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41.
The gross behavior induced by centrally administered bombesin in rats was compared to that elicited by ACTH-(1–24) and the somatostatin analog, des AA1,2,4,5,12,13[D-Trp8]-somatostatin (ODT8-SS). Bombesin (0.001–1 μg, ICV) caused dose-related excessive scratching which was qualitatively different from that associated with the other two groom-inducing agents. Bombesin-induced grooming was not markedly affected by behaviorally nondepressant doses of haloperidol, morphine, naloxone or neurotensin. Bombesin was active in genetically hypotrichotic (essentially furless) rats; and, again in such animals, even after numbing the area caudal to the shoulders with lidocaine. Tolerance and cross-tolerance studies with bombesin and ODT8-SS indicated that they produce scratching through different mechanisms. Bombesin caused scratching when injected directly into the periaqueductal gray, but not when administered intravenously. Neither hypophysectomy nor adrenalectomy markedly affected bombesin-induced grooming. This behavior appears to be initiated in the central nervous system and is produced independently of the pituitary-adrenal axis. 相似文献
42.
Hypophysectomy was found to have no effect on the concentration of carbonic anhydrase III (CAIII) in male rat liver, whereas in the female, CAIII was elevated 10-fold, to male levels. 相似文献
43.
Prof. Andrey L. Polenov Michael A. Belenky Nadezhda Bogdanović-Stošić 《Cell and tissue research》1981,218(3):607-622
Summary The median eminence (ME) of hypophysectomized rats was studied by means of light and electron microscopy. Paraldehyde-fuchsin (PAF)-positive material is seen in the external zone (EZ) of the ME 2–5 days after the operation. Its amount gradually increases especially in the caudal part of the ME during the following few days. Some PAF-positive fibers make contact with the subependymally located blood capillaries. In the most caudal region of the recessus infundibuli they penetrate into the third ventricle. PAF-positive material decreases markedly from the ME of rats two months after hypophysectomy and exposure to a 1% salt load. Fibers of types A1, A2 and B containing granules of 120–220 nm, 100–150 nm and 80–100 nm in diameter, respectively, are seen in the EZ of the ME in hypophysectomized rats, although almost exclusively A2- and B-type structures make contact with the primary portal capillaries in intact animals. All types of neurosecretory fibers establish contact with the subependymal nonfenestrated blood capillaries and penetrate the recessus infundibuli. Some neurosecretory terminals of different types make direct contact with the glandular cells of the pars tuberalis or are separated from them by a thin basal lamina. It is assumed that mainly neurosecretory fibers of types A2 and B are permanently connected with the primary portal capillaries in the EZ of the ME in intact mammals, while the overwhelming majority of fibers of A1-type shows ingrowth during the course of postoperative reparation. The possible physiological significance of the described changes is discussed. 相似文献