Effect of cold-restraint stress on immunoreactive thyrotropin-releasing hormone and immunoreactive somatostatin in the rat stomach.
The effects of cold-restraint stress on immunoreactive thyrotropin-releasing hormone (ir-TRH) and immunoreactive somatostatin (ir-SOM) concentrations in the rat stomach were investigated. Rats immobilized with a spring-loaded metallic plate were placed in a room maintained at 4 degrees C for 1-3 h and then decapitated serially for investigation. Gastric ir-TRH and ir-SOM concentrations were measured by individual radioimmunoassays. Cold-restraint stress induced gastric mucosal lesions as well as a decrease of the ir-TRH concentration in the glandular stomach, an increase of the ir-TRH concentration in the gastric juice, and a decrease in gastric pH. In contrast, this stress caused an increase of ir-SOM in the glandular stomach and a decrease of ir-SOM in the gastric juice. However, cold or restraint stress alone did not induce gastric mucosal lesions or changes in gastric ir-TRH and ir-SOM concentrations or the gastric pH. To clarify the endocrine influence of peripheral TRH, pretreatment with thyroid hormone was performed to inhibit elevation of the serum TRH level during cold-restraint stress. Despite this pretreatment, cold-restraint stress still induced ulcer formation, along with changes in gastric ir-TRH and ir-SOM concentrations and gastric pH. These findings suggest that changes in gastric ir-TRH and ir-SOM concentrations may be closely related to ulcer formation due to cold-restraint, and that TRH may act in a paracrine manner in the stomach.
Nagai
H
H
Fourth Department of Internal Medicine, Aichi Medical University, Japan.
Morise
K
K
Mitsuma
T
T
Furusawa
A
A
Kaneko
H
H
Uchida
K
K
Yamamoto
H
H
D000818:Animals; D003080:Cold Temperature; D005750:Gastric Juice / Q000187:drug effects / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008297:Male; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D012007:Rectum; D013004:Somatostatin / Q000097:blood / Q000378:metabolism*; D013270:Stomach / Q000187:drug effects / Q000503:physiopathology; D013312:Stress, Physiological / Q000378:metabolism*; D013696:Temperature; D013963:Thyroid Hormones / Q000494:pharmacology; D013973:Thyrotropin-Releasing Hormone / Q000097:blood / Q000378:metabolism*
D013963:Thyroid Hormones; D013004:Somatostatin; D013973:Thyrotropin-Releasing Hormone