Alteration of vascular response to norepinephrine, calcitonin gene-related peptide, and acetylcholine in orchidectomized rats.
OBJECTIVE
To determine the long-term effects of orchidectomy on vasoreactivity.


METHODS
Orchidectomized rats with or without hormone replacement were raised 1, 2, and 4 months. Vascular responses to norepinephrine, calcitonin gene-related peptide (CGRP), and acetylcholine were tested on three different arteries (thoracic aorta, pulmonary artery, and caudal artery) by functional experiments.


RESULTS
Responses to norepinephrine, CGRP, and acetylcholine were not changed by 1 or 2 months deprivation of androgen. In aorta, the dose-response curve of CGRP was shifted to the left by 1 month of testosterone replacement. Response to norepinephrine was increased 4 months after orchidectomy and reversed by testosterone replacement in thoracic aorta. Orchidectomy did not affect CGRP- and acetylcholine-induced relaxation in all the arteries 4 months after orchidectomy.


CONCLUSIONS
Compared to estrogen, the protective effects of androgen on vasoresponsiveness may be through inhibiting vasoconstriction, but is relatively weak.
Wang
Wang
W
Institute of Vascular Medicine, Third Hospital, Peking University, Bejing, China.
Sun
Chao
C
Wang
Xian
X
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology*; D009919:Orchiectomy; D011651:Pulmonary Artery / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology
D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D013739:Testosterone; D015740:Calcitonin Gene-Related Peptide; D000109:Acetylcholine; D009638:Norepinephrine