Short-term effects of octreotide on blood pressure and plasma catecholamines and neuropeptide Y levels in patients with phaeochromocytoma: a placebo-controlled trial.
OBJECTIVE
The observation that phaeochromocytoma possess specific somatostatin binding sites led us to test the hypothesis that octreotide may have antisecretory potential in patients with phaeochromocytoma. We therefore compared the effects of octreotide and placebo on blood pressure and plasma catecholamines and neuropeptide Y.


METHODS
Ten consecutive patients referred to a tertiary care centre for the diagnosis and treatment of a phaeochromocytoma.


METHODS
We performed a crossover comparison of either three 100 micrograms subcutaneous injections of octreotide over one day or 3 injections of octreotide vehicle over another. Blood pressure was measured over 24 hours on each test day using an automatic ambulatory recorder. Blood samples were collected before (at 0800 and 0900 h) and after (at 1000, 1100, 1200, 1300 and 1500 h) placebo or octreotide injection. Plasma catecholamines were assayed by high-performance liquid chromatography and neuropeptide Y was determined using a two-site amplified enzyme immunoassay. All patients then underwent surgery and tumoral somatostatin binding site density was determined by quantitative autoradiography.


RESULTS
Compared to placebo, octreotide did not alter mean 24-hour ambulatory blood pressure or plasma neuropeptide Y, or plasma or urinary catecholamine, levels. Although a moderate reduction in plasma noradrenaline was found in the two patients with the highest tumoral somatostatin binding site densities, overall octreotide-induced variations in plasma noradrenaline did not correlate with somatostatin binding site density. Blood glucose increased from 5.4 +/- 0.3 on placebo to 7.8 +/- 0.5 mmol/l on octreotide (P < 0.01).


CONCLUSIONS
In the present controlled conditions, short-term administration of octreotide had no antisecretory effect in patients with phaeochromocytoma.
Plouin
P F
PF
Department of Hypertension, Hôpital Broussais, Paris, France.
Bertherat
J
J
Chatellier
G
G
Billaud
E
E
Azizi
M
M
Grouzmann
E
E
Epelbaum
J
J
D000310:Adrenal Gland Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D018660:Blood Pressure Monitoring, Ambulatory; D002395:Catecholamines / Q000097:blood*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009478:Neuropeptide Y / Q000097:blood*; D015282:Octreotide / Q000627:therapeutic use*; D010673:Pheochromocytoma / Q000188:drug therapy* / Q000378:metabolism; D017481:Receptors, Somatostatin / Q000378:metabolism; D016037:Single-Blind Method
D002395:Catecholamines; D009478:Neuropeptide Y; D017481:Receptors, Somatostatin; D015282:Octreotide