Role of calcitonin gene-related peptide and capsaicin-sensitive afferents in central thyrotropin-releasing hormone-induced hepatic hyperemia.
The involvement of capsaicin-sensitive afferent neurons and calcitonin gene-related peptide (CGRP) in the central thyrotropin-releasing hormone (TRH)-induced hepatic hyperemia was investigated in urethane anesthetized rats. Both systemic capsaicin pretreatment and intravenous administration of CGRP receptor antagonist, human CGRP-(8-37), completely abolished the stimulatory effect of hepatic blood flow induced by intracisternal injection of TRH analog (RX-77368; p-Glu-His-(3,3'-dimethyl)-Pro-NH2, 100 ng), assessed by the hydrogen gas clearance method. These data demonstrate the involvement of capsaicin-sensitive afferent neurons and CGRP in the central TRH-induced stimulation of hepatic blood flow.
Tamori
K
K
Second Department of Medicine and Surgery, Asahikawa Medical College, Japan.
Yoneda
M
M
Yokohama
S
S
Sato
Y
Y
Nakamura
K
K
Kono
T
T
Makino
I
I
Terano
A
A
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology / Q000502:physiology*; D002211:Capsaicin / Q000494:pharmacology*; D002417:Cattle; D006801:Humans; D006940:Hyperemia / Q000139:chemically induced / Q000503:physiopathology*; D007275:Injections, Intravenous; D008099:Liver / Q000098:blood supply*; D008297:Male; D009475:Neurons, Afferent / Q000502:physiology*; D010446:Peptide Fragments / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012039:Regional Blood Flow / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology*; D013997:Time Factors
D010446:Peptide Fragments; C058636:calcitonin gene-related peptide (8-37); D012710:Serum Albumin, Bovine; D013973:Thyrotropin-Releasing Hormone; D015740:Calcitonin Gene-Related Peptide; D002211:Capsaicin