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The thalamic projections to the hippocampal formation and to the subicular and entorhinal areas in the cat have been studied with retrograde transport of horseradish peroxidase (HRP) or wheat germ agglutinin conjugated to HRP (WGA-HRP) and anterograde transport of WGA-HRP. Retrograde transport tracers injected in various parts of these cortices resulted in labeled cells in the midline, anterior, and lateral dorsal nuclei. Injections into the hippocampal formation or the subiculum led to retrograde labeling of cells in the reuniens nucleus of the ipsilateral thalamus throughout its rostrocaudal extent, whereas the restricted injections into the dentate gyrus and the inferior region of the hippocampus led to no labeling. Following an injection into the pre- and parasubiculum, a large number of labeled cells were seen not only in the reuniens nucleus but in other midline nuclei. In addition, a substantial number of labeled cells were also detected in the anterior and lateral dorsal nuclei, particularly in the anterodorsal nucleus, which contained densely arranged labeled cells throughout almost the entire rostrocaudal extent. An injection into the medial entorhinal area labeled a number of cells in the anterior nuclei and in the reuniens nucleus, particularly its dorsal part. Injections into various subdivisions of the lateral entorhinal area yielded different patterns of distribution of labeled cells in the thalamic nuclei. An injection into the ventromedial division (VMEA) led to abundant labeling of cells in the paraventricular and reuniens nuclei. After an injection into the ventral division (VLEA), numerous labeled cells were detected in the reuniens nucleus and a lesser number in the paraventricular nucleus at anterior levels. When an injection was made into the dorsal division (DLEA), a large number of labeled cells were detected in the reuniens nucleus, and less numerous labeled cells were found in the central medial nucleus. There appears to be a topographic arrangement of cortical projections of the reuniens nucleus. The pre- and parasubiculum receive projections from the most medial part of the reuniens nucleus near the midline, and the DLEA receives projections from the medial part of the nucleus. The cells projecting to the VLEA and MEA are distributed in the central part of the reuniens nucleus, and those to the VMEA are distributed in the lateral part. Anterograde experiments were also performed; injections of WGA-HRP into the reuniens nucleus resulted in terminal labeling in the superficial layers of the subicular area and the neighboring hippocampus and in the entorhinal area.

appetite; vagus; fundus; stomach; medulla GHRELIN IS A RECENTLY IDENTIFIED endogenous ligand for growth hormone secretagogue receptor (GHS-R) and was originally isolated from the stomach (19). In addition to GH-releasing activity, ghrelin has an orexigenic (appetite-enhancing) effect. This is very reasonable, since the blood ghrelin level rose sharply just before onset of the dark phase, and the stomach ghrelin level was high during fasting in rats (30). Ghrelin has been shown to be present not only in the stomach but also in the hypothalamus, and it participates in the regulation of food intake itself and feeding-related phenomena through the peripheral and central nervous system (5, 25). Since feeding is closely related to digestive function, the effects of orexigenic peptides on gastric acid secretion, bile secretion, and gastric motility have been well investigated (3,10,15,18,20,24,29,35). Orexigenic peptides generally stimulate gastric acid secretion (23,24,33) and phasic contractions of the distal stomach (3,15,20,23), which enhance the ability to churn the gastric contents to accelerate gastric emptying; these gastric functions are particularly important for digestion. Accommodation of food is also important for smooth digestion, and impaired accommodation is thought to be one of the factors inducing meal-related symptoms, such as functional dyspepsia (31). The proximal region of the stomach, which serves as a reservoir, relaxes to accommodate food and fluid during swallowing (2, 17). Our previous studies revealed that fourth ventricular administration (and/or intramedullary injections) of orexin-A and neuropeptide Y (NPY), which are well-known orexigenic peptides, induced relaxation of the proximal stomach to facilitate the reservoir function of the stomach (15, 18).Ghrelin, as well as other orexigenic peptides, controls gastric functions. Intravenous administration of ghrelin stimulates gastric acid secretion and gastric motility in rats (23). Central and peripheral administration of ghrelin induced fasted motor activity of the gastrointestinal tract in rats (8). Histological study confirmed GHS-R mRNA expression in several hypothalamic nuclei, many of which have long been recognized as playing roles in body weight and food intake in rats and mice (37). In addition, GHS-R mRNA has also been found in the dorsal vagal complex (DVC), including the area postrema (AP), nucleus of the solitary tract (NST) and dorsal motor nucleus of the vagus (DMV). Immunohistochemical study revealed that GHS-R was expressed in the NST and DMV in rats (22). Microinjection of ghrelin into the DVC facilitated food intake (7). Since the DVC is the center for controlling gastric motility, it is plausible that ghrelin induces relaxation of the proximal stomach, as well as other orexigenic peptides, as shown in our previous studies (15,18). Additionally, recent studies revealed that the intermediate and caudal DMV contain different groups of preganglionic neurons (21, 36). It is well known that the caudal part of the DMV is involv...

Immunohistochemical staining properties of amyloids with anti-keratin antibodies were investigated using an avidin-biotin-peroxidase complex (ABC) system on formalin-fixed, paraffin-embedded sections. Anti-keratin antibody EAB-903 which recognize 66K and 57K daltons keratin peptides reacted with amyloid deposits in both lichen amyloidosus (LA) and macular amyloidosis (MA), but did not react with either primary systemic amyloidosis (AL), secondary systemic amyloidosis (AA) or heredofamilial amyloid polyneuropathy (AF). However, anti-keratin antibodies EAB-904 and MAK-6 did not react with any types of amyloids. These results suggested that immunohistochemical staining with anti-keratin antibody EAB-903 using formalin-fixed, paraffin-embedded sections appeared to be a useful method in making differential diagnosis of primary localized cutaneous amyloidosis (AD).

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