1997 Fiscal Year Final Research Report Summary
Central control mechanisms of calcium homeostasis and its physiological significance
| Project/Area Number |
08458270
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
神経・脳内生理学
|
|---|
| Research Institution | KYUSHU UNIVERSITY |
|---|
Principal Investigator |
AOU Shuji Kyushu University, Dept.of Physiology, Associate Professor, 医学部, 助教授 (40150908)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
TAKE Sachiko Kyushu University, Dept.of Physiology, Research Associate, 医学部, 助手 (80253425)
TAKAKI Atsushi Kyushu University, Dept.of Physiology, Research Associate, 医学部, 助手 (30243934)
HORI Tetsuro Kyushu University, Dept.of Physiology, Professor, 医学部, 教授 (00022814)
|
|---|
| Project Period (FY) |
1996 – 1997
|
| Keywords | lateral hypothalamic area / paraventricular nucleus / ventromedial nucleus / calcium metabolism / bicuculline / hypocalcemia / stomach / parathyroid gland |
|---|
| Research Abstract |
Microinjection of the gamma-aminobutyric acid A receptor antagonist bicuculline methidide into the lateral hypothalamic area decreased the blood concentration of ionized calcium. This hypocalcemic effect was eliminated by a bilateral vagotomy of the gastric branches but not by the coeliac branches or hepatic branches. An intravenous injection of atropine methyl bromide (a muscarinic antagonist), nodrol (a beta-adrenergic blocker), or ranitidine (a histamine H2 blocker) suppressed the bicuculline-induced hypocalcemia. Phenoxybenzamine (a alpha-adrenergic blocker) was ineffective. Secretin or somatostatine (gastrin-release inhibitors) was ineffective either. These results suggest that the hypocalcemia observed after the excitation of lateral hypothalamic neurons was mediated by muscarinic, beta-adrenergic, and histamine H2 receptors through gastric vagus.
Microinjection of bicuculline methidide into the paraventricular hypothamaic nucleus decreased the blood concentration of ionized calcium. This hypocalcemic effect was eliminated by a bilateral vagotomy of the inferior laryngeal nerves or the superior laryngeal nerves which innervated the thyroid and parathyroid glands. An intravenous injection of atropine also suppressed the bicuculline-induced hypocalcemia.
Microinjection of bicuculline methidide into the lateral hypothalamic area also induced hypokalemia which was blocked by nadrol and ranitidine.
These findings strongly suggest that the hypothalamus play an important role in homeostatic control of not only glucose metabolism and visceral functions but also electrolytes such as calcium and potassium.
|
Research Products
(32 results)
