title: Masked function of amino acid sensors on pancreatic hormone secretion in ventromedial hypothalamic (VMH) lesioned rats with marked hyperinsulinemia.
abstract: In neural regulation of the endocrine pancreas, there is much evidence to suggest that vagal efferents alter insulin and glucagon secretion, but less information on the effects of vagal afferents. In this study, we investigated the role and function of afferent fibers of the vagus nerve in normal and ventromedial hypothalamic (VMH) lesioned rats with marked hyperinsulinemia. In normal rats, hepatic vagotomy was associated with intraperitoneal (ip) arginine-induced enhancement of insulin and glucagon secretion without an accompanying change in blood glucose levels, ip leucine induced enhancement of insulin secretion accompanied by a decrease in blood glucose levels, and ip alanine-induced enhancement of glucagon secretion accompanied by an increase in blood glucose levels. In VMH lesioned rats with marked hyperinsulinemia, none of these amino acids caused significant changes in insulin and glucagon secretion. We conclude that amino acid sensors in normal rats inhibit excess release of pancreatic hormones induced directly by intake of amino acids, such as that in excess protein ingestion, and maintain blood glucose levels within the normal range. In contrast, in VMH lesioned rats with marked hyperinsulinemia, the function of the amino acid sensors is masked due to the marked hyperinsulinemia in these rats.:
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Noriko
authors: N
authors: Ishizuka
authors: Yokohama City University Medical Center, 4-57 Urafunecho, Minami-ku, Yokohama-shi Kanagawa 232-0024, Japan.
authors: Katsuaki
authors: K
authors: Tanaka
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Yoko
authors: Y
authors: Suzuki
authors: Faculty of Dairy Science, Rakuno Gakuen University, 582 Midorimachi, Bunkyodai, Ebetsu-shi, Hokkaido 069-8501, Japan.
authors: Yuri
authors: Y
authors: Kintaka
authors: Faculty of Home Economics, Kyoritsu Women's University, 2-2-1 Hitotsubashi, Chiyoda-ku, Tokyo 101-8433, Japan.
authors: Ikiko
authors: I
authors: Kinoshita
authors: Faculty of Science & Engineering, Teikyo University of Science & Technology, 2-2-1 Senjusakuragi, Adachi-ku, Tokyo 120-0045, Japan.
authors: Takeo
authors: T
authors: Hashiguchi
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Hiroyuki
authors: H
authors: Shimizu
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan. Electronic address:ishuji@kiryu-u.ac.jp.
authors: Akira
authors: A
authors: Senoo
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Nobuo
authors: N
authors: Imazeki
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Yoko
authors: Y
authors: Kobayashi
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Katsumi
authors: K
authors: Arai
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Ryota
authors: R
authors: Haba
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Tosei
authors: T
authors: Takahashi
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Kahoru
authors: K
authors: Sasaki
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Masako
authors: M
authors: Kako
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Kaori
authors: K
authors: Hayashi
authors: National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8636, Japan.
authors: Toshimasa
authors: T
authors: Osaka
authors: University of Shizuoka, School of Food and Nutritional Sciences, 52-1 Yada Suruga-ku, Shizuoka-shi, Shizuoka 422-8526, Japan.
authors: Yuichi
authors: Y
authors: Suzuki
authors: Faculty of Health Care, Kiryu University, 606-7 Azami, Kasakake-cho, Midori-shi, Gunma 379-2392, Japan.
authors: Shuji
authors: S
authors: Inoue