Hormone
Metabolism in the Pulmonary Circulation
G. ALIBERTI1, I. PULIGNANO1, M. PROIETTA1, F. MIRALDI2,
L. CIGOGNETTI2, L. TRITAPEPE2, C. DI
GIOVANNI2, R. ARZILLA2,
E. VECCI1, M. TOSCANO2
1Department
of Clinical Science and 2Institute
"Chirurgia del Cuore e dei Grossi
Vasi", University of Rome "La
Sapienza", Rome, Italy
Received
February 21, 2000
Accepted September 21, 2000
Summary
We
measured hormonal levels in blood samples from
pulmonary and radial arteries in 117 patients
undergoing aorto-coronary by-pass surgery with
the aim of investigating the role of the
pulmonary vessel endothelium in hormone
metabolism. Insulin and glucagon concentrations
were significantly higher in pulmonary artery
blood with respect to radial artery blood (73±65
vs. 65±47 pmol/l, p<0.005, and 80+49 vs.
73+51 ng/l, p<0.01, respectively), while no
difference was found for growth hormone,
prolactin, C peptide, insulin-like growth factor
I, follicle stimulating hormone, luteinizing
hormone, thyroid stimulating hormone, parathyroid
hormone, thyroglobulin, triiodothyronine,
thyroxine, free triiodothyronine, and free
thyroxine. Moreover, prolactin concentrations
were more than twice the normal levels, this
being an effect of propafol and the opiate
fentanyl used for the general anesthesia.
Assuming that the arteriovenous differences
observed are a marker of peptide hormone
degradation, our study has demonstrated that with
similar kinetics insulin and glucagon secreted
into portal circulation and escaping from hepatic
extraction undergo further homeostatic removal of
about 9-10 % in the pulmonary circulation before
entering the general circulation.
Key
words
Peptide
hormones · Thyroid hormones · Endothelial
cleavage · Lung · Insulin · Glucagon ·
Peptide degradation
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Prof.
Giuseppe Aliberti, Dipartimento di Scienze
Cliniche, Policlinico Umberto I, Viale del
Policlinico, 00161 Roma, Italy.
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