Plasma guanosine 3',5'-monophosphate responses to the cold pressor test in patients with vibration disease.
Plasma cyclic guanosine 3',5'-monophosphate (cyclic GMP) levels were determined during the cold pressor test (CPT) in 10 normal volunteers and 39 patients with vibration disease. The CPT caused no significant increase in plasma cyclic GMP in the controls. There was a sharp rise in plasma cyclic GMP during and after the CPT in patients with vibration disease. This increase was suppressed by simultaneous injection of phentolamine or atropine. In patients who had been treated with kallidinogenase or nicametate citrate for 3-6 months, the CPT caused no significant increase in plasma cyclic GMP. In 1 patient the plasma cyclic GMP was suppressed by dihydroergotamine. From these findings it is very likely that cholinergic or alpha-adrenergic receptor responses are enhanced in patients with vibration disease.