Urinary Excretion of Calcitonin Gene-related Peptide in Males with Hot Flushes after Castration for Carcinoma of the Prostate

Abstract

Objective: The majority of men who undergo surgical or medical castration due to prostatic carcinoma develop vasomotor symptoms with hot flushes. The mechanisms behind these symptoms are poorly understood. One possible explanation is a release of the vasodilatory peptide calcitonin gene-related peptide (CGRP) from perivascular nerves, which seem to be involved in the mechanisms behind vasomotion and sweating in postmenopausal women. The aim of this report was to investigate whether CGRP is involved in vasomotion in men after castration therapy. Material and methods: Twenty-four hour urine excretion of CGRP was analysed in 15 men with prostatic carcinoma, using radioimmunoassay before and 3 months after surgical or medical castration. Results: Eleven of the 15 men developed hot flushes during the observation period of 3 months. Twenty-four hour urine excretion of CGRP did not change significantly after castration, either in the group as a whole or in those 11 men who developed hot flushes. Conclusions: Even though we did not observe any significant changes in 24-h urine excretion of the potent vasodilator CGRP after castration it is possible that serum levels of CGRP increase during hot flushes, without having an effect on the 24-h urine excretion of the peptide.