During the first test 0 . 9 % NaCl was given i . v . ; during the second test 200 micrograms of hCRH ( n = 12 ) or 400 micrograms of TRH ( n = 6 ) was administered i . v . Nine subjects received 0 . 9 % NaCl i . v . during both rebreathing manoeuvres .